text:
Creality 3D Ender-4, a "extruder kit" does not fit the frame
This is my first time building a 3D printer (a "Creality Ender-4").
Everything is going fine except the "extruder kit" part that does not have enough space to attach on the frame.  Should I drill it to have a longer hole so it can be attached to the frame? I just want another set of eyes to look at it to make sure I'm not crazy.

It looks like the body of the stepper motor may not be quite square. Would you be able to install it rotated 90 degrees and get the clearance you need?

I submitted an edit that fixes the images

Try loosening all the screws that hold the motor/filament feeder to the bracket.  There may be enough slop to skooch it over a bit and get it to fit.

Dude, you're absolutely not crazy, I almost put the entire thing back in the box when I realized I'd have to void the warranty just to finish putting together my printer but I wound up boring out the holes a bit closer to the edges of the extruder and assembling it all the same, it works wonderfully now that I have it attached.

Yep, I ended up drilling the holes, and I've been printing successfully since then.

From the photo on their website, it looks like you are orienting it correctly.
Here is a photo to confirm the orientation.

Note: I added this as an answer so I could share the photo

Your request appears to be "another set of eyes" and I'll add to that by adding another photo:

If you compare the photo from the official store you can see the gap between the mounting screw and the body of the extruder assembly is obviously wider in the official photo. On the plus side, the extruder mount is not something that would be considered system critical, because you're using a Bowden tube design. Even a bit of misalignment would mean zero impact on the printed model quality.
Consider to contact the seller, including the photo from the store and your photo and ask for a correct mounting plate. You would likely be able to use the oversize hole mount until a replacement arrives. For such a small part, they should not charge you.

From this photo, it appears that the plate has slotted holes for the motor and extruder, and it looks like it is installed further to the right than on @koko's photos. Perhaps the position of the motor can be adjusted to make room?


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Which choices do we have on Daylight Resins?
I'm planning to make an LCD Resin printer. I'm still learning and I found out that I need daylight resin (which hardens when white light comes from the LCD).
If I search for "Daylight resin" on Google, the only "useful" result I find is for Photocentric.

Photocentric sells Daylight resins and the prices seem to be good too; however, I'm trying to search for alternatives. I'm not interested in something cheaper, I'd like to choose a resin which has more colors. Photocentric's hard resin only comes in cream/green/gray colors. I would need at least white/black/transparent resin.
Is it the only option we have?  Are there any other manufacturer out there which produces Daylight resin/LCD-hardening resin with a variety of colors?

Take a look into this forum: http://www.buildyourownsla.com/forum/viewforum.php?f=13

It looks like Ono may fit what you are looking for.
They have several colors listed on their site.
Red     Blue
Yellow   Black
Clear  Creamy White
They also have a flexible resin and a low temperature "casting" resin.
It is unclear if the resin is available now or if it is preorder.

It is on preorder. that would be a good alternative, do you know if it's the only option we have? Also, "Clear" is not that clear... It's more like translucent yellow. This is clear to me

@BackSlash I think the observation that the "whitest" and "clearest" resins they make have a yellow tint indicates their base resin has a yellow tint.  Looking more carefully at the "red" and "blue" I can see it there are well as the the "red" has a bit of orange to it and the "blue" has a bit of aquamarine to it.

@BackSlash, I don't use this technology, I just did a search.  I haven't seen any other options.  I believe that this technology is presently in its infancy; so, there aren't that many options.  There also be other issues limiting this (such as Patents)

Daylight resin choice is extremely limited. And would not get much better at-least in short term. Majority of new LCD based 3D printers are using UV LED.
Checkout Wanhao D7, Phrozen3d and other newly released 3D printers.
I strongly advice you to checkout Ionel Ciobanuc progress on his printer.
He starts by making the first LCD based 3D printer actually works! to modify his printer to make it another UV LCD 3D Printer.
From the progress it is very clear why everyone adding UV LED to their LCD 3D printers.

ONO, as mentioned previously. But I do believe that resin will be rather expensive. Along the lines of $15 per 100ml. Since their resin sales are geared towards their printer (small, resin based printer that uses your smart phone as the light source) they sell smaller portions, as their printer can't hold all that much. Not quite sure if you can order larger quantities at a discount directly from them. But at this stage, they are rather difficult to get ahold of via internet communication. That may change if and when they fulfill their KS commitments.

$15 per 100ml is fine, UV curing resin costs up to $100/$150 per liter, so the price is quite the same. Do you know if there is any other manufacturer that provides daylight resin?

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


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cura shows different Z heights
Cura v2.5.0
I've been working in Blender for some time, so I have experience with exporting stl from it with exact size and I had no scale issues with slicing.
But today cura showed a strange thing.
These are 3dBenchy and a stretched cube which are supposed to have 45mm height, also "boundary boxes" are turned on to show that there is no flying geometry.

As you can see below cura shows same size visually but different in numbers.

And if I scale the ship inside the cura it will look like this
(low reputation) http://dl3.joxi.net/drive/2017/08/01/0001/2747/88763/63/969fe8bc67.jpg
Does anyone know if I screwed up the model somehow or can it be considered as a bug?

See this post, how to set scale on STL export in blender: https://blender.stackexchange.com/questions/7503/scale-settings-for-exporting-to-stl-for-3d-printing

Converted comment on OP to answer:
The comment links to a question on SE.Blender; the answer that led to the solution is quoted below.

The STL exporter doesn't take Scene Scale into account. Import your
  STL back into Blender (it will have the same size) and drag Scene
  Scale up back to 1.0, and you'll see how the cube grows relative to
  the grid.
1 Blender unit equals 1m, but STL seems to assume 1 unit as 1cm.
If you want 1 unit to be 1mm, set Scale on STL export to 0.1 and
  Scene Scale to 0.001 to make it match the output scale in viewport.
Note that the STL will be 10x smaller if you re-import it into
  Blender!

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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How to "paint" a mesh on a stl/obj
I have almost 0 experience in 3d modeling and I'm looking for a simple way to color a model.
I want to replicate this paint job of a model.
I've tried Blender, tried Mudbox and I don't have the money for Mari which is the software being used in the video.
The issue with both is that it seems to take forever to try and paint them. It's a high-poly model with a bunch of vertices. Both programs seize up and hang and I'm forced to quit them.
How can I simply and efficiently color the model to get it ready for sandstone color printing?

If you've looked into using Blender, you would have discovered that that program is free. It is also one of the better suited programs available for the task you've selected.
It's possible that your search terms may not have provided the best results for your objective. The task you describe is known as UV mapping, also known as adding texture to mesh, adding texture to a model. The generic term "texture" can be confused, as many people would consider texture to be the feel of a surface. Rough, smooth, slippery, etc., do not apply here.
Texture in the 3D modeling world applies to a surface description specific to visibility. In your task, texture refers directly to color.
Consider to search using the above terms or follow this lead:
Add texture to model Blender
Doing so provided a few quite well written links. One of the first to appear is an Instructable.
The above Instructable also links to a video, which is also a good location for learning basics for Blender and texturing models.
The above search also results in finding an SE entry directly related to Blender:
StackExchange Blender texture Q/A
Consider that you can create a flat image using your preferred graphics editor, placing shapes and colors as needed and then "project" or paste or plaster or project that image on the surface of the model in a controlled manner. This would be easier and faster than attempting to color manually individual triangles of the model's mesh. The SE link summarizes this process, although additional research is indicated.
Practice with Blender on simplified models and you should be able to grasp the necessary skills in short order.

I updated my question with better information.


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Low Filament Sensor for Creality CR-10?
I have been playing with my CR-10 for about a month now and I was wondering if there is a low filament sensor available for the CR10.
I found this listing on Amazon, Creality 3D Printer CR-10 S4 with Filament Monitor Dual Z Rod Screws 400x400x400mm, which is for the larger model which has a built in low filament sensor, and I was wondering if the sensor could be bought separately and installed on my CR-10.
Alternatively, I have had a look around and only found this, XCSOURCE 1.75mm 3D Printer Filament Detection Sensor Module Filament Run Out Pause Monitor for 3D Printer DIY Kit TE720. By looks of it, it needs to be attached to the main board in the control box.
Can anyone tell me if this would be compatible?

Have you had a look at your controller board?  Most importantly, does it have a large Atmel 2560 Chip?, that signifies the CR-10S board, that can accept the filament detector.

Hi HuwD, I have reworded your question to remove the opinion based part from it. I have assumed that you want to know how to get a filament sensor upgrade working. If I am wrong, then please feel free to roll back the edit. Join us in chat if need be.

TL;DR
You need to have the version 2.x controller board (and the associated CR-10S firmware) to use the filament sensor. If you do not then you will need to upgrade your controller board.

Board Comparison
For an excellent breakdown of the boards, read Creality CR-10 and CR-10S Models – What Printer do you have.
There appear to be two basic model versions of controller board, which use different firmware:

Controller board v1.1.2 (or v1.1.3 with additional filter capacitor) which uses CR-10 firmware. These have a small Atmel ATmega1284P chip, and one Z-axis stepper connector;
Controller board v2.0 (or v2.1 with extra fan ports) which uses CR-10S firmware. These have a large Atmel ATmega2560 chip, and two Z-axis stepper connectors.

See the section Board examples at the bottom of this answer for a visual comparison of the two boards.
It is the v2.x (CR-10S) board that has the filament detector, which uses the X+ endstop connector:

To quote part of the page:

Please make sure you know what printer you have. There are 8 DIFFERENT models from Creality. There are 2 different boards across these models. The easiest way to identify what one you have is if it has a filament sensor or not. If it does then you have a CR-10S machine. If it does not then it is a CR-10.
Just because you have a CR-10 S4 or CR-10 S5 that does NOT make it a CR-10S.
The S4 and S5 sizes come available with either board versions. Again the main way to tell is if you have a filament sensor from Creality or not. Whether you have Dual Z or not does NOT matter. What matters is what board is in the enclosure.
Typically every CR-10S board came with a filament sensor. So if you don’t have a filament sensor then it is the CR-10 and you need use the CR-10 firmware. However we have seen some CR-10 Mini machines ship with CR-10S boards. Use the below pictures of the boards that are in the wild to identify what model you have. The important thing is to use the correct firmware for the board that is in your machine.

