text:
Will I see a noticeable difference switching from a .4mm to a .3mm nozzle?
I currently print with a .4mm nozzle on my extruder, and my prints seem to come out fairly accurate; would I see much of a difference if I went to a .3mm?
What are the pros and cons of larger and smaller nozzle sizes?

1) Smaller nozzle advantage: sharper "corners" (higher X and Y resolution)
2) Larger nozzle advantage: faster 3d printing (because you can print the shell faster as each perimeter can be thicker so you'll need less perimeters to be printed to get the same shell thickness. Same true for infill).
3) Smaller nozzle disadvantage (varies, debatable): higher risk of clogging. There are of course other factors which can result in clogging, but this can also affect it as even finer particles in less quality filament can get stuck now.
4) Smallel nozzle disadvantage: since less plastic can come out at a given duration of time, it means less speedy printing of larger layer heights, if at all possible.
I feel like I should get back to (1) and explain why it is so.
When companies market their 3d printer they usually talk about the layer height (the Z resolution) completely ignoring the X and Y. This makes sense for marketing. Luckily it is not hard to explain what is usually left out and what is important for one of the answers to your question on what are advantages of smaller nozzles:
The Z resolution depends on two main things:
1) The stepper motor driver accuracy of your 3d printer's motherboard. Pretty much all are the same now. Claiming your 3d printer can print at 20 micron layer height doesn't say anything, pretty much any 3d printed today can.
2) Nozzle/extruder quality, nozzle diameter. The latter surprisingly does not determine much. Because of how FFF/FMD 3d printing works, the perimeters of your 3d print can be way thinner than your nozzle diameter. This might sound odd but there's a simple explanation: the molten plastic coming out of the hotend is squished and stretched when the head moves. Because it is stretched, it can be made thinner as you increase how much it is squished. There's not much experimentation done on this and available online, only from personal experience I can say I can print perimeters 50% thinner than my 3mm nozzle. So I suppose if you wanted thinner perimeters than that, you would need to swap to a thinner nozzle.
Why would you want thinner perimeters? To get sharper corners or in other words better X and Y resolution for your 3d prints which is ignored by most unlike the overstated "layer height" (Z resolution).
Here's an illustration to help you visualize how fatter perimeters and less sharp corners/edges on your 3d model result in "lower X/Y resolution" (the illustration is a 2d cutout, viewed from the top):

Great answer! I might also make a note that thinner widths can lead to poor adhesion, which can lead to warping in most filaments.

Thanks. But I'm not sure about that. The theory makes sense but I haven't experienced it myself. I might add it with a "maybe" or "might", will that work?

My understanding is that the only difference is your range that your layer height can be. For example, the optimal layer heights for a 0.4mm nozzle fall between 0.1-0.3mm. So, we can assume a smaller nozzle will yield a lower range. Keep in mind that varying sizes in the nozzle could produce complications more prominently than with a standard size. Things such as ooze, clogging, and filament backup may occur with a smaller nozzle size if your slicing engine is not setup correctly.


text:
How thin can my extrusion be from a 1.2mm extruder?
I always assumed that the smallest diameter that you could extrude was equal to the diameter of the extruder tip itself. Recently I heard that you can actually extrude a line that's as little as half the width of the nozzle opening.
Is that true in theory? In practice?
My printer's 0.3mm nozzle broke recently, and the only replacement on hand was a 1.2mm nozzle. The prints have been fast, but really coarse and imprecise. I've dialed the extrusion diameter down from about 2mm to 1.2mm for some smaller, more intricate parts, and it worked fine. Can I go down to 0.9mm or 0.6mm extrusion diameter without it screwing up my prints?
If I can't do that, what does happen if I try to print 0.6mm out of a 1.2mm extruder nozzle?
For this question, let's assume an FDM printer using PLA and/or ABS filament.

All I can comment on is the minimum limit will depend on the physical and chemical properties of the  plastic, nothing more.

I gave it a try on a few prints over the weekend. I had both successful and unsuccessful prints. It can work, and certainly working with a 1.2mm nozzle (huge!) reducing down to 0.6mm or even 0.9mm allowed a significant improvement in the amount of detail and the sharpness of corners in the resulting prints. I reduce the layer height down to 0.2mm, too, which I imagine helped.

The main issue with very narrow extrusion widths (less than the nozzle size) is that you get really poor "nozzle squash." The plastic isn't pressed down very hard as it's extruded. That causes poor layer bonding and weaker prints.
The flow of molten plastic coming out of the nozzle must be drawn down by tension in order to end up smaller than the nozzle opening, and that drawing effect makes it difficult to get good contact with the previous layer. So you end up with a "stack of logs" structure kind of like this:

(This photo actually shows layer height = extrusion width = nozzle size, which is another no-no, but the end result is similar.)
What you want instead is something very "mashed together" and strong like this:

How finely the the strand can draw down -- versus smearing or breaking apart into blobs -- will depend greatly on the type of filament and the printing conditions. For example, nylon draws down extremely well because it experiences a large degree of strain crystallization, and actually gets stronger and stiffer as it's stretched. PLA tends to get more brittle when strained and may break into stringy blobs. ABS doesn't change terribly much because it's highly amorphous. Polymer type, blending agents, print speed, printing temperature, and cooling will control the drawing behavior of the filament.
Another factor to consider is what the strand spacing is within the print. If you set the extrusion width equal to half the nozzle width, depending on the slicer, adjacent strands may be placed with pitch equal or slightly less than half the nozzle width. So after the first strand is printed (say an unimportant inner perimeter) the next strand will be printed with the nozzle partially overlapping the previous strand. This effectively creates a constriction to force the plastic out of a smaller opening to one side of the nozzle, which is not too different from printing with a smaller nozzle. Subsequent perimeter strands may then tend to "heal up" even if the first is low quality. This effect doesn't completely fix the problem, but it helps account for why under-width strands seem to work better than they ought to.
Of course, even if the strands turn out ok, it's arguable whether there is any benefit. If the goal of a smaller extrusion width is more precision and sharper corners, you may not actually accomplish that goal. When the filament is being drawn down by tension in the cooling polymer, it may tend to "cut corners" and get pulled into a rounded arc when the nozzle changes direction. That may defeat the point of using a thinner extrusion width in the first place. Generally I only recommend using under-width strands to capture thin-wall detail that is only a little bit too thin for the nozzle, not as a way to improve overall print quality.
In comparison, having the extrusion width equal or wider than the nozzle ensures the plastic is firmly squished downward into intimate contact with the lower layer. You can fudge this a bit and still get decent results, but it's usually best to keep the extrusion width equal or larger than the nozzle size. There's no hard cutoff where it will / won't work.

Very informative answer , but I'll have to respectfully disagree from personal experience. That is, the bounding doesn't seem poor to me which is a premise you made to explain some of the potential issues.