Separate upgrade
With respect to the first question, you would be best off contacting Creality directly, via their customer support, to see if the sensor is available separately. This would probably make for the least painful method of implementing the filament sensor.
Alternatively, there is this kit, Creality CR-10S Upgrade Kit, for $120:

Best Upgrade Kit for your Creality CR-10 3D Printer contains Dual Z axis for Stability in 3D Prints & Filament Monitoring Alarm Protection (Sensor) which alerts you when the filament has ran out or broken for Smart 3D Printing

There seems to be a dual-Z option, for an extra $80

Hacked solution
For the second question, the XCSOURCE 1.75mm 3D Printer Filament Detection Sensor Module Filament Run Out Pause Monitor for 3D Printer DIY Kit TE720,

the instructions state that it is designed principally for Lerdge control boards:

Instruction:

When you are using a Lerdge brand motherboard: The green light on the motherboard will turn off when the filament runs out, the
motherboard will stop printing until you supplement the filament and
continue printing. (Please connect to the M-sensor Interface)
When you are using other brand motherboard: The Detection Module uses the level transition detection method. While there still have
filament in the module, the detection port shows as high level; when
there is no filament in the module, the detection port will transform
to low level as "Filament Run Out Command" which will stop the
printing, so you will have time to supplement the filament and
continue printing.

So, it is not particularly clear as to whether it will work with your board - for it to do so, your board would need to have:

A compatible input (i.e. X+ endstop);
The compatible firmware (CR-10S), and;
Use compatible logic levels (i.e. active LOW to shutdown printing).

If not, then given point #2, it would appear to require additional external logic, or microcontroller, to sense the transition to LOW and then shutdown the printer.
For example, this chap on Thingiverse, Cr-10 Filament Sensor Bracket & Tutorial, states that they bought a sensor off eBay, that looks similar, and they provide a printable mount and instructions on how to use it with a CR-10. However, it is not a standalone affair as shown in the CR-10 S4 - because an additional Raspberry Pi and OctoPrint is required.
To use this particular sensor with your board, you would need to:

See if which controller board you have - either the CR-10 or the CR-10S compatible board (see Board Comparison above). If it is the CR-10S therefore it has the compatible input (X+ endstop), and firmware, needed for the filament sensor,

Enable the use of the sensor, if necessary, in the firmware (either by the UI if possible or uploading new firmware) and;

Check whether the CR-10 controller board uses active LOW to detect a lack of filament (or again, this may be a UI, or firmware, setting)
You could test this last point yourself, by applying a LOW level voltage (i.e. grounding) to X+ endstop input on the control board (after checking the UI/firmware for appropriate settings), and see if that halts/pauses the print. If not, try a HIGH level (5 V). If it is active HIGH then you simply need to use an inverter (i.e. 4069), between the sensor and the X+ endstop connector.

Board examples
There are two principle board options, v1.x and v2.x, the latter has dual Z stepper motor connectors and the former does not .For example:
Version 1.x, for CR-10 firmware - Motherboard Controller DIY Creality 3D® CR-10 / CR-10S 3D Printer CR-10 Upgrade Control Board12V (CR-10S Mainboard)

Version 2.x (2.1 in this case) with Dual Z stepper connectors, for CR-10S firmware -  Luxnwatts CR-10S Mainboard Replacement Controller Board Upgrade V2.1 Motherboard For Creality S4 S5 3D Printer

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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Monoprice Select Mini v2 clogged Boden tube connection
I have had my Monoprice Select Mini v2 for about two weeks now and I get a clicking noise on my filament insert on some prints and when I check a few minutes later, I can see that it's not extruding and that there is a clog of some sort.
I checked to see whethere there was possibly a clog in my hot end or nozzle, but there was nothing there. So I checked my Boden tube to see if the filament was brittle and had broken, but I found that there was plastic with a slight twist clogged in the Boden tube connector. When it first happened I had used an Allen wrench to push the plastic out. The second time it was harder and took heating the connector piece up to melt the plastic and pull it out.
Now I know (from the ticking) that my gear feeder is making a clicking noise - as it did when it was clogged. So when I hear that, I just push the lever to loosen it and it sounds like it releases tension. So is there a way to stop this or prevent it? I tried upping the temperature on the nozzle but it didn't help much. I'm printing from an average of 60°C and a high of 80°C with PLA.

If you are heating your hotend to 60/80, that is WAY too low. PLA should be at 180+ hotend, and if you are using a heated bed, 60-80.
I would try increasing the heat of your hotend, starting at 180 and increasing if it looks like it is underextruding or if you get more clogs.


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Filament not feeding then eventually blocked
I have an ANET A2 Prusa - which I've setup and performed a few prints on and they have various problems with the quality.  I'm after some specific experience on what the flow of filament should look like or if my decription triggers someone
I've been adjusting settings - In particular the temperature - as the filament seemed too fluid as I could easily cause a large spurt of molten plastic by manually pushing the filament with very little effort.
So I reduced the head temperature to 195 and all seemed better
However after a time - I noticed on a longer print that the feeding was sometimes failing with the filament jerking back as the feeder slipped off it
The stepper did not appear to slip back just the gear skipped on the filament
It appeared to cause a problem in the print with a few of the lines being missing before it started extruding normally again
I increased the temperature back to 200 - however the issue continued intermittently however I left it and when I returned the head had become blocked with the final part of the succesful print consisting of very thin hair like extrusions and eventually stopping completely
The head is flooded and I need to clean it out
So my questions are - how runny should the filament look when the head is at the correct temperatures, is the extremely runny filament I saw at 200 obviously too hot - or is that normal or at least have people seen it looking like that when successfully printing?
Initially , before I reduced the temperature,  I doubled the skirt and that seem to make a good enough print
Does anyone have  experience of why it can seem to be printing but then slowly start failing until the head becomes blocked?

Extruder looks like mk8, isn't it? What plastic do you use?

PLA is what I've started with - the box says 195 -210 - but the setting of 210 gives very fluid  extrusions

It's ok for PLA to be more fluid than it's necessary to printing around 210 Celsius degree. Usually an optimal temperature for printing is in the range mentioned by manufacturers on a box, but need to be calibrated to reach the best quality of printed things. You can see how to calibrate nozzle temperature for PLA in this video - https://www.youtube.com/watch?v=FSOPsRiiOZk

From my experience with mk8 extruders lower than optimal nozzle temperature or clogged nozzle can lead to an extruder's stepper motor overheating and partial burning out of a stepper
It looks like “Achilles' heel” of mk8 extruders. I had to change 4 stepper motors for 2 3d printers with mk8 due to that
First symptoms – skipped steps. You could also check a temperature of your stepper – next symptom is a high temperature of stepper motor after several hours of printing
My fix for this issue – adding cooling fans to stepper sides and top (3 fans). It significantly reduced overheating and hopefully a life of stepper
Another solution of this issue can be in using of a stepper motor with gearbox to increase torque on a filament gear, so no high torque needed from stepper itself
About printing temperature, it depends on plastic which you are using
I’m using ABS plastic with an optimal printing temperature from 230-260 Celsius degree. For my current plastic supplier optimal temp is about 255 Celsius degree
To check the optimal temperature for your plastic you can print one box in different temperatures depending on Z position and found the optimal temperature by the z position of surface with the best quality. You can find code samples how doing it here
If a temperature is too high then this part of the box will be bloated, if it's too low - you can see the gaps. Here is the video, which illustrating this for PLA
UPDATE:
The issue was in the low temperature of printing. After calibration and setting temperature by calibration outcomes to 200 Celsius degree printer started working well
However, please be aware of the fact that wrong printing temperature can not only decrease the quality of printed things, but also can lead to wear of your printer parts and even can break it

The calibrate link you added is I think what I was after  - ie how do I decide if the print settings are correct

You can see it by quality of printed parts. If the temperature is too high - it's bloated, if it's too low - you can see the gaps. Here is the video, which illustrating this for PLA- https://www.youtube.com/watch?v=FSOPsRiiOZk

After calibration I found the best temperature was 200 ... so I had it too low

@Ross: That's good, thanks for info. I will edit my answer to add this information. So for now your printer is working fine, right?

Yes working well I've printed some large models and some complex ones and they print and have good adhesion and bonding. Thanks

From my experience with few printer, Sometime it's happen because of the filament.
Solution-
If your printer have unload function or if you don't have  that funstion select a printerable file and change temperature to  205-210 C and try to use long and thin hex key like this to push the filament out.
-Make sure you extruder motor work accordingly to feed the nozzle.

I'm getting some .4 mm drills to help - although I took the head apart and found just letting it heat up  - most of the plastic could be soaked out with pins

If you can easily push it manually, then it's hardly can help. I use drill to clear nozzle only if it's impossible or very hard to push it manually


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Noise Reduction
I am looking for methods to reduce the amount of noise produced by my CR-10. I have the printer in my downstairs study and if I'm doing a long print job, you can hear it upstairs in my son's bedroom and I don't want it keep him awake.
I've seen there are noise reduction feet available on Thingiverse but apparently these can result quite significant vibrations of the printer itself, which could mess up the print.
I've also seen one guy using a paving block but I'm not sure how effective that would be and also don't think my cheap Ikea desk would cope very well with having a concrete block put on it.
I was wondering about trying an off-cut of carpet. Has anyone tried this or have any other suggestions?

I do know about your budget, but I would suggest to buy a silent 3d printer like Prusa i3 mk3 which is about $1k. If you decide to tinker your printer instead than take a look on other possibilities:
Trinamic drivers
Most of the noise is created in motors.
Definitely switch to Trinamic stepper motor drivers. I have upgraded from Prusa i3 mk2 to mk3 last weekend and the noise reduction is significant, my estimate is 80-90%.

Take a look on this awesome blog post and video from Thomas Salanderer about the driver. Other good post is on instructables.
I would not suggest soldering unless you are a skilled hacker.
Better option is switch to different board.
Prusa i3 mk3 is using Einsy Rambo 1.1 for $120: https://ultimachine.com/products/einsy-rambo-1-1
But there you have to switch to 24V Power Supply Unit and you have to also switch to 24V heated bed.
Another solution is to use RAMPS and buy trinamic drivers separate (RAMPS doesn't solder drivers on the board).
Additional info about trinamic drivers: https://shop.prusa3d.com/forum/hardware-firmware-and-software-help-f64/tmc2130-driver-infos-and-modifications-t15835.html
Pad
Use a concrete paver as described in this youtube CNC Kitchen channel. It reduces noise by 20dB (not if you use trinamic drivers).

https://www.cnckitchen.com/blog/reduce-your-3d-printing-noise-with-a-concrete-paver

Enclosure
An enclosure should also help to reduce noise.

How to build enclosure from Ikea table: https://www.prusaprinters.org/cheap-simple-3d-printer-enclosure/
Dampers
Dampers help you reduce noise. There are two types of dampers:

Motor damper:

Printer dampers: https://www.thingiverse.com/thing:2103227 (thanks to Sojtin)

Video about silencing the Prusa i3 MK2 & Horrible Vibrations:

The dampers are useless in combination with Trinamic and they also reduce the cooling of the steppers. Also, if the issue is noise from different floors, the stepper drivers won't help because the high frequency vibrations are not transmitted much between rooms. Lower frequency vibrations are.

Great answer. Two things. First, stepper dampers as depicted could also decrease the print quality. You want a stiff connection between stepper and drive. On the other side, if belts are used to transmit the movement, it also has a little flexure. Second, the depicted base damper, is this a damper or a spring? What dissipates the energy?

Personally for vibration reduction I use a large mouse pad I cut to size, but I'd imagine the carpet would perform just fine. I would also recommend enclosing your printer (this had the most profound effect for me) and upgrading your stepper drivers.

Have actually gone for a piece of foam exercise mat. Has definitely made a difference. Unfortunately don't really have the space to enclose it.

I use a paving block with rubber feet underneath it on the floor. It is very effective: The 3D printer is sitting right beside a door, and you can't hear it printing from the other side of the door.
The low-frequency sounds are definitely absorbed by the paving block. What you can hear now are only the hissing sounds, when the extruder glides along the rods.
I wouldn't put the paving block on a table, though, or anything elevated, since that will only magnify the lever effect of the table legs and exacerbate vibrations.

The pavement block dampens higher frequency conducted sound of the stepper motors and prevents them from amplifying in the table (like a guitar). While the rubber tiles dampen the low frequency sounds due to things moving. Only fan noise is left. I got a 15 kg tile and workshop foam tiles.

I use a 2.5 cm thick granite slab with clumps of cushion foam under it. Reduced the noise level by about 15 dB (measured by phone app).

Change DRV8825 / A49nn series on board stepper driver with Trinamics TM2100 ( in silentChop mode) will make your step motors almost silent. They are outstanding.
But there are couple of disadvantages:

There is chance of losing steps in slientChop (Would not effect print quality in my experience)
TMC2100 is 5-6x times more expensive than DRV8825
Require soldering and electronic knowledge
TMC2100 runs hotter

Looks like a good solution. Not sure I want to go to that much hassle right now but will definitely keep it in mind for future upgrade.

The Marlin bug trackers have epic threads on folks losing steps and getting layer shifts from stealthchop (silentchop?). I would be very wary of using that feature.

I have an Anet A8 and these vibration dampers do a great job:
Thingiverse: Vibration Damper for Anet A8

Hi @Sojtin I am on the edge on deleting this answer. As it is getting upvotes I will keep it. The issue is it cannot really stand without the link to thingiverse. That model could one day be deleted. See stackoverflow.com/help/how-to-answer for more information

Is this a damper or a spring? What dissipates the energy?

I had a similar problem, the neighbour started to complain. I solved the problem by putting scourers under the table where my printer was placed on top of.

They are mildly effective, but very cheap. They were 7 cents a piece at my local supermarket.

Rubber mat for laundry machine works even better

If you hear it from a floor to the other the only thing to change is the base of the printer. Nothing else matters.
CNC Kitchen performed measurements especially to avoid noise being transferred to other rooms, the result is that placing the printer not on elastic feet, but on a single slab of concrete which is placed on top of foam is the best solution and reduces the noise significantly.


text:
Is it possible to print a resonator for a musical instrument?
I play a berimbau for Capoeira. One of the most fragile (and most expensive) bits is the cabaça, a hollow gourd used as a resonator.

I'm not very familiar with the qualities of the resin used for 3d printing. If I were to take this to our local Maker Lab and have them scan and print a copy, how likely is it that it would work? My fear is that the plastic would be too sound deadening.
If you want a less exotic parallel, imagine the body of a guitar. That's a resonating chamber.

"Scan and print a copy" -  It doesn't work like that. It will be "scan, spend hours remodelling the part to obtain a printable file using the scan as a reference, print".

Shows my ignorance. What if I just started out by modeling it in a program? My question still stands on whether plastic works for resonating.

Of course it's possible to print one; but until someone does, we won't know how well or poorly it resonates.

Best case scenario is someone had done it before. :)

There are a ton of ocarina models available online, along with various other hollowbody instruments.  The relationship between wavelength and resonating power is absurdly complicated, depending on material properties, material cross-section, cavity shape,and so on.

Side note, I have since printed a resonator from a publicly available model, but I did not get a chance to try it out over the weekend. I plan to try it tonight.

I can't answer this from a technical 3D printing angle.  But, from a musical angle:
Where the body of an instrument has the primary function of enclosing a vibrating air column, the material has often been demonstrated to perhaps make a difference, but only a subtle one.  As an example, a recent range of plastic trombones, although not first-class instruments, have proved extremely playable (and have the great advantage of being virtually indestructable).
I suggest you try this.  Play your instrument, dampening vibration of the cabaça with your hand or with a piece of cloth.  Just damp the shell externally.  Don't obstruct the hole or put anything inside.  Now, fill the cabaça with cotton wool or similar.  If the first makes little difference, you're probably good to go with a plastic cabaça.  Of course, if the second makes little difference either, we might have to suspect that the cabaça is mainly decorative!
You could also experiment with alternative resonators of a similar size and capacity, available 'off the shelf', not worrying too much about a cosmetic match.  They might sound even better!

Using plastic mostly affects the tonality and has little to no effect on the playability of the instrument. Does this sound correct to you?

Following up on this, the answer is, yes, this works quite well. I printed this cabaça model from Thingiverse using PLA on a Lulzbot Mini and put it on my berimbau today to test it out. I can't make a direct comparison because the printed resonator is smaller than the gourd one that I own, but the sound is good. I am not certain whether it is actually cheaper (it used a fair amount of PLA because it's probably about a half-inch thick, and it took a few tries to get a good print due to it taking about 9 hours and needing to be monitored for the filament breaking), but it may be more accessible for people who can't ship a gourd in from Brazil. It is definitely more durable.
 (click to enlarge)
 (click to enlarge)

the breaking filament might be more a thing of how you feed the filament and your filament quality - drying it for a short time in the oven and proper storage can prevent this.

Here is a great answer to the underlying physics of resonance:

"A object rings because it has acquired energy in a way that it resonates - it vibrates at a frequency and with enough energy to generate sound waves. As long as the object has sufficient energy, it will continue to ring. It cannot ring forever as the sound waves gradually reduce the amount of energy that the object has. But generating sound waves not the only way that an object can lose energy, One of the ways that plastics differ from metals is that plastics are better able than metals to dissipate energy internally. Any plastic object will show some amount of viscosity dampening since all polymeric materials have a non-zero loss modulus curve. Metals can also have internal dissipation mechanisms, but they are far less prevalent than in plastics."
So, we all know it, you can make plastic musical toys.  They never resonate as well as metal, glass, or wood; but, they often can work.  Here is an example of a Trumpet made out of ABS!

This plastic's magazine also makes it's pitch for using plastics in musical instruments (most of which is also ABS).
That said, if Young's Modulus is the key (as the first comment said), PLA should be even better as its' Young's Modulus is a bit larger than ABS.
All that said, all the plastic bells I have seen are generally pretty quiet. Plastic has a habit of absorbing energy and thus not being a very good resonator.  If you want to try, I think you are going to have to find a way to harden the plastic.  Maybe Acetone treated PLA as that seems to harden it.  Maybe try something simple like printing a plastic bell.  If you can get that to ring, you are well on your well.

I'll take a stab here, but my gut instinct is to say that a printed part will not sound the same as your original gourd resonator.
I believe the acoustics rely on the hardness, shape, and size of the material. In which case, a gourd is a hard and often thin material (after gutting it). Typical 3D printing materials will have a minimum thickness which may get in the way of achieving the same shape of the gourd resonator and plastics are typically going to be softer in hardness than your gourd.
So, in short, I think if your try to replicate the resonator with 3D printing it will not sound the same. That may not be a bad thing, depending on what you're looking for.
Also, who's to say the resonator has to be shaped like that? 3D printers allow us to manufacture parts that have historically been impossible to make and many instruments that we use today were designed hundreds of years ago with far less advanced tools available. I say its worth trying a replica of the gourd and then exploring other shapes to print that may affect the tonality of your instrument.