It's hard to objectively determine layer bonding strength without a force tester unit. Performance will vary wildly with settings and materials. For example, Stratasys has some patents on deliberately leaving the nozzle a fair distance above the print and letting the drawn-out strand gently fall onto the previous layer, so they must think it's viable in some cases. (The patents are concerned with techniques of making corners sharp and specific nozzle geometries that prevent material build-up when doing this.)

In other words, your mileage may vary?

Yep. Too many factors to really make concrete predictions. Even which slicer you use. For example, Slic3r assumes the strand has a flattened oval cross-section, so its extrusion volume calculations can go off kilter when your extrusion width is less than [layer height + nozzle size] because that's the minimum size to fully develop a symmetrical oval shape strand.

source: Stack Exchange

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

sort: votes


text:
Why does my MKS Base not recognize my thermistors?
I recently upgraded my Geeetech Acrylic Prusa i3 with a MKS Base V1.4 and it would not recognize the thermistors (100K {type 1}) even though they worked fine with the Arduino Mega 2560 with the RAMPS shield.
After changing the thermistors for the 4th time it began to work, but the model printed was quite distorted. Then without warning it suddenly does not recognize them again. The board does create the USB port, but does not appear to communicate with my computer.
Is the problem more associative with the board or my computer?

Does the one that stopped getting recognized, still get recognized by the arduino?

What exactly means "{type 1}". And did you alter your firmware?

@EricJohnson It was both thermistors that stopped being recognized. If there is another way of determining whether the Arduino recognizes them other than through the computer (Repetier Host) I am unaware of it.

@amra Arduino configuration.h lists thermistors/thermocouple by type, and there are a large number listed there, my particular thermistor is a 100K type 1 on that list.

I see. My assumption was that you have wrong configuration in your firmware. Did you try another SW instead of Repetier Host, e.g. Pronterface?

@amra yes I did as a matter fact I used two versions of repetier and Pronterface to no avail. What confuses me the most is that it worked for a short time then just quit again. I have reset the board and attempted to reload the Marlin firmware but it will not reload, even though it does set up the USB com port. Thank you for your interest and help.

I would verify if your board is working fine. Could you measure voltage on  the thermistor? It should be around 5V (it was 4.79V on my RAMPS board). And about the change to Marlin firmware - did you use Arduino IDE for the upload? If yes, then what was the error?

@amra The voltage across both pins on the board is 4.95 on the 20v dc scale, and the resistance is 102. or above on the 200 volt scale. Yet the thermistor reading on my computer remains at 00.0 for both thermistors., and no other components are functional (motors, endstops). Thanks for the effort.

@amra By the way I worked on the Matlin firmware until I got no errors, only a white reading of the upload particulars.

Here are good videos about configuring marlin firmware: https://www.youtube.com/watch?v=2RbcMvhatjU  and  https://www.youtube.com/watch?v=In93vVd1WDQ

@BYE Did Marlin firmware help with the thermister?

@amra no it did not I am pretty sure I received a defective board. thanks for the  help and the references. Sorry to be late replying internet router has been down.

You should:

Ensure that firmware has proper thermistor configuration. For details see this video tutorial.
Verify that your thermistor works properly. Measure voltage on it. It should be around 5V on this particular board.
There is possibility that the board is defective. Replace it.

Temperature sensor possibilities for Marlin firmware:
// -2 is thermocouple with MAX6675 (only for sensor 0)
// -1 is thermocouple with AD595
// 0 is not used
// 1 is 100k thermistor - best choice for EPCOS 100k (4.7k pullup)
// 2 is 200k thermistor - ATC Semitec 204GT-2 (4.7k pullup)
// 3 is Mendel-parts thermistor (4.7k pullup)
// 4 is 10k thermistor !! do not use it for a hotend. It gives bad resolution at high temp. !!
// 5 is 100K thermistor - ATC Semitec 104GT-2 (Used in ParCan & J-Head) (4.7k pullup)
// 6 is 100k EPCOS - Not as accurate as table 1 (created using a fluke thermocouple) (4.7k pullup)
// 7 is 100k Honeywell thermistor 135-104LAG-J01 (4.7k pullup)
// 71 is 100k Honeywell thermistor 135-104LAF-J01 (4.7k pullup)
// 8 is 100k 0603 SMD Vishay NTCS0603E3104FXT (4.7k pullup)
// 9 is 100k GE Sensing AL03006-58.2K-97-G1 (4.7k pullup)
// 10 is 100k RS thermistor 198-961 (4.7k pullup)
// 11 is 100k beta 3950 1% thermistor (4.7k pullup)
// 12 is 100k 0603 SMD Vishay NTCS0603E3104FXT (4.7k pullup) (calibrated for Makibox hot bed)
// 13 is 100k Hisens 3950  1% up to 300°C for hotend "Simple ONE " & "Hotend "All In ONE"
// 20 is the PT100 circuit found in the Ultimainboard V2.x
// 60 is 100k Maker's Tool Works Kapton Bed Thermistor beta=3950
//
//    1k ohm pullup tables - This is not normal, you would have to have changed out your 4.7k for 1k
//                          (but gives greater accuracy and more stable PID)
// 51 is 100k thermistor - EPCOS (1k pullup)
// 52 is 200k thermistor - ATC Semitec 204GT-2 (1k pullup)
// 55 is 100k thermistor - ATC Semitec 104GT-2 (Used in ParCan & J-Head) (1k pullup)
//
// 1047 is Pt1000 with 4k7 pullup
// 1010 is Pt1000 with 1k pullup (non standard)
// 147 is Pt100 with 4k7 pullup
// 110 is Pt100 with 1k pullup (non standard)

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


text:
What air filtration options exist for enclosures?
Given the emissions that 3d printing gives off (ABS = styrene and other chemicals, PLA give some off, etc), what options are there to filter the air in the enclosure other than venting the air out of a window?
More information on the chemicals 3d printing emit:

http://built-envi.com/portfolio/ultrafine-particle-emissions-from-3d-printers/

It looks like activated carbon filters would be a strong performer for ABS (styrene) and PLA (lactide):

https://www.sentryair.com/activated-carbon-filter.htm

Are there better filtering materials or processes for filtering the air in an enclosure?
Here's an example filter setup:

This fan mount: https://www.thingiverse.com/thing:780001
60mm fans and this filter: https://www.amazon.com/gp/product/B00XNI5SY4
And sandwich the filter on the fan using this fan grill: https://www.thingiverse.com/thing:11906

Do you mean a system for pumping air out of the enclosure that stops particles from leaving the printer and getting into the air in the room?

Can you please be more specific with your question and details? At the moment, your question is too broad.

Apologies!  I'll edit my question right now.  The question revolves around the emissions that printing can give off and how to filter the emissions out of the air.  As an example, printing in ABS emits styrene which is potentially carcinogenic.  So to filter the styrene out of the air, a fan can be added to the enclosure to pull the air out of the space and filter it.  Please let me know if you would like any other information to make this more clear.