Of course. I've printed a 7 octave organ rank, so it's certainly possible. Organ pipes are quite special in that the material properties of the pipe play a secondary role in the tone, the primary role being played by the length and cross-section of the pipe, the elements surrounding the mouth of the pipe, and its other openings (end opening, and extra openings that sometimes are used to modify the overtones). It's also well understood how the pipe material properties affect the sound, so it's possible to design the printed pipe to mimic properties of either a wooden or a metal pipe, and anything in between.
Depending on how big of a role the resonator's stiffness plays in the sound of the instrument, you might need to replicate some of mechanical properties of the Gourd shell - e.g. its stiffness - in the printed shape. Thus the inside of the print will have the shape of the inside of a Gourd, but the exterior may need to be much farther away, and then the infill percentage will play an important role, as well as the infill shape.
The shape of the interior of the gourd can be approximated by measuring some dimensions and sculpting an interior surface in a 3D modeler or CAD. Most likely a 3D scan is not necessary, unless you can get it done cheaply and with no fuss.
You will also need to print full-size instruments. So this will not be cheap in terms of material used and printer time. I would benchmark the printed instrument at 3 shell thicknesses: 0.5, 1.0 and 1.5 inches, and 3 infill percentages: 20%, 35%, 50%. All with 3 perimeter layers, and cubic infill. The thick 1.5in shell with high infill will be the stiffest of them all.

If an instrument sounds "right" has as much to do with how it is shaped as with how the material it is made of is layered - or not - as this changes it resonance. Let's take a few examples:
Metal, cast resins & hard woods all are very dense and contain (little to) no hollow spaces to dampen their resonances. This makes them the classic choice for making instruments, as just the shape changes the tune now.
Balsa wood is very very light and brittle, and it is very grainy, creating some hollowness inside the wood that should resonate, changing its resonance a lot.
I don't exactly know how the gourd is in its composition, but for percussion perposes, 3D prints are more on hollow side than on the hard wood side for low infill. Very dense (35%+) prints can have similar properties to solid resin casts, but this depends on the type of filament and printer used.
Let's look for a compromise!
From my own experience with musical instruments, there is a vougue of carbon fiber reinforced resin instruments in classics. In broad strokes, these were manucaftuered by casting resin over carbonfiber mats pressed in to a mold and then sanded and polished. In other terms, 3D printing of carbon fiber filament is around in the FDM scene, even if it highly abrasive and demands a nozzle like the ruby to print.
With the right interior design (that is, an almost hollow print that just contains struts that don't seperate cavities inside the print), a carbonfiber print could possibly be filled with resin and become a 3D-printed composite, granting a much closer sound to the gourd while providing extreme durability.
However, such a design will take many hours of work before the first print can start. Atop that printing carbon fiber is a specialty thing not many print shops can do or do regularily. And finally, the postprocessing of filling the "gourd shell" with resin is a very delicate process, followed by coating inner and outer layer and then tuning... I estimate such a thing to be at least as pricy as several real gourds.
Addendum
After some months and this question popping back up, I realised some more things that might be used in the design of this:

Thin shell, armored up. Think about this the following: Print a 2 or 3 shell thichk wall, that will be the most inner. Then reinforce it with resin and carbonfiber mats until the sound is right. This would allow to tune the gourd to some degree.

Solid print, slidified. You might take your model and print it solidly, yet in the design you could include tree like hollow spaces that are accessible from the outside. with a syringe. Pushing in resin via these holes would create veins of harder resin within the gourd, which might alter the tune and strengthen it.

Postprocessing. Ignoring the resin for a bit, you can also make a PLA gourd more stable by allowing it to cure in the oven for some time. I had some success baking it at about 100°C for about an hour. For mor information on how this changes the modulus of different materials, I suggest CNC Kitchen: Thin Walls & PLA Annealing and Changes in annealed PLA


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How thick does an aluminum print bed need to be
I am extending the bed of my TronXY X3 FDM RepRap printer.
I am extending the bed from 220 mm x 220 mm to 220 mm x 300 mm.  For now, I will keep the existing bed and add and aluminum sheet on top.  That leaves 40mm on front and back of the original bed.
Right now I only plan on running PLA; but, I do plan on heating the bed.
How thick does the aluminum sheet need to be?

You are adding 380mm to the size of the bed, and that only leaves "90mm on front and back"? Is that a typo, and did you mean 190mm? It doesn't sound like a very good idea to just put a big slab of aluminium on top of your existing bed, because it won't be very rigid and will vibrate all over the place. I think you should change to a different carriage design if you want to do this.

@TomvanderZanden the real typo was that I said 600mm when I should have said 300mm.  600mm would have been a HUGE base - COOL but un-realistic for an X3 base.  Regarding attaching the aluminum to the plate, I attach my glass plate now; but, then you were probably referring to my description of a plate that had more unsupported material than supported.  With the right numbers, the overhang is small compared to the overall size.

@TomvanderZanden I found a random piece (23" x 6") of 1/8" sheet aluminum, paper-clipped it to the bed and started printing on it tonight.  Funny that it is almost as long as my original 600mm typo.  I figured what the heck, best way to see what I learn.  Getting it leveled was a bit challenging (I don't have auto-level) - several failed prints (some of which were exasperated by not getting glue stick down everywhere).  Print is 245mm long - so just a little longer than the original bed.  New "bed" overhangs over 4" in front and back.  Pretty comical - but it works. ;)

I have a 3 mm thick 120 x 120 mm plate and it bends while heated: the small size means that the edges get cooled faster and contract in respect to the centre.

Main factors that control the process of the print bed selection are

weight: too thick plate increases inertial force, limiting maximum acceleration/jerk (decreased print speed)
stiffness: too thin plate will warp when heated or bend during calibration (decreased print quality/printer reliability)

For table sizes around 400x400mm I would think of 4mm plate, but it still can warp if heated unevenly.
Sometimes it makes sense to use a sandwich-type table: lower level is MDF, cork panel for heat insulation and thin (1.5-2mm) aluminum heated bed on top.

A sandwich table is great for higher bending strength at a lower mass.  Heating it can be a challenge, as most of the interior materials are relative insulators.  You could consider a layered structure with a PCB/heater on the top layer, something light but incompressible for the middle, and more PCB without the heater traces for the bottom.  What to use for the middle?  Ideally, something like an epoxy similar to PCB material foamed with air and hardened.  Maybe an epoxy/pearlite mix.  If you have a CNC router, you could make a gridwork of PCB strips on edge.

I build an 18.5" diameter delta printer.  The bed was 3/8" thick 6061 aluminum.  It is plenty stiff, but it takes an hour to heat to 100°C.  When I rebuild it, I'll probably drop down to 1/4" and increase the heater from about 250 Watts to 750 Watts.  That should heat the bed in 15 minutes, which is still a long time.  Waiting for the bed to heat for ABS is one of the greatest frustrations with that machine.
For your machine, how much the 1/8" plate bends will depend a great deal on which aluminum alloy and temper you use.  From OnlineMetals.com, 6061-T6 and 7075-T6 are available.  7075 is slightly stiffer, but both should be good enough.  6061 is half the price.

Delta printers have the benefitial bonus of not needing to move their bed, which makes mass irrelevant but for the thermal mass and stiffness in question

I highly recommend aluminium tooling plates. They have a +/- 0.1 mm flatness tolerance on 1 meter. It's alloy 5083 offers a great stability. You can purchase such for example at aluminyumburada, which offers custom cut piecees.. They have a minimum thickness of 5 mm, though the prices get lower the thicker the piece is.

The answer should be about the thickness, is 5 mm the correct one or should it be thicker? why? I think you actually haven't answered the question.


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Converting a mesh to constructive solid geometry
I have a mesh of a bowl that has the perfect shape of half a sphere. I want to easily convert it to the containing sphere solid and a box solid that will be subtracted from it.

Googling mesh to solid shows that in various tools such as 3ds Max, Fusion, etc., manual approximation of where the sphere might go is created manually by visually comparing to the mesh or the cross section when creating the solid but I am looking for the minimum enclosing sphere and box to be generated/calculated by the software.
Source file format is of course not an issue, it can be any known mesh file.

The answers by @markshancock and @fred-dot-u describe the process of creating a CAD primitive sphere and subtracting a cube; this is a trivial task in most any 3D CAD program. You could manually measure the mesh to determine its dimensions, and frankly, I would recommend this approach. (If you have a large task like converting 100,000 half-sphere meshes, I'd re-think the approach and go to the source that generated the meshes in the first place!)
However, these don't address converting the mesh to a primitive, which is normally not possible for arbitrary meshes (therefore a CAD program will not have such a function), and much more difficult than simply measuring and re-creating.
You assert that your mesh file "has the perfect shape of half a sphere". A mesh is basically on a collection of vertices, joined by edges and faces. The vertices are defined by numeric coordinates, and in a computer will always have some rounding errors, and the linear edges and planar faces are most definitely not round. Therefore, it may be incredibly close, but it will most definitely not be perfect.
In this very particular case, the diameter of the sphere is the same as the diameter of the circular face of your half-sphere. You could plausibly write a simple program that would locate the maximum distance between any two vertices in your mesh and use that for the diameter. The midpoint of the line between those two points would be the center of the sphere. This should produce a good result but may not be "exact" depending on the details of the mesh.
I won't try to explain how to create the actual program as that is not in the scope of 3D printing.

The calculations for your objective could be considered simple geometry, although the results in terms of formulae are a bit more complex than simple, but not by much.
According to Quora, the foundation for this goal is that the cube's eight vertices will be coincidental to the sphere's surface. If one desires to print a 3D object with this form, such an object may fail the requirement of being manifold, but may not, depending on the floating point operations of the software being used.
I found a simplistic formula which provides the radius of the sphere given the length of the side of the cube.
$fn = 90;
edge = 10;
cube([edge, edge, edge], center = true);
sphere_radius = sqrt((3 * pow((edge/2), 2)));
sphere(sphere_radius);

The above code is done in OpenSCAD, resulting in this image with the sphere made transparent for clarity:

Translated into general English, it appears that one can take the edge length, divided by 2, then take the square of that result and triple it. Take the square root of that value and it becomes the radius of the sphere.
The above answer is courtesy of Math Forum and is represented verbatim as such:
        ____________________________
  D = \| (L/2)^2 + (L/2)^2 + (L/2)^2

The letter D in this case appears to be slightly misrepresented as diameter when it should be referred to as radius.
As part of this fun exercise, I also subtracted the cube from the sphere, slicing it in half for visibility, resulting in this image:

So it depends a lot on what you want to do.

If you want to mathematically calculate what cube fits in what size sphere, that is straight forward.  The diagonal for the cube has to fit into the diameter of the shere.  For a cube with edge 'l' and a shpere with diamamer 'd' then   <= d.
If you want to model a cube and a sphere in CAD (or one inside the other) you just do it.  They are both primitives.  Takes less than a minute.

You can use a mesh in a design too.  I would assume if you are wanting to use a mesh, the mesh must contain something other than just a smooth bowl or what the point of the mesh?  Fusion 360 allows you to import a mesh and play with it just like that and combine it with model objects (just like the box).
You can actually convert a mesh into a solid model if you want to too.  Fusion 360 CAD has ways to help you convert that mesh to a sculpt.  First create a sculpt object that represents the shape of the mesh object (like a sphere or a quadraball).  Next import the mesh then collapse the model over the mesh (using it like a model to form a mold).  You can then delett the mesh and use the molded sculpt.


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How is the print time of an object to be printed estimated?
I am curious about the algorithm/principles behind the estimates that the slicing softwares provide. Is there a standard technique behind this and how accurate is it ?

And let's not forget the psychological part: the beginning of a print always seems to take forever, partly because there's little in the way of recognizable shapes.  The last 25% or so of the layers , not only is the shape quite visible, but typically these layers cover much less area than the base, so the time per layer does decrease.

Generally speaking, the typical algorithm takes into account the slicer's speed settings for specific features of the build, such as infill, perimeters, top/bottom layers, etc. The distance traveled by the nozzle at a specific speed for each feature is also part of the equations involved. There are some rather vague portions of the nozzle movement based on acceleration and other factors which makes the calculations less accurate.

How accurate is it?

Not too accurate. My experience with three different slicers is that it's never been within better than ten percent. I believe the various combinations of features of a build are not going to be identical from one model to the next, preventing even a ballpark figure to be created from previous builds.

Can you provide a reference where one could see how these calculations are made ? Like a piece of code or the algorithm itself.

Tom van der Zanden's answer is a bit more convoluted than I can follow, not being a code person, but is a good start. I've found a number of web sites containing basic descriptions of calculations, including http://forums.reprap.org/read.php?2,647001 but all of them appear to be missing various factors. In most of the sites, the acceleration is ignored or approximated. As a result, the build times are approximations. I suppose if one were applying orbital dynamics mathematics to 3D printing, one could get more accurate results.

Unless you're dealing with multi-day prints, I'd say 10% is more than adequate accuracy.

Much of the software used in 3D printing is open-source, and so are some slicers. Cura, for instance, does (or did, this source code is from an older branch) its print time estimation in gcodeInterpreter.py.
The relevant portion of the source code is (simplified and with many lines removed for clarity):
    totalMoveTimeMinute = 0.0
    pos = util3d.Vector3()

    for line in gcodeFile:
        G = self.getCodeInt(line, 'G')
        if G is not None:
            if G == 0 or G == 1:    #Move
                x = self.getCodeFloat(line, 'X')
                y = self.getCodeFloat(line, 'Y')
                z = self.getCodeFloat(line, 'Z')
                e = self.getCodeFloat(line, 'E')
                f = self.getCodeFloat(line, 'F')
                oldPos = pos.copy()
                pos.x = x
                pos.y = y
                pos.z = z
                feedrate = f
                currentE = e

                totalMoveTimeMinute += (oldPos - pos).vsize() / feedRate

As you can see, (this version of) Cura simply:

Loops over all the G-code instructions,
Computes the length of each move (in X/Y/Z) and divides that by the feedrate to get the time that move will take,
Sums this up over all the moves.

and does not take into account:

Acceleration or deceleration. It assumes the printer is always operating at the maximum feedrate,
The length of filament extruded. The feedrate is the speed for the move in (X,Y,Z,E), but Cura only looks at (X,Y,Z).
The time it takes to heat up the print bed/hotend or homing/autoleveling,
The effects of the printer slowing down if moves can not be read (from USB/SD-card) sufficiently fast (though this would be rather hard to include in any estimate).

The accuracy of this estimate can be arbitrarily bad if the feedrate is set to some unrealistic value.
Newer versions of Cura use a much more advanced time estimate method, and it can be found in timeEstimate.cpp.  It is much more complicated, and actually takes jerk/acceleration/deceleration into account. It is much more accurate.
We know exactly how 3D (open source) 3D printer firmwares work, so estimating print time is as easy as simulating execution of the G-code by your given firmware. There is no reason you can't get a really good estimation (if you take into account all of the intricacies of your given firmware's acceleration/deceleration techniques) but writing the code for it is rather involved.


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How do I upgrade (copy settings) from Cura 2.5 to Cura 2.6?
On my Mac I've got two versions of Cura installed, in /Applications/Cura250 and /Applications/Cura262.
How can I copy my printer and profile settings from Cura 2.5 to Cura 2.6?

Ya got me - I upgraded and IIRC there was some option to click to import settings, or maybe they just got imported automatically.  DId you check that your setups are not available?

Yep... only shows a default printer in 2.6.  I'd be content knowing if I could copy some config files from 2.5 to 2.6.  Or maybe this will be a feature in 2.7.

From the Ultimaker Forum:

Launch Cura 2.6 and go to Help -> Show Configuration folder. Now close Cura.
These are the configuration files for Cura 2.6. They are in a folder named 2.6.
On OSX, the configuration files for Cura 2.5 are one folder up (not in a folder named 2.5). You can copy files from that parent folder into the folder named 2.6, and Cura should update them as needed the next time it is started.

side note: Cura still forced me to create a new printer via an uncloseable dialog window, even though my previous (non-network) printer showed up in the list afterwards as well. The trick otherwise works great +1

Hope this is all you need.
From the release notes page

Cura 2.6 - June 20, 2017 Local version folders. When installing a new
  version of Cura, a new local directory will be created to make it easy
  to access old configuration folders and return to old settings if
  necessary.

So if you know where your current 2.5 config directory is, you should be all set.

So... How do you copy the settings? Move the files from one folder to the other?

@TomvanderZanden I wouldn't move the files, but copy them. Once everything works fine and you're happy with the new version, feel free to remove the old settings folder.


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PLA continuous operative temperature
For personal usage, indoor, I'm doing some experiments with following lamp (v0.1):

Lamp is a led bulb enclosed in a methacrylate tube and with a 3D printed finish at the top using PLA (my first 3d print ;-).
In some www pages (by example, here) I've read that the led buld radiator can reach 90º C. Experimentally, the methacrylate and the PLA feels only slightly hot, I suppose around 40ºC.
According to www info, PLA has a melting point of 150ºC, far from this usage, but a continuous operative temperature of only 40ºC ( !? this made 3d printing unable in a country as my own one, where ambient in summer is around 40ºC).
So, my question, is PLA a valid material for this application? If not, some other one better?
Thanks a lot.

Note that if (as it appears) your "3D printed finish" is blocking airflow for the LED radiator, it will negatively impact LED lifetime (the hotter they run, the faster they fail)

@Ecnerwal: it is true, to minimize this effect, the narrow part of the piece has some margin around the cable, allowing some airflow. Taken into account your comment, I will add some holes in the horizontal layer of the piece to increase airflow.

EvilTeach's answer is correct, ABS is a more reliable plastic for any kind of work which may get above what feels "hot to the touch."
Just to elaborate on the why: the property you're looking for in the thermoplastic (which will determine the continuous operating temperature) is glass transition temperature. This is the point at which the plastic begins to flow, and becomes deformable as EvilTeach described. PLA reaches this state at around 60 °C, whereas ABS is around 105 °C, just suiting your specifications. To go a bit further, polycarbonate offers a glass transition temperature of around 150 °C, and Ultem at 217 °C. So there's a thermoplastic for everyone, you just need to know what you're looking for!

I had a PLA print that would weaken and deform when sitting in the car on a hot day.   I think you should try it with ABS.


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Monoprice MP Mini Delta - How to get started?
I just got a Monoprice MP Mini Delta from an Indiegogo Campaign, but it came with no printed docs.
How do I get started?

Updated Manual

Turns out an out of date manual was on the sd card that was included with the printer. But it was definitely out of date, as it referenced UI items that don't exist, and files that weren't on the SD card.

An updated manual can be found here
or possibly out of date here

Resources and sample files

A very helpful Facebook group has a bunch of files that are good sample prints. If your manual says you can print a cat.gcode you've got an old manual.
Note: Don't try and just google cat.gcode as I did. The model I found rammed the print head right into the bottom of the printer. The correct model works great (actually called auto00.g on the SD card)
Another great reference site appears to be https://www.mpminidelta.com/, and this reddit

Common Problems and Solutions
The following are some problems I had and their solution
Can't print custom models
If you find you can print prebuilt gcodes fine (cat,viking,toothless), but can't seem to print any other models without the print head ramming into the bottom of the printer and going off to the side, you probably haven't setup the autoleveling gcode that's required. You can add something like the following line to your software, in a "startup" gcode section. This is detailed in the manual (just search for G29), and more info can be found here
; auto-levels the build plate with a overall vertical
; offset of 0.3mm with a center offset of -0.8mm
G29 C-0.8 Z0.3

First layer doesnt stick
If you find your first layer isn't sticking, or it seems like the plastic is balling up, you need to adjust your startup gcode line mentioned above , so it has a lower Z offset, like Z0.25 for example
G29 Z[offset] ; raises
G29 Z-[offset] ; lowers

Notes

Please try a positive offset value first.
Each printer will require fine tuning in regards to the offset value.
Start with a higher value and decrease as necessary to get good first layer adhesion.
Using a negative offset value may send the nozzle digging into the build plate.

This is effectively a link-only answer; on its own it does not contain any useful information for someone looking to get started. An answer is supposed to answer the question and, in this case, should help someone get started. You're just pointing the reader to other websites to get the information they need.