Hello @Chase Westlye, I noticed your question has been up for a while now. Have any of the answers below been able to solve your question? If so, would you mind accepting the appropriate answer. If not, what is missing so that we may help you further? Also, if you have figured it out on your own, you can always answer and accept your own solution. Thank you.

I would try one of those cylindrical carbon filters that growers use, these are not that expensive so probably worth a try. Have been using those for apartment ventilation for some time now and they appear to be pretty good at removing smells.

My residential materials expert referred me to these links (3D Printing Fume Extraction Solutions, and ABS 3d Printer Nanoparticle and Chemical Exhaust Air Filter) and thinks that you're pretty much on track with the idea of using activated carbon.
We both primarily print with ABS with my Replicator Dual and what's worked enough for me (in the past 5 years) is to keep my printer next to a window or vent in my den at home. The window is obviously a good ventilation option, but the variability that it creates in the ambient temperature screwed with my prints. Later, I moved my machine into its own hutch, which, if it is an option, would greatly help the overall environment for both the machine and any stored filament.
We'll keep poking around, but hopefully that helps in the mean time.

It depends on how often you use your printer, meaning how many particles does your printer emit for time-unit. If you print nonstop with 5 printers then it's a different situation, opposite to one print per week.
Best material for passive filtering is carbon foam. It has the ability to capture chemical fumes. See this filter comparison.
Having an enclosure with such a filter would be a good start.
For example BuzzBox.

I have to say that I don't know the particle size of 3d printing emission and how good the filtering ability of carbon foam is.
A step above is to bind such an enclosure bundled with an air purifier.
The best option would be laboratory equipment. But it is the most expensive one. It is designed to filter toxic vapours, fumes, gases and particles.

Update
If you decide to build an enclosure on your own, take a look on Prusa's  video on a DIY version build from Ikea table. There is no filtration system, but it should be simple enough to integrate a carbon foam with a ventilation.

video: https://www.youtube.com/watch?v=oS7ZtBNh2hE
blog post: https://www.prusaprinters.org/cheap-simple-3d-printer-enclosure/
3d models: https://www.thingiverse.com/thing:2864118

Update:
Here is an article about DIY enclosures: https://all3dp.com/2/3d-printer-enclosure-5-cheap-diy-options/

I have looked into this a lot. Especially when I had a phd chem engineer girlfriend who kept talking about how the fumes might give me cancer.. Frankly the system you need just costs too much. Lab equipment can run 20k easily. Not to mention the noise. What you really need is a backyard shed, but as one who lives where it snows I understand that is rarely a realistic option.
The Buzzbox looks cool and there are other brands. However their prices are usually as much as a flashforge, and usually cannot even hold a flashforge.
More importantly there are parts where you can DIY your own.
300 for a plexiglass case that can only hold a mini printer is not good enough by far.
Take a product like this air scrubber Or build your own this like this hard core one designed for a laser cutter.
The local hackerspace should have a large laser cutter. Plastic should run 100 - 200 depending on how thick of a sheet you want. I personally buy scrap pieces. Designing a square box, adding hinges, then coating the edges with silicon sealant. Evacuate the chamber when done printing. Also should double as a heat chamber..
For me, I can easily run 5 printers at a time. So I might take a metal Cabinet, seal it up. test it with a fog machine. Cut out a hole for the evacuation hose, and wire up camera. But I am far from having that much free time.
Also if I manage to make it air tight it should reduce fire hazard.
Taking that laser cutting fume extractor. There is nothing that will perform better than that. I hear you might get some smell, but that was in regards to laser cutters.

I was very concerned about this issue when I bought my own 3d printer, so I decided to design fumes extraction solution for this. It is tailored only for my Zortrax M200 but I hope that it is good example of how to solve this problem with limited budget.
http://www.thingiverse.com/thing:1158639

I designed this self-printable filter enclosure.
Rather than vent any air outside the printer enclosure, this will recirculate the air within, constantly running the air through the filter while at the same time conserving the heat needed for ABS prints. It's simple, and you can employ more than one of these or, using my design files, extend the size of the cabinet to stack more layers of carbon filtration material.  It only employs one inexpensive PC fan to move air. I've found it effective for my purposes, never having to smell ABS prints or suffer eye irritation from them again.
https://www.thingiverse.com/thing:2209222

with what kind of enclosure do you combine this? Have you noticed a better print from circulating the air and thus equalizing the chamber temperature?

I built my own enclosure using plexiglass and some open-source mating pieces to assemble it, and sealed with clear tape.  So, any enclosure that would keep air from escaping should work.  As for recirculating the air and normalizing temps, I'm not sure that it makes that much difference.  The biggest thing was just having the enclosure to help with that.  Any air movement can cause cooling of the filament during a print, which can be desired or not desirable depending on the filament type and what you're printing.

Anybody consider using a Grow Box Fan and filter inside an enclosure.  They come cheap with 180 cfm fan and / carbon filters.

Seems like it would work well, just wondering if they are really noisy.

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/


text:
What is the benefit of the Arduino shield based electronics?
Some electronics come as a single PCB. They have CPU and everything on just one board.
Other electronics are a shield for an Arduino. So these are always two boards. The Arduino and the other PCB.
You probably don't want to exchange the Arduino unless it is broken. Does it break that often or are the two boards just the predecessors of the one board solution?
What are the benefits/downsides to having one/two boards?

For folks who do a lot with Arduino, shields/hats/wings/whatever are freshman-year parts, 80% solutions for low-experience makers who want to say "I built this line-follower/temp-logger/smartcam/printer/etc" after snapping together 2 parts and flashing the demo project code. Since any extra pins are typically blocked by the shield, they are not even very expandable or customizable. Most would be better off with a single board; turn-key code for noobs, and a slightly more complex than a plain uno board procedure for vets to code with C++.

Many 3d printer motherboards are based on Arduino/Atmega microcontroller and just add some stepper motor drivers, MOSFETs and such in a single board. That explains why you use the Arduino IDE to update or modify their firmware.
Now why you would want to use an Arduino + an Arduino shield board like RAMPS? Well if you're not good at electronics, are happy with the cost of your own board, don't care much about upgrades/modding beyond what is possible with your board, maybe you shouldn't, it might be overwhelming.
There are several advantages with using Arduino with a shield for your 3d printer, "two boards are not just the predecessors of the one board solution", no.
1) It is moddable/exandable/upgradable/has replacable parts.
If your printer came with its own motherboard that doesn't have additional or enough pins to add more fans, enclosure lights, a second extruder, an LCD and you want to, it sucks. RAMPS can do that, it has plenty of extra pins.
It is upgradable. You want to replace the stepper drivers with a new one? Or you accidentally damaged the one you have? Fear not, you can just replace that instead of the whole motherboard.
Think if it like other motherboards being PCs on which you can't change the CPU, RAM and GPU.
2) It is here for a long time, you will be able to acquire one for a long time.
There isn't just one company making RAMPS or similar sheilds. Sometimes 3d printing companies go out of business or stop producing your particular motherboard. RAMPS is likely here to stay. Because Arduino is very likely here to stay.
3) As said above, not just one company owns or makes RAMPS or other Arduino shields. Besides the possibility of your motherboard not being produced anymore, there's also the advantage of not being at the mercy of one companies pricing and shipping policies. This is true for some other boards as well though.
4) It is possibly cheaper than what have you. I don't want to post a link, but one company right now is selling their derivative of Printrboard for like $180. Check the cost of Arduino Mega, stepper drivers and a RAMPS board yourself, quite a difference. That said, there are some boards which are close in price.
5) It's an Arduino. Why is this a good thing by itself? Because many people who have a 3d printer are tinkerers/makers and they already use Arduino for other projects. It is open source with a rich library to control many things. The modding and upgrades for your 3d printer which can be done with Arduino is another level higher. Or it can be a good learning experience for your future Arduino projects. If on the other hand you already use Arduino and are experienced with it, you might use it just because you know how to control it/fix it better than some specialized board you haven't seen before. Plus for a guy like you your 3d printer's motherboard will be an "off-the-shelf" part, that's nice, right?
Video on RAMPS: https://www.youtube.com/watch?v=FYJn6FuWOv4

There isn't really a big advantage to one solution or the other. The approach of having separate boards means it is more modular and broken parts can be replaced more easily, but electronics don't break on their own: it is almost always user error. If you are even a tiny bit careful when assembling your electronics, you won't ever have anything break and the advantage of having modular electronics is moot. On the other hand, there's no disadvantage to using modular electronics either.
Of course, another advantage of modular electronics is that you can upgrade separate components (for instance, swap in better stepper drivers). The value of this advantage depends on whether you eventually want to upgrade.

Agree, although even the wisest of us do some stupid things sometimes. I've fried the some components on some PCBs (one being a Printrboard) just because I placed the probes of a voltmeter in the wrong locations. Also, from the answer it seems like you'll want to replace some components only when you damage them. But another case is when you want to upgrde them. Still, valid point.

If I look from a different angle. A single board having less modules, therefore needs less assembling and therefore smaller risk of accidentally breaking the electronics?

Nah. The assembling consist of just plugging a female socket to a male header or vice-versa. I have never heard of anyone breaking either when connecting them, they are sturdy. And you can't connect wrong component to the wrong place because their connectors are positioned physically differently, you can tell by just looking. As for the few power cables which have to be screwed in place, well if you're having trouble getting them right than like I said you don't know much about electronics and are better off with a single board controller.

There is an advantage to the one who builds the shield: They don't have to design the circuit that is on the Arduino (main board), possibly even including Wifi or USB communication. The components on board are more expensive in small volumes, so the ready made boards are even competitive in price. Developers get a proven and well known board, with perfect support in software toolchains. Depending on the solution, they might even have less trouble with certification, as the high frequency components are already known. So, they only have to design the shield, holding some motor controllers, sensors or similar.
This makes it possible to produce small amounts of units very fast, which is also a benefit for the end users / end customers. It makes niche solutions possible at lower cost. Being able (if at all) to swap out a single component is likely not a real benefit, except if you enjoy taking your electronics apart.


text:
Holes/ missing layers (after retraction) in 3d printed objects
My printed objects have horizontal holes in them (as seen I the picture below):

This doesn't only look bad it also makes the object break at the seems.
Looking carefully at the printing process I can see that after a retraction there's a small amount of time the hotend isn't extruding plastic.
Material: PLA, Printer Robo 3D R1+, Slicer: Cura

(answering my own question)
The problem was the extrusion distance settings in Cura's advanced tab, reducing the value to 1.5mm solved the problem.
Other problems with the same symptoms:

Partially blocked hotend nozzle.
Incorrectly configured steps per mm for the extruder motor - this youtube video shows how to test and configure this.


text:
Can MeshMixer export models for color 3D printing?
I have captured several models using 123D Catch and Autodesk ReCap 360.
I do all my "clean up" work in MeshMixer to prepare the models for printing, and while exporting to STL works great for printing on my home FDM printer I haven't been able to get color files exported.
I would like to export scanned models from MeshMixer and upload them to an online printing service (i.e. Shapeways or iMaterialise) and have them printed on high end color machines.
My current workflow goes as follows.

Export raw model (OBJ) from 123D Catch or ReCap.
Open model in MeshMixer v10.10.170.
Remove unnecessary parts of the model.
Export model as OBJ, OBJ with per vertex color, or VRML.
Zip model and exported texture files and upload to an online service.

The file in MeshMixer looks great, but ends up with either jumbled or nonexistent  textures when it's uploaded to an online service. I'm guessing I'm exporting the file wrong for 3D printing, or possibly that I need to do some post-export editing to make everything line up correctly.

Color is only displayed if you set MeshMixer to render VertexColor:
MM menue/View/MeshColorMode/VertexColor

Color should be visible if VertexColor is active.

Meshmixer is a sculpting program, so it isn’t made for taking exact
measurements, creating mechanical parts, or creating architecture
models.
Basic rendering options make pretty screenshots, but advanced users
might want to add in backgrounds or set up custom lighting.

Also, you can read more about this matter on this link.


text:
How to smooth the surface of parts printed with Co-polyester (PET) filament
Are there any techniques for getting a smooth finish for parts printed with co-polyester (PET) filaments? More specifically, I am looking for an alternative that does not roughen the look of the part - such as using sandpaper - but rather works like acetone baths for ABS.
In particular, I want to treat ColorFabb's XT filament made from the Eastman Amphora™ 3D polymer (datasheet). This is also the polymer is also used in:

ColorFabb nGen and XT
Taulman3D n-vent
TripTech Athiri 1800
3DXTech 3DXNano

Ethyl acetate (sold as a MEK substitute) is supposed to work for vapor smoothing PET.  It doesn't seem very toxic (it's used to decaffinate cofee and tea, and as a nail polish remover), but you might want to look more into it.  There's a post on Printed Solid's blog where he vapor smoothed colorFabb XT and MadeSolid PET+ along with a few other filaments and got some good results.
http://printedsolid.com/blogs/news/37035395-vapor-smoothing-3d-printed-parts-pla-colorfabb-xt-t-glase-pet
The links in the blog don't work for me, but google was able to find slightly larger versions:
https://cdn.shopify.com/s/files/1/0887/0138/files/blog_2014-03-20-18.38.04-1024x613.jpg?16147388421280943481
https://cdn.shopify.com/s/files/1/0887/0138/files/blog_2014-03-21-18.16.28-1024x612.jpg?9543779874607042697

This seems like fairly reasonable solution for PET. Thanks for sharing!

I've found a chart which covers several plastics and solvents and only two of them (Chloromethane and Chloroform) are rated "D" which includes dissolving the material and both seem to be quite nasty and I doubt you will be able to purchase them without being placed on several lists.
Is it possible that something like XTC-3D from Smooth-On would work for you?
Also some more information on dissolving PET here, several sources also mention PET is affected by Hydrogen Peroxide but they do not mention to what degree the plastic is affected.