There's lots of info here - manual is on sd card, manual is very out of date, where missing files can be found, sample similar files on the internet cause printer to malfunction. That's information - did you know the answer to those questions before you read this answer? True that this ends up being links as well, but I asked and answered the question as it took me about 45 min to get my printer working by googling and trying to find info, and I would've appreciated this answer myself. Thanks!

I agree and don't know what the first guy was tlaking about, unless this answer was majorly upgraded.
I mean it even gives gcode to solve a problem.

In his defense, it has been upgraded as I found more issues that were problematic (gcode being one of them!), but I still thought it was relevant enough to warrant a post ;-)


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Why are Carbon 3D are not selling a home version?
Carbon 3d made a 100x faster printer which has a simple and cheap mechanism using a Teflon layer. It appears to have a 20mn in RnD Costs and $7000 mass market production cost.
The only access method for one is a USD$ 161,250 yearly subscription.
Their printer is not available in shapeways... Is there something wrong with  Carbon 3D so that it does not view consumers as a direct market, and has no market news on it's website?
How can they spend 222 million in investment money and not have a 3d printer in shapeways or public access?

This reads more like a rant than a question.

OK sorry I summarized the question. I believe that their investors don't want people making shoes and other expensive items easily at home.

I will take the question seriously, and consider reasons why Carbon 3D might choose to offer their technology through a yearly subscription, rather than building a product accessible to the consumer market.  These reasons are speculation and do not reflect any specific knowledge about Carbon 3D, the details of their technology, or anything unique about their corporate mission.
1) The mission of a company, especially in the beginning while competition makes it possible, to make as much money as possible.  If the technology is unique and brings good value to a large enough set of interested customers, it can easily consume the full attention of a company to service those customers.  The price those companies pay for access may be higher than others would pay because their derived value is higher.
2) If a technology is new, and perhaps still somewhat immature, there may be very high support efforts and cost required.  Through this time, the learning curve does it's job, the technology improves and matures, and the costs go down.
3) If the technology is immature, and perhaps is evolving quickly, it could be to the advantage of a supplier to only offer the technology on a service rather than capital acquisition basis.  It simplifies replacing components.
4) If the technology is immature, selling the service may be easier than selling the hardware.  It simplifies the acquisition process, and makes it easier for customer's to expand their usage since the supplier's capital is used to finance the machines instead of the customer's.
5) Even with a mature, proven technology, it can be advantageous to maintain a higher price point.  The game is optimizing the profit on volume times price.  The point they operate at is influenced by their perception of the market.
6) In the early adopter phase, it is critical that the customer experience be stellar.  They may be limited in how rapidly they can scale in some critical dimension -- consumables supply chain, manufacturing capacity, trained installation technicians, local service offices, or many other limits.  Anything going wrong makes for a bad customer experience.
It doesn't surprise me that they aren't going after the consumer market at this time.
But, I'm not in the CEO's office, and I don't see where his pain comes from.  My purpose here is only to propose some plausible reasons why the company has not launched a consumer facing product.

Thanks for your rationale. The 1/ condition suggests that Carbon 3D management isn't about changing factory-consumer industries, that it is there to protect multinational companies from losing the current made-in-China/Bangladesh by Nike and Tomy status quo... I believe that they have a 7000 dollar, variable cost, teflon film product, which requires 10mn RnD and it's their call to make it ubiquitous.

I don't accept your assertion that they are there to protect Nike and Tomy, or China, or Bangladesh, and was not the emphasis of my first speculation, which is that Carbon 3D's first mission is to develop Carbon 3D as a company.

It looks like they have only one innovation: their resins. Everything else looks like standard SLA.
All the things Carbon 3D are pitching on their website are more about having a dedicated support team than some fancy printer, and that's what they're selling.
As to why they don't make a home version: why would they? It's at best a distraction from their core business.


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How to prevent layer separation, when printing tall vase-like (tube) objects?
I am experiencing a minor layer separation when printing a body for a tipping-bucket rain gauge, which is basically a hollow tube with thin walls (3 mm). I am using Prusa I3 MK2 and a Fillamentum ABS white plastic. The model has been sliced in Siplify 3D with the following settings:

layer height: 0.2 mm
perimeter shells: 3 layers (almost entirely
fills up the wall)
extruder temperature: 230 °C
printing speed: default - 50 mm/s, outline - 35 mm/s, infill - 35 mm/s

Is it possible to prevent the irregular and layer separation by adjusting some of the settings, and not significantly increasing the printing time, which is already 13 hours?
PICTURES:

Do you need to use ABS, or could you try PLA, which is easier to deal with and might meet your operational environment needs?

such a large print needs a heated chamber.

Yes, it needs to be printed from ABS due to its better UV resistance. @Toonils it seems to be the problem. Thank you, I will try to create the chamber.

If the level of detail you need is not too fine, perhaps using a larger nozzle - should make for faster printing and will reduce odds of clogs/partial clogs and should improve layer adhesion (more hot plastic sticks better than less hot plastic.)

The best thing you can do for a large ABS print is to have an enclosure heated to 50C or better. For example, see this, this, this, and other search results.

increasing the temperature by 5 to 10° as well as, increasing the layer thickness to "0.3" or "0.35" may assist ,additionally increasing the flow rate of the filament, by a small margin at most 10%. These options should improve the quality of the print as they improve the layer adhesion, however none of these options will completely solve the problem.
alternatively you can repair the current print. In order to do this you will need to use something cot such as a soldering iron with a variable temperature, to melt and rejoined the layers. similarly you can use a 3d pen to apply additional plastic across the sections of separation in order to repair it.


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How do I convert point cloud data to DICOM?
How can I convert 3D point cloud data to DICOM format (specifying slice width) or an equally scrollable sharp 2D image format?  Which software (preferably opensource or free) can I use to do this?
I've searched on Google and can't find anything.
Chris

This is almost something that could be done in an afternoon from scratch... What is the 3D point cloud data format? What sort of a DICOM output do you want - be specific, there are several possibilities!

This answer is actually based on combining answers from 2 other questions (this and that).
The process isn't a single step and would be to as follows:

The point cloud data needs to be converted to a 3d mesh.
Convert the mesh to STL.
Slice the STL into SVG.

For step one, the type of point cloud data would decide the software to use (for example, if it is GIS point cloud data, or 3D scanner point cloud data). A good end result of step 1 would be a VRML file. As you've not specified the type of point cloud data, I cannot suggest a software for it.
Step 2 would be to convert the mesh to STL which is easily doable using  Meshlab.
For step 3, Slic3r itself will work just fine to generate the SVG output you're looking for.


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Which 3D printer is good for beginners?
I was looking for some advice on which 3D printers are good for someone who is just getting into 3D printing?
I have been looking at the Anet A8 on ebay but not sure if they are any good or not.
Regards

the Anet A8 is a great machine. I would highly recommend it.

I am voting to close this question as being too opinion based. It is extremely open-ended, with very little details to narrow down the search. In general, I think "recommend me a printer"-type questions are not a good fit for this site. The help center has some information on what types of questions we are looking for.

Which printer for a beginner depends far more on the beginner in question than the various printers available.

If you are comfortable assembling parts and figuring things out a number of options exist.
If you need a fully-built object, a number of options exist.
If you require lots of dedicated support, via phone or email, there
are options.
If you can ask questions in a forum and get the answers you need (or
figure things out when you don't and post your answers for others to
find) there are options.

If you have special/esoteric printing needs, that puts constraints on - if you kinda vaguely want a 3-D plastic printer, but don't really know what you want to use it for the field is wide open.

Im comfortable with assembling things, especially from an instructions manual. Ive assembled ikea furniture before, so im comfortable with electronics lol. I like to build quadcopters and found that a 3d printer would possibly come in handy for parts. I can also follow instructions and tutorials. I would like something that i can download thingiverse files to and print out for me. And possibly in the future something that i can create something with cad (or other types of 3d printing software) and then print

So, narrow it down more - how big are your parts likely to be, or what's the largest part you can envision needing to print? Multiply that by a fudge factor,  see where it leads you. Think about things you might or might not want such as multiple extruders, how important speed is to you, whether you can trade accuracy for speed, the size of your piggy bank, and generally the many reasons this fits the "too broad" closure rule at present, and narrow them down, or ask specific questions about them.

The first item i would like to print is the following... https://www.thingiverse.com/thing:1823552

I would probably prefer quality over speed but i obviously dont want a 3d printer constantly running for a week

A budget would make answering your question alot easier. Do you have any experience with cad/cam software? What are you wanting to do with it? There are many inexpensive 3d printers but your skill level in mechanics/machinery, electronics, programming etc will also help others choose a good option for you. For example, plug and play units are usually more expensive than build your own models. But if you don't have the skill to assemble it the savings wasn't worth it

Hi Warren, thanks for getting back to me, id say £400 at the maximum for my first machine. I dont have much experience with cad but do work with others who use it so they could probably show me a few things. I use electronics in the work industry that im in and also programming so not much trouble there. And im not shy when it comes to building things so assembly shouldnt be a problem.

This is not an answer to the question. If you want to request clarification from the person who asked the question, you should post a comment - answers are reserved for, well, answers. You will be able to post comments once you achieve 100 reputation.

Oops, sorry....

Short answer:
Anet A8 in Ebay will be probably a kit "do it yourself". Something not easy for starters.
I suggest you buy a cheap and ready to use one. A rebrand of Malyan M200 (Monoprice select mini in U.S., Prima Creator in Europe) or something similar.
Long answer:
To select a printer take into account:

your experience in 3d printing
your experience in electronics and software.
your objective: learning, home user, professional?
if it will be used by children.
your budget
the kind of materials you plan to use: PLA only, mainly PLA and ABS, others. PLA only printers are usually a few cheaper because they do not have heat bed.
availability of support: official support, community size, market penetration.
build volume

Taken into account previous criteria:

Anet A8 is usually a Prusa diy kit. As all these kits, it is more
suitable when there are experience in 3d and hardware/software.
If the answer to previous questions is "no experience, home user, adults and childrens, medium badget, PLA&ABS, good support, small volume", a printer as Malyan M200 can be a good choice.
A printer as Flashforge finder differs respect to the previous that it has no heated bed. That means it is more suitable for PLA only.
(addition of more cases is welcome)

NOTE: This answer is a community wiki to promote multiple editions.