Thanks for sharing some great resources! I will certainly not be experimenting with pure ozone or phosphorus any time soon, but some product like XTC-3D could potentially be of help. All in all, it seems like PET is a fairly stable plastic chemically. Thanks!


text:
Can a common 3D printer be used to print masks for PCBs which use SMD components?
Common 3D printers (read "cheap") may be used to print masks for PCBs (printed-circuit boards) which use PTH (through-hole) components.
But can they be used to print PCBs which use SMD components? I'd like to make boards at least for Arduino-like SMD chips.

I noticed that your question has a few answers available and has been open for a while, just curious if any of the available answers was able to help. If not, then what questions do you still have?

Both answers deal with printing the actual circuits, while the question is about printing masks on common PCBs which would then be corroded. Maybe I need to rephrase my question to make this clearer?

Yeah, that would help. I don't think you need to reword your question, but maybe just add that note. Also it looks like @TextGeek mentioned masking in a comment that might help.

Is there a reason you cannot use photoreactive copper boards and expose them to light with a printed transparency?  Desktop laser jet printers can usually print directly onto transparencies to generate photomasks.  These can produce quite detailed circuitry but you may need to check the specifics.

In addition to the thermal issues Tormod raised, there is a conductivity issue. Present conductive filaments are much less conductive than copper. The power loss may be enough to affect functionality. Also, the lost power goes to heat, making the thermal problems worse.
For bulk materials, "volume resistivity" is measured in "Ohm-cm", which is the resistance of a 1 cm cube of the material, measured from one entire face to the opposite entire face (see https://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity).
Copper has a volume resistivity of about 1.68 microOhm-cm.
Proto-pasta conductive PLA filament claims 15 ohm-cm (http://www.proto-pasta.com/pages/conductive-pla). Functionalize F-Electic™ claims 0.75 ohm-cm (http://functionalize.com/about/functionalize-f-electric-highly-conductive-filament/).
Printing itself significantly raises resistivity. Proto-pasta claims 30 ohm-cm along X and Y, 115 along Z. More intuitively, each cm of length of a 2.5mm wide printed trace, 0.4mm thick, should add several hundred ohms with the Proto-pasta, or several tens of ohms with the F-electric. That may be enough to matter.
It's probably worth mentioning that there's a specialized PCB printer (the "Voltera") that uses (pricey) conductive ink, and can also dispense solder paste: http://www.computerworld.com/article/2885188/3d-circuit-board-printer-a-smash-hit-on-kickstarter.html

I imagine pre-calculating the resistance of a printed conductor can be a science in itself, meaning it could be difficult to use protopasta for anything complicated!

@TormodHaugene, that's surely true. I just approximated by cross-sectional area and length, which should be in the ballpark. But layer height, ratio of nozzle to layer height, and many other things surely matter, too.

Question is about printing masks, not about printing circuits directly.  This is a good answer about printing circuits but not about printing masks.  -1

In theory, I imagine you can, but there are some practical considerations that might need some thought:
If you have a desktop printer with multiple extruders, you could probably print with both one conductive and one structural filament, and thereby build circuits in 3D.
One concern would be the low melting points of most 3D printed filaments, since one would have to limit the heat generated by the mounted components and connections so that the structure of the "board" would not be melted.
Mounting components to the board would also differ from a normal PCB, since you would have to connect the components with the conductive filament without melting the structure of the board. In other words, you probably would have to use conductive filament as "solder", and melt components into place.
Whether you could use typical tools used for mounting SMD components with conductive filament as solder is beyond my knowledge.

This is definitely an easy solution with either a multi-extruder and/or updated firmware/slicer that supports mid-print filament stops.

I do not intend to print the whole board from scratch with conductive filament, but to print a filament mask above a standard PCB. The mask would (if possible) allow corrosion of the PCB copper by standard PCB-making process, leaving the copper tracks where the masks protects them. I'm concerned about if the mask would stick and if it allows fine tracks needed for SMD components.

Ahh, sorry, hadn't realized that's what you meant. There's a report of someone using NinjaFlex filament as mask on standard PCBs, which says it adheres well to the copper, unlike some other filaments. http://3dprint.com/11367/3d-print-copper-circuit-board/ Or one could substitute a laser cutter for the extruder head, and subtract copper directly... :)


text:
How to achieve dimensional accuracy of printed parts?
When designing parts that should either fit with external objects or other printed parts, what measures can one take to ensure that the dimensions of the final print are accurate and fit the other object?
To my knowledge, you at least have two options to account for printer inaccuracy and shrinkage:

Adjust the space around joints in your CAD model
Adjust dimensional offsets in your slicer software

Are there any good workflows one can use to design and print 3D-models accurately without resorting to trial and error?

I think the best way to go about this would be to calibrate your printer and slicer as best you can.  One of my pet peeves is when people upload STLs that have been adjusted to fit their printer/material.  There are many suppliers of material that vary in quality as well as many materials and different printers that the tolerances shouldn't be built into the part because in the end it usually just makes it harder for others attempting to print the model.
If you aren't sharing models then all I can say is you are still better off to calibrate your printer and tune your slicer to your material.  You'll have more luck with models from other people and have an easier time designing your own.
If you still have trouble then modifying the model is probably the last option.  I don't know of any CAD programs that can work with problems 3D printers have so experience is going to be your only help.  I know in Inventor you can go around and Thicken/Offset individual surfaces of the model to compensate or if you had a percentage for your shrinkage you could get creative with formulas in the sketches.

So basically: set printer and filament settings in the slicer to achieve as accurate dimensions as possible, regardless of the model printed. Then assuming the printer is doing the right thing, adjust margins in the CAD to make the parts fit (hopefully) on any printer. Sounds reasonable!

Unfortunately, different firmwares and different slicers require different calibration techniques! There's a lot of software-specific advice out there, like printing a single-wall calibration box and measuring the wall thickness. That's a good technique for Slic3r, but not for Simplify3D. It can be very confusing.
Here's the general outline of what you should do:

Rough calibration check for printer steps/mm. Do the values in your firmware settings make sense for your linear motion hardware? For example, you can calculate what the theoretical values SHOULD be based on belt pitch and pulley tooth count. Print something moderately big (~100-200mm) and check if it's +/-1-2%. If it's off by more than that, your steps/mm is probably wrong.
Check for mechanical backlash using a backlash-checking print like this one: http://www.thingiverse.com/thing:252490 Tighten belts and perform other printer-specific tuning required to eliminate backlash. Backlash will throw off other calibration steps, so make sure there's no slop!
Follow the recommended extrusion volume calibration steps for your slicer. This starts with measuring your filament diameter with calipers and inputting that into your slicer. And then you will usually either "print a single-walled box and measure the thickness" or "print a series of 100% infill calibration boxes and adjust the extrusion multiplier to the largest value that looks good without bulging." By measuring filament diameter and then adjusting an extrusion calibration setting in the slicer, you will be able to measure future filament and prints will come out right. Giving the slicer fake diameter values will force you to recalibrate every time the diameter changes. Note that you must redo this calibration for each FILAMENT MATERIAL and EXTRUDER DESIGN. Different material/extruder pairs will have different bite depths and effective drive diameter.
Precision calibration check by printing a variety of object sizes and PLOTTING "desired size" as X and "actual size" as Y. Then find a linear fit equation, y=mx+b. (Do this separately for your printer's X, Y, and Z axes.) The value "m" is your scale error. You can use your slicer object scaling to fix this. For example, ABS usually requires 100.3-101% scaling to account for shrinkage. If you have scale error with a low-shrinkage material like PLA, you can adjust your firmware's steps/mm value to compensate. The value "b" is your fixed width error. Assuming you don't have backlash, this is usually caused by the small amount that molten plastic bulges out to the sides, or by extrusion volume calibration error. You can improve this by fine-tuning your extrusion volume. Many slicers also have "horizontal/XY size compensation" settings that you can use to shrink/expand the part by b/2 to correct the fixed width error. Any residual fixed-width error that you cannot correct with slicer settings should be added as a tolerance in your part models.

If you follow these steps, you should get +/-0.1mm or better dimensional precision on your prints.*
*Deltas not included. That's a whole other ball of wax.

Great post! I do actually have a delta (the Kossel Mini), but I am sure most of your suggestions can be related to some degree. Either way, I think this answer deserves to stay for the reference! :)

I think it's important to remember that a 3D printer is both an R&D tool and a piece of manufacturing equipment. As such, we should treat it and it's process similarly to other pieces of manufacturing equipment (ie mills, saws, etc.). Other (albeit traditional) manufacturing methods such as a mill will typically require post-processing to parts to remove any burrs and clean the parts. Since tools like a mill are a subtractive technology, it can already hold tight positional/dimensional tolerances. However, as 3D printing is additive manufacturing, it's difficult to hold the same tolerances directly out of the machine as compared to traditional tools.
For this reason, I would suggest planning time for a more traditional process after the print if tolerances and connections are a concern. This could be as simple as using a Dremel or using a mill/lathe. I would recommend increasing your shell/floor/roof settings in your slicer to accommodate the subtractive process though.

That is some very reasonable advice! I usually forget to add that extra shell/floor/wall when designing, and end up fiddling with some dremel tool on a model not fit to the task.

Glad to help. I've often screwed myself over during post-processing like reaming a hole to size and end up cutting too deep into the part and reveal the infill. I'll typically decrease my hole size in my CAD model by about 0.010" and increase my shell to about 5 or 6 to ensure I can ream the hole without this issue.

A few suggestions I haven't seen explicitly stated in the other answers.
Export resolution
When you export your STL files you can increase the resolution. If dimensional accuracy is extremely critical, you'll want to confirm that the STL conversion process hasn't altered the dimensions of curved surfaces outside your max min tolerances. I.e. open your STL file in you CAD program and then re-measure the resulting surfaces. STL conversion for holes makes the wholes slightly smaller, and external curved surfaces slightly larger.
Material Swell
I've noticed on my printer that parts are typically slightly larger when printed. I've managed to account for this in my CAD model by shrinking certain dimensions slightly in CAD prior to exporting them. My dimensions are typically off by about 0.1-0.2mm in XY, which if you're making something with close fits it's worth tweaking the file prior to printing.
Warping
If I've got a part that needs to be perfectly flat, I'll use a raft with an additional ring  (or two) of helper discs surrounding the part. For the flattest side I'll also print this on the build plate. If you've got two or more, best judgement.
Angled Flats
If i have a part with flat surfaces that are at angles to the the build platform I'll slow my extruder way down, 10mm/s is my go to speed. Keeping the extruder moving slowly will help to ensure that your edges and walls will be relatively smooth and with the least amount of distortion.
Calibration and setup
Everyone has said it, I'll say it again. Check your printer prior to a critical print. Any sag in your belts will cause drooping, Print a test part to ensure that your temperature settings are good for your filament, and that your extraction distance will minimize stringing.
I do a few test prints with a new filament and again about half way through a roll to ensure everything is still working properly, and if needed I'll tweak things as needed.

I print several pats that use 2.5mm "Pogo pins" which are spring-loaded electric contacts.  I've found that many variables will influence the size of the holes I have in my design.  Flow, temperature even different brands of filament will change the final size.
I create a profile for each part and specific filament.  That way I can make changes without changing other parts/projects.  Then I print a test piece with some 2.5mm holes and a few that are a few tenths of a millimeter larger and smaller.  I also make holes in the test piece that are vertical and some that are horizontal as I've found that orientation to the layers makes a difference.
I then fit the pins in my test piece and note which orientation and diameter fit best.
After that, I lock down every variable I can think of!
I added some desiccant beads to my filament storage bins and found even that increased the diameter of the printed holes.


text:
Understand and developing firmware - IDE help
Lately I've been working on tweaking firmware to fix functions on my printer.  A few of my biggest issues are lack of understanding of C and finding out how the multiple cpp and h files are linked.  Most of what I am doing is easy enough to do with copy and paste but with most firmwares having 30+ individual files it's hard to find where each parameter comes from or goes to.
I've been looking at Eclipse with an Arduino plugin as well as Visual Studio (or Atmel Studio) with the Visual Micro plugin.  What I would like is an easy way to view where each parameter is used, maybe highlight the parameter and it shows all instances or something similar?  Is there any IDE that offers something like that or is everyone using the Arduino IDE for firmware development?

I'm voting to close this question as off-topic because it is not about 3D printing, but a General programming question. Please Ask this on [so].

It is about 3D printing, very unlikely to receive an answer about firmware with multiple cpp and h files written for Arduino in a programming community.

What specifically would you like to modify in the firmware? That might be more related to this forum! :)

HI, I have just come across this question, and I think it is rather useful, for two reasons. (1) We seem to be changing the scope of SE 3D Printing, as per one of your meta posts and Game plan - What is on-topic?, and 3D Printing related coding would be on-topic now, and (2) Users new to 3D printing will probably encounter having to upgrade their firmware at some point, so a question about that here would be a good starting point.

As far as I know, Marlin - assuming that is the firmware you are using - is a standard C++ (the big brother of C) project that can be opened and compiled in the Arduino IDE, but also - at least - edited lots of other IDEs.
Depending on your OS, there are several alternatives. Visual Studio, Atmel Studio, Qt Creator, XCode, Eclipse, Visual Studio Code, Atom, Sublime Text and the Arduino IDE are just some of them.
I also believe that this question should be moved to StackOverflow. However, if you have questions as to how you can make specific modification to Marlin, this forum is the right place to ask. If that is the case, consider reformulating your question!


text:
Installing E3D v6 extruder electronics on Ultimaker Original+
I printed the mechanical parts to mount a E3D v6 on my Ultimaker Original+. But I don't know how to connect my heating cartridge, my thermistor and my 3 fans to the electronic board. Any idea?
Edit: I should have said I'm using the following design: https://www.youmagine.com/designs/e3d-v6-hot-end-mount
My main problem is to connect all 3 fans, as the original design of the UMO+ is only using one.