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Help preventing warping while 3d printing with polypropylene
I am wondering if anyone can help me achieve a good 3d print using polypropylene. I am trying to print custom insoles for shoes and I'm getting some bad warping/lifting (see image).

Some details about the print and process:

I have a Prusa i3 Mk2S with a Flexion extruder
I am using what I believe is a good quality filament (Verbatim PP): https://www.verbatim.com.au/3d-printing/pp-filament/3d-pp-filament.html
I am coating my hotbead with clear packaging adhesive (OPP tape) as per the manufacturers instructions. This appears to help quite a bit.
Bed heated to 75 degrees. I tried 100 but got hit with the "Heatbed Thermal Runaway" error which I believe indicates that not enough voltage is getting to the bed heater.
I've tried printing at 220 degrees and 170 degrees.
I've tried enclosing the printer in a makeshift enclosure to reduce the speed that the material is cooling at.
Other settings: speed 40mm/s constant, 0.2mm layer height, 20% infill, 3 top bottom and side layers.

The print takes about 5 hours and seems to stay down for an hour or two before starting to warp.
Does anyone have any suggestions of things I should try?

There is a good answer to the similar question that explains a lot: https://3dprinting.stackexchange.com/questions/938/what-are-the-ideal-print-conditions-for-polypropylene

Try heating your enclosure to 50C, as well as adding a brim.

Thanks Davo, I don't have a proper enclosure and the makeshift one that I made enclosed the circuit board as well... I'm a bit worried about the circuit board and components being at 50C. Do you think this might cause a problem?

I can't speak for your equipment. My equipment is rated to run at 55C with no issues. See what the manufacturer says.

You should enable the "brim" functionality of your slicer. This adds additional perimeters to the first layer, expanding the base of the model. The larger surface area gives more adhesion.

Thanks Tom, unfortunately this didn't really help for me. I have used a brim for ABS in the past and it has worked well but it wasn't helpful for PP.

One thing that seemed to help is making sure the heated bed was 100C. I was able to do this on my Prusa by turning off the front fan (for the whole print). If I have both the fan on and the heated bed at 100C I get the "Heatbed Thermal Runaway" error.
This produced a print that was better but still a bit warped.


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Is B-REP a ready to print mesh
before a mesh can be printed it needs to be 'repaired'. According to most tutorials that is including making the shape close and removing inner shapes. Reading through B-REP in Wikipedia there is no layman term or explanation how it differs form the traditional polygonal mesh create for example from scanning or exporting from CAD. Is B-REP a mesh that only represents a boundary and therefore ready to be printed?

a) about

Is B-REP a mesh that only represents a boundary [..] ?

B-Rep contains more information, see here:

There are two types of information in a B-rep: topological and
  geometric. Topological information provide the relationships among
  vertices, edges and faces similar to that used in a wireframe model.
  In addition to connectivity, topological information also include
  orientation of edges and faces. Geometric information are usually
  equations of the edges and faces.

b) about

and therefore ready to be printed

it is need not only check that the model is correct (no lack of a face, no wrong face normals, ...) but also that is valid for a 3d printer (no "floating" parts, addition of supports, ...).
Finally, recall the model is not what drives the printer, the printer is controlled by the machine instructions, usually gcode. Thus, the usual evolution is: parts description (.scad, ...), model format (.stl, ...) and machine instructions (.gcode).


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Graphite self-lubricating bushings performance?
I'm about to start building a CoreXY style printer and can't decide which bearings/bushings to buy. My first printer was a Delta with belts and opendbuilds wheels, so I'm lost regarding this matter.
Anyone tried these self-lubricating graphite bushings?
How do they perform compared to the standard LMUU bearings?
Robotdigg link
Aliexpress link

Do they run smoother, more silent?
Do they have play?
Do they stall after a while? Need maintenance?
Any feedback is much appreciated.

Bushings will be quieter than linear ball bearings.  Some online discussions complain of the linear bearings becoming noisy, and (in what I think is a failure of the balls to circulate properly) for the balls to develop flat spots.  If the balls aren't moving properly, you will end up with a bushing.  You might start with a bushing in the first place.
Bushings spread the load over the surface of the rods, so there should be minimal wear.  Bearings and bushings are limited by the load and the speed.  In 3D printers, neither the speeds or the loads are particularly high.  Bushings should work well.
Bushings may have slightly higher sliding friction, which could result in slower maximum printing speed for motors with the same torque.  The characteristics should be more stable as they age.
Others may have different experience, but I would consider either the self-lubricated brass bushings, or perhaps the self-lubricated graphite bushings.
As an example, inkjet and laser printers do not use ball bearings for the carrier.  15 years ago, it was bronze bushing on stainless steel shafts.  Over time, it has evolved to PTFE pads sliding on stamped sheet metal.


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Stringy PETG prints
I have started printing with PETG so I can create objects that won't deform if I leave them in my car.
My first prints look good, but have strings of material coming off the print in places.
What should I try to prevent that?
I haven't had this problem with PLA.

Can you attach an image?

I know PETG by nature strings a bit.  You may want to increase the temperature in the room, or add an enclosure.  I think when the hot end pulls away from the piece, the material is instantly hardening causing the stringiness, maybe increasing the environmental temperature will allow the filament to release from the work piece before it hardens into a stringy mess.

Would turning off the fan that cools the filament (not the print head) accomplish the same goal of slowing down the hardening of the PETG?

I've had similar experiences switching from PLA to PETG, and haven't gotten it fully figured out yet.
From what I know so far, to reduce petg strings:

Increase retraction
Lower temperature

Thank you for your input.  I spoke to a friend at work, and he said that he saw online somewhere that what you need to do is to adjust your temperature until you can just push through the filament by hand.  He got good results printing at 250, whereas I was at 240 on a printer similar to mine.  However, he also said that the exact temperature varies from printer to printer and also each spool of PETG may be different.

That sounds like good advice to me, thanks for sharing it!

If you are using a printer that runs Marlin, you might consider upgrading to a version with Linear Advance. Once I started using Linear Advance, I reduced the stringing of PETG.
Also I was able to reduce the retraction amount without reducing the quality of the prints.

Thank you.  How do I tell if my printer runs Marlin?

well , what printer do you have ?

Keep in mind that Linear Advance was added this year in the Marlin firmware .
I also did a temperature tower print , and ended up lowering by 10 degrees the print temperature. You can start by doing that , before you start changing the firmware on the printer :)


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Single point Z-correction after 3-point auto-leveling
On my Monoprice Delta Mini, auto-leveling is performed based on three pushbuttons, on which the printer platform rests: The nozzle moves downwards until one of the buttons detects being pushed down. Using the G29 G-code, this is performed automatically at three points close to the locations of these sensor buttons.
However, even after this calibration, the printer expects the platform at one of the test points to be lower than it actually is. Thus, when printing close to the front right sensor button, the printer "smears" the plastic onto the platform. At the other locations, the printing works fine. Therefore, I cannot simply adjust the overall Z-distance. (Multi-point auto-leveling gives even worse results since the platform tilts during the probing.)
Is there a G-code-based option to modify the Z-height of just one of the calibration points of the auto-leveling?
Edit: The bad leveling seems to be a common problem of this printer:
https://www.reddit.com/r/mpminidelta/comments/73xcxg/leveling_doesnt_seem_right/
https://www.reddit.com/r/mpminidelta/comments/6tqe7f/follow_up_on_bed_leveling_issue/
Till now, nobody seems to have a solution.

There is no "standard" g-code, especially for the auxiliary functions of calibration, and even more so for the calibration of delta-class printers.  I find that the Reprap Wiki includes a fairly comprehensive list: http://reprap.org/wiki/RepRap_Firmware_G-Codes and http://reprap.org/wiki/G-code.  These lists address the RepRap firmware, although they include some g-code functions which are specific to other types of applications.
If the Monoprice Delta firmware is based on the RepRap firmware, the lists might be helpful, although detailed documention from Monoprice would be the best reference.
Assuming there is no available or known g-code to adjust this, you work from the hypothesis that your three switches are not responding identically.  If possible, use a micrometer to measure the difference between the "idle" position of the bed and the point where the switch actuates.  It could be that the front switch requires more travel before actuation, which would then cause the leveling calculation to have a lower point for the front switch.  In the alternative to measuring, it may be possible to exchange the front switch with a rear/side switch and see if the problem moves.
Delta machines are more difficult to calibrate because everything interacts.  The three actuator delta machine is a simplification of a more complex 6-axis Stewart platform.  As I see it, a delta machine is a 6-actuator machine in which pairs of actuators operate "identically", except that minor variations cause unexpected positioning errors.  Sometimes these are modeled as a bowl shape with positive or negative curvature, although measurements I've made on my home-brew delta show an error that looks more like a carpet in a high wind.  Some factors improve the design, such as longer actuator arm pairs and smaller build diameter, which may help you with the Monoprice.


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Heated Bed vs Heated enclosure for large scale printer
I'm /relatively/ new to 3d printing (I'm getting pretty good prints from my Wanhao di3 plus, but haven't done any DIY kits or anything) and materials engineering is probably the furthest thing from my area of expertise so I thought I would pose this to more experienced makers:
If I'm building a large scale printer (probably a similar size to substation33 - sub33D's 1200x1200 printer) that I'm only going to print in PLA and MAYBE ABS occasionally, can I substitute the heated bed for simply heating the entire enclosure?
The idea would be to have a thermistor measuring the ambient air temp inside the enclosure with a heat gun or two to hear the entire enclosure as necessary. I want to do this to try and reduce the cost (significantly as far as I can tell) as it seems 400*400 silicone heat pads tend to go for about 80 bucks a pop.
An alternate idea I had was to use two or three heat pads and space them evenly under a glass bed, although I feel that this won't work as well because the heating won't be homogenous...
Any input is appreciated :)

I tend to agree with Davo, that you might want both. But I'd probably try the enclosure first. My printer is about 1200 by 400. I looked at options, and found some difficult trade-offs:
First, the big heatbed approach:

as you know, getting a single heatbed that big will be expensive (and if it ever breaks or fails, you have to replace it all).
a big heatbed also draws far more power than a RAMPS board can switch, so you'll have to use the on-board control to control a power relay (solid state or mechanical).
a big heatbed will also waste a great deal of power when you're doing small things.

Second, the heated enclosure approach:

more costly to heat up at the beginning, but if insulated it may be cheaper for long prints (with a bed that large, your prints might take really long, too) because it can retain the heat better.
if you keep the air circulating inside, you'll get much more uniform heat, rather than hot first layers and cooler higher layers.
consider the effect of the heat on all the other components: motors, electronics, pre-heating the fibers, thinning any lubricants,....
you could save some heating cost and time by providing a way to shrink the space to be heated: perhaps just a partition you can insert when doing smaller prints. It wouldn't have to be nearly airtight to make a big difference.

A third option is several small heatbeds:

this lets you turn on just the ones you need for any given print
still expensive, but cheaper than one big one, especially when any of them fails.
there will be uneven heat at the seams, but if you place the boards tight together I doubt it's enough to matter. You could also carefully trim the boards' edges to get the spacing closer to uniform.
temperature regulation will be tricky. If you want to support a temperature sensor for each board, you'll have to start hacking at the control software, because (as far as I can tell) there's no provision for multiple heaters. Probably easier to create a completely separate unit with a big power supply, and a simple thermostat for each of the beds, that you just set manually before starting a print.

Overall, I think the heated enclosure may be best. I like the hair dryer idea or heat gun idea, of course you'll need a little extra circuitry to switch it, but you can use the usual software for temperature regulation by installing thermistor or thermocouple in the case (just be careful about circulating the air well enough to avoid "hot spots").
You may want to add an extra cutoff to protect against runaway heating -- I had that happen once when a thermistor literally fell out of the mounting hole in the hotend. Something like https://www.grainger.com/product/SUPCO-Thermostat-407L11.
Let us know how it turns out.

If an aluminum plate is used for the third option. Shouldn't this even out the heat?

With a well-insulated and well distributed (or perhaps well-mixed is a better term - even heating) enclosure you should have a veritable heated bed by dint of heating the enclosure (with the bed in it), unless the bed needs to be hotter than the enclosure. I think that would be  bit more elaborate than "a couple of heat guns" and involve several fans to distribute and mix air continuously.
But - heated enclosures are not a freebie - everything inside the heated enclosure needs to be happy running at the sort of temperatures the enclosure is running at, and that can be hard on some electronic parts, shortening their lifetimes at least. Likewise, your calibration needs to be done on the hot enclosure - mechanical parts (particularly on a large scale printer) will change size due to the temperature.
Insulation will both reduce your running cost (the more heat you keep, the less you have to add) and help keep the temperatures even, by slowing the cooling at the edges of the enclosure.

If you want to print ABS at even one third of that scale, you will want a heated bed and a heated enclosure. Posts here (and my personal experience) support this; unfortunately, I can't find an impartial, non-anecdotal source to cite.

I think the commercial (stratasys) FDM printers have only a heated enclosure. The bed is plastic. However, the enclosure is heated to a fairly high temperature.

The point of using a heated bed it's to keep the part within a certain range of temperature while printing.
So, it's all about thermodynamic. It will be easier to keep the part at the desired temperature if the contact surface with the hot environment is larger, so, it might reduce warping and other related problems.
Anyway, it might be enough to have just the heated bed in contact with the part and not the whole environment to reduce the problems of abs printing.
You can check Tom3D's post, 3D printing with ABS: Hotter nozzle or hotter ambient? #Filaween, and video, YouTube - 3D printing with ABS: Hotter nozzle or hotter ambient? #Filaween, it might help you choose what to do.

So, can you get away with not having a heated bed and have (only) a heated enclosure instead? That's what the question is. I think you answered the opposite question.

I just read my answer again and it feels dumb right now. Using a heated gun might work, but it will have a weird heat distribution on the case. There will be really hot spots and hot spots, so, might work but not sure at all... Anyway, the key point of the heated bed it's to keep the part hot, so... it might work

The Stratasys Uprint is a professional ABS 3D printer and it does not use a heated bed. If you get the enclosure hot enough it should not matter if you have a heated bed.

This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review

From the manufacturer's support page, the UPrint has build a area of 8 x 8 x 6 inch (203 x 203 x 152 mm), which is a lot less than the OP's desired 1200x1200 mm. This means that the OP's printer would have a much larger enclosed volume to control and maintain the temperature of, along with the associated difficulties in doing so - it may not be as simple as just "scaling up". Also, the UPrint is ABS and the OP wants to predominately print using PLA. I'm not sure how useful this answer is & how it could be applied to the question.

If you could [edit] your answer and expand upon how to get the large volume to a steady and uniform temperature then that would be most useful. If you have experience with the Stratasys printers, you could provide a useful insight to how they operate. Otherwise, your answer is (more or less) just reiterating Tom's comment from a few years ago.

If it is yours first DIY 3D printer try building smaller version first with just one silicone heat pad. 400x400 mm is good enough.
From my experience:

I used 500 W silicon heater with SSR (AC mains) and it heats as fast as hotend (on DC 12 V).

I also recommend tooling plate (CNC machined Aluminum plate), it is better for heat transmission (Al) and it is more flat (machined to +-50 µm).

You might consider thermal insulation under the silicone heater and also some foil on build plate itself - to minimize thermal losses. Cork might be useful for bottom. For top I use blue foil (in which it was originally wrapped).

Enclosure I think it is also necessary, combined with heater, but then you must also have tubes for cooling of printed part, motors, fridge on hot end, etc.
Word of caution:
You must realize that you will be probably using 1.0mm nozzle or even more, since on 1200x1200 mm you will just wait for weeks for part to complete.
For reference: I print on 340 mm diameter (delta) with 0.3 mm nozzle and works just fine. But if I use just 0.1 mm instead of 0.2 mm layers it takes more time, but at the end it looks fantastic. So in your case even layer height must be big to reduce printing time. So you can increase speed, but then there could emerge some artifacts on printed object and also consider heater on hot end, which might be lagging behind.
There are a lot of problems when you go this big and all are not even closely to be considered solved, but if you have time..

This doesn't answer the question, which asks whether you can get away with not using a heated bed at all and substitute just heating the enclosure. This is good general advice, but I think it would be better to just stick to answering the main question.


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Weird ripping and warping of ABS print
I print my ABS at:

240 °C;
with a bedtemp of 80 °C;
5 % rectilinear infill;
0.25 mm layer height;
2 solid layers top and bottom;
Fan is completely disabled;
0.25 mm extrusion width;
50 mm/s perimeter print speed;
60 mm/s infill speed;
20 mm/s top solid and solid speed;
No acceleration.

When printing ABS, I place  an aluminum foil lined cardboard box over my printer to help keep the ambient temps up for less warping and stronger prints. I've never actually measured the temperature inside, but the cardboard box insulates very well.
I get this weird kind of tearing in my prints, I'm not sure if it's from too large of gaps in my infill, too fast print speeds, or not enough top layers.

Another guess is some kind of drooping because of the high ambient temps.
The tearing only occurs on large top layer surfaces.

Looking at the infill pattern visible through the tears in the top layer, it looks as if you have unreliable extrusion on the infill layers also.
The solid fill layer is lifted and torn, so it is unlikely that one or two more layers of solid fill will make the result better.  In my experience, bumps lead to taller bumps and print failure.
These diagnostic steps have helped me:

Print a 3 layer solid fill version, the top surface should be smooth and free of bumps;
Print a single layer version, it should be smooth, well attached to the print bed, of even thickness, and a good surface for the next layer.

Given your results, I am suspicious that you may have one of these problems, which I've listed in the order of likelihood:

Partially blocked nozzle
Excessive drag from the filament supply, such as a spool with crossed filament which jams itself, preventing unwrapping;
Extruder feed roller slipping (perhaps full of dust), often a side effect of 1 and 2;
G-code error dropping the temperature;
Bad heater or thermistor, perhaps intermittent short of the thermistor, causing under heating even though the "average" indicated temperature is correct.

Printing gliders is a cool application. It shows off the weight advantage extrusion 3-D printing can deliver.  Nice.

I think I need to clean out my extruder. I've been getting weird waves in the lines I've been printing, suggesting some sort of non-uniform extrusion rate. This could also have led to bumps and some things causing the ripping and bubbling.

I believe it is from the ABS falling into the gaps of your 10% infill. I print ABS with 35% honeycomb infill and I use five or more solid top layers at 240°C. Fewer, and it sags into (or exposes) the infill layers.
I recommend more top layers and a higher infill percentage.
I also recommend starting the cooling fan at 50% capacity or more, before starting the first solid top layer.

Ok thanks, I'll try 20% infill this time and 3 top layers, I'm trying to print a glider so it needs to be as lightweight as possible.

You can reduce infill line width along with infill line spacing to keep same mass but avoid wide gaps for top layers to sag into.

This looks a bit like you may have a level issue with your printer. I've had similar results when my nozzle isn't clean and my bed is slightly off level. When the nozzle isn't clean (inside and out) either the flow rate out is different than what you set it to be due to back pressure or there is material on the nozzle causing the nozzle to drag through the molten plastic.
I also use a lower nozzle temperature, around 220-230°C. Printing with 10% infill is my standard setting with two shell layers, honeycomb fill or diamond fill.

I found that infil of 15% and another top layer fixed my problem.

First of all, don't specify the extrusion width, the slicing software does the calculation for the optimal value by itself: if you watch this video about extrusion width and you cross the data with this tweet you will see that the standard value is already optimal.
Second, if you put the printer in a box for insulation you should redo the temperature calibration tower to find out which temperature produces the best results.
Once you do both you'll find the problem will disappear.