Hi, Alexis. Could you please elaborate on what specific electronics you have and want to connect? This way, your question can be answered by users who does not know the insides of the Ultimaker Original+.

I'm not certain exactly what you're asking, but I'll give this a try. If I've misunderstood, please give more details.
It sounds like you're upgrading to the E3D v6. If so, the heater, thermistor, and fans should connect to the same places as the previous ones did. The exception would be if you had thermocouples instead of thermistors before; that's a more complicated change.
If the connectors are different, you'll need to get matching connectors from a parts supplier (post a picture if you're having trouble identifying them). Fortunately each of the items you mentioned has 2 wires, and for the heater and thermistor polarity doesn't matter.
For fans, polarity does matter, so match up red vs. black, or just try it one way, and if the fan doesn't turn, then swap the wires. Some fans have a third wire, which could be used for measuring the actual rotation speed (see [http://pcbheaven.com/wikipages/How_PC_Fans_Work]); but it's not necessary.

I'm using that design: https://www.youmagine.com/designs/e3d-v6-hot-end-mount and I'm mainly looking to connect the 2 additional fans.

You should be able to just splice the two fans together (red to red, black to black), and connect that where ever the extruder fan you already had was. There should be plenty of power for 2 small fans. If the picture I found at http://wiki.ultimaker.com/images/El1.5.4-PCB.jpg is  right, I think the extruder fan connector is the one all by itself at the lower right.

Actually, the UMO+ has an UMO2 board: http://www.printme3d.com/media/catalog/product/cache/1/image/1010x850/9df78eab33525d08d6e5fb8d27136e95/m/o/motherboard.jpg All 3 fans are 12V.


text:
Levelling heads for dual extruder
I upgraded to a dual Mk9 extruder, and quickly discovered how critical it is to get the ends of both nozzles exactly level with each other -- that is, equally distant from the build plate at all times. Otherwise the lower one will crash against the plastic just extruded by the higher one.
So, what's a good procedure for getting the nozzles accurately level? About all I've figure out is to move the heads down close to Z=0, and then run X and Y back and forth and eyeball and adjust; then move even closer to Z=0 and repeat. Is there a better / more efficient way?

Do you have a bubble level?

Several; hadn't thought of that. Interesting.

When I get home I'll write up a proper answer if nobody beat me to it. Basically, use a bubble level to get the nozzles as level as you can and then use an index card with the nozzle close to the bed to fine-tine it.

Does your machine not have a leveling routine? MakerBot machines have it built in the firmware to move to various points around the build plate so you can adjust the knobs. Easier than jogging it around manually lol

Since I built this one from scratch, that would be a "no". :)  But I haven't had any trouble getting the bed level; it's the relative heights of 2 different nozzles that I'm finding tricky.

Make sure that the bed is level. As the saying goes, a level bed is next to godliness or something like that. Pay extra attention to the direction the nozzles are offset by (if one nozzle is offset on the X-axis, pay extra attention to the bed leveling along the X-axis). This can be done with just one nozzle and a business card or piece of paper.
Use a bubble level to get the nozzles about right. Move your z-axis up a bit and put a bubble level against the nozzles. Adjust as necessary so it's exactly level. The nozzles should be level enough that the bubble stays in the middle.
Fine-tune it with a business card. When you home the z- axis, you should be able to just fit a business card under both nozzles with a moderate amount of resistance. Don't force the card. If sliding the business card under produces a different amount of resistance for one nozzle than for another, adjust the nozzle a tiny amount. You can also use an index card or playing card.
Once it passes the card test, try a test print. If it doesn't work, make sure your bed is level, your nozzle offset is correct in the slicing software, and try calibrating with an index card again. If the nozzles become way off, try the bubble level again.

As for physically adjusting the level, another answer suggests shims made from aluminum foil, which work well. Personally, my extruder was off-level by almost exactly 1mm, so a pair of washers worked nicely for that.
Happy printing!
Leveling with a bubble:

Two good options for ROUGH alignment:

For threaded thermal barrier type extruders: use a leveling jig
like this while the extruders are disassembled:
http://www.thingiverse.com/thing:23013
For straight-shaft thermal barrier type extruders: Carefully level
the bed to whichever nozzle is lower, using your preferred piece of
paper / business card / feeler gauge. Then stick the same paper /
leveling tool under the higher nozzle, release the set screw or
clamp on the tube, and drop it down to rest on the leveling tool. You can also use a printed jig if your thermal barrier tubes are stuck and need some force to move.

The best and easiest way for FINE alignment:
Shims.
Just stick some folded-up aluminum foil (or layers of Kapton, or whatever) under whichever end of the cooling bar is lower, and tighten the screws holding it onto the carriage. Re-adjust as needed until perfectly level. This is ten times more accurate and much easier than trying to get precision alignment of the thermal barrier tubes in the bar itself.

Another option, that I found was the simplest one that worked for me:

Level your bed using just the first nozzle (temporarily lock the 2nd nozzle higher than the 1st one).
Move the printhead at the center of the bed
Loosen the grub screws on both nozzles (IMPORTANT, don't skip this step)
If you're not using a glass bed, temporarily clip a sheet of glass on your bed.
Home the Z-Axis
Move the the head sideways, front and back a few times just to be sure (X, Y)
Move the printhead back at the center
Lock the grub screws on both nozzles. Lock them slowly alternating between the top and bottom screws. Also make sure the wirings don't pull on the head (it's actually better if they push the nozzles down).
Relevel the bed, this time checking with the 2 nozzles

The sheet of glass ensures a completely flat and solid surface, on top of your properly leveled bed.
Try the above in case nothing else works for you.


text:
Comparative design methods for joints that will be joined together
I want to 3D-print some parts that will be later joined together along a seam. When modeling these separate parts, what are some methods that work well with 3D-printed pieces? For example, if I were doing wood working, I might choose dowel and pin joints or mortise and tenon joints or glue overlapping pieces. What methods translate well into use with 3D-printed plastics? How does the answer change depending on the orientation of the joint along the printing direction?

See: What is the best way to connect 3D printed parts?

One of my favorite techniques is to join pieces with screws, and include a tapered feature that helps align the parts. A single screw can give a very strong joint, that is well-aligned and won't twist. Another advantage is that such joints can be printed in any orientation, since the tapered feature can be designed with 45 degree angles.
Here is a cross-section example of such a joint:


text:
MakerBot Replicator 1 Voltage Regulator Fix
My Replicator (you know, the one made of balsa wood) has blown a voltage regulator on its MightyBoard for the second time. The first time, MakerBot graciously replaced it. However, they replaced with the same model board with no apparent fix for the commonly faulty voltage regulator. I can't afford the now $500 replacement board, so my option is to replace the faulty component and hope no further damage was taken on the board.
As MakerBot Industries did not need me to send in my old board, I've followed these steps to try and replace the voltage regulator on the old board.
I've offset the voltage regulator towards the power jack, jumped the remaining pin on the voltage regulator to the remaining lead on the board (where the old voltage regulator was), but I'm confused what/where the green wire does/goes (mine is blue on my machine). The image looks like he just soldered it onto the heat sink pad.
I tried to test it by plugging in the power and the RGB LED strip. The stepper motor driver LEDs turned on, but the LED strip and none of the other on-board LEDs turned on. I'm not very seasoned when it comes to electronics, so can anyone explain what the actual pinout should be or suggest other ways to resolve this issue?
Update: Old Board Replacement
So far I've replaced the regulator on my old board with some success. Before the replacement, the board wouldn't turn on (on-board LEDs wouldn't turn on). Now, all of the proper status LEDs turn on, but the board seems to be stuck in a boot sequence. The LCD screen provides two lines of block characters (as it normally does when initializing), but just hangs up there. I tried connecting the machine to my PC to try and restore the board to factory settings and install the latest firmware. However, the PC couldn't find the machine and I began to smell a bit of burning. I'm not sure if this is a result of permanent damage from the original regulator failing, or improper installation of the new regulator.
I'm going to dig around a bit more before attempting this fix on my main board. I'll edit this post as I continue the project.
Update: New Board Replacement
So, I've now attempted the fix on the newest board (the reason for this question). The results of this board are the same as the old one. I actually get power on the main board, but the LCD screen just shows two solid lines. I've taken pictures of what I've done.

What's the part number of the regulator you're putting in? The pin assignments vary from one part to another, but you can probably find them from the part number online. Some parts have the ground pin also connected to a metal part of their case. The green wire from the board should be ground (no promises!)
Assuming you've got a voltmeter, you can use it to find out which pins on the board are power and ground (easiest to do before the regulator is installed...). Then once installed, check that you're really getting 5V versus ground on the remaining (output) pin.
Since 2 of these burned out on you, I suggest taking steps to reduce the strain on the regulator. Voltage regulators turn the excess power into heat. Some things that can help:

Use heat sink grease to conduct heat from the regulator to the circuit board, the adjacent socket, etc. Hot melt glue, as the instructions you linked to mention, won't likely provide as much heat conduction.
Attach a heat sink to the regulator, or a bigger heat sink.
Get more air blowing across the regulator. You could do this by moving the regulator slightly, adding a fan, adding something to redirect some air onto the regulator, etc.
Swap in a bigger voltage regulator (that is, one rated for more current)
Turn down the voltage just a tiny bit on your power supply (if it has a control for that; many do).

Let us know how it turns out!
Steve


text:
Updating firmware on Monoprice Architect printer
I just received this printer and while it seems to talk to Makerbot Desktop software I'm not sure if I should be trying to update the firmware.
The printer comes with firmware v7.2 and while Makerbot Desktop offers an upgrade to v7.5 I'm not sure if it's a good idea with this non-Makerbot branded printer.
I've also seen information on upgrading this printer to Sailfish v7.5, is this the same thing as Makerbot firmware v7.5?

The Monoprice Architect is is a bare-bones FlashForge Creator that has been re-badged for Monoprice. The Creator line is a very popular set of printers, so there is lots of good advice out there. The FlashForge Google Group is a good community to join: https://groups.google.com/forum/#!forum/flashforge
The entire FF Creator line, in turn, is cloned from the original Makerbot Replicator 1. So you can use Makerbot slicing profiles for the Replicator 1. Just keep in mind that Makerbot does not generally test new software revs with their older printers, and DEFINITELY does not test new software revs with competitor knock-offs. Sometimes they appear to break functionality for non-Makerbot machines on purpose. So recent versions of Makerbot Desktop may not "play nice" with your FlashForge. The most recent "known good" free slicer you should use with this printer is Makerware 2.4.x. You can find links by searching the FF Google Group.
On that note, you may have received instructions to use ReplicatorG with your printer. But RepG is abandonware: development stopped years ago. It should only be used for firmware updates, not as a slicer. You should also only use the most recent version posted on the Sailfish page on Thingiverse:
http://www.thingiverse.com/thing:32084
Using older versions of RepG with newer firmware revs will corrupt your EEPROM! Only use the version downloaded from the link above.
The firmware that comes with the printer is FlashForge's slightly-customized build of either Sailfish or Makerbot's Replicator 1/2/2x firmware. But here's the trick: Makerbot's Rep1/2/2x firmware is just an old, out-of-date, slightly customized version of Sailfish. Makerbot stopped keeping up with bug-fixes and feature additions a long time ago. Everything is Sailfish: just different versions. You should use the most recent official release version listed at:
http://www.sailfishfirmware.com/
Follow the instructions in the Sailfish manual from the link above, and RepG will automatically pull the right builds from the official mirror and populate a list of printer options to choose. The trick here is which build to download. As of 1-21-16, there is not an official Monoprice Architect build yet. Which would mean editing a machine xml profile to avoid the firmware throwing warnings. I STRONGLY recommend getting used to the printer using factory firmware before trying to fight with custom machine profiles... But here is the basic process to pick a Sailfish firmware build when you're ready:
First: which Atmega processor version do you have? The large chip in the middle of the control board will either say 1280 or 2560. You need to know which version you have. Bad things happen if you load the wrong version.
Second: What is the tooth count on the X and Y drivetrain pulleys? To my knowledge, FF always uses 17-tooth pulleys, which matches the Replicator 1 and FF Creator profiles. The Rep2 and 2x use 18t pulleys, so only use those builds if you have those pulleys. People often mess this up and their prints end up with dimensions ~5% off in X and Y.
Third: The Architect has one extruder and no heatbed, so firmware builds that expect those to be connected (Rep 1 Dual, Creator, etc) will throw errors if loaded. You can fix this from the LCD screen or RepG, but that's a whole separate question. Do some printing and learn about the printer before attempting any firmware update so you'll know what to do if you pick a build with the wrong parts.
Fourth: This one is just for the sake of completeness. Some FF models were shipped with off-spec heatbeds that require special firmware builds to prevent drawing too much current and overheating / overloading the power supply. The Architect doesn't have that, but firmware builds for those printer models (eg I believe the FF Creator 2560) will under-power regular heatbeds. This is just something you need to know with the Architect if you decide to install a heatbed later. But it's a really critical safety warning for people with those off-spec heatbeds.
If this all seems complicated, that's because FlashForge (and in turn Monoprice) relies heavily on the open source Sailfish project to maintain the software ecosystem behind this line of printers. FlashForge has some internal builds that they use for flashing new bots, but these are not kept particularly up-to-date. Nor does FlashForge release the source files, so it's quite opaque where exactly the stock firmware differs from mainstream Sailfish. In the long run, you should install mainline Sailfish. But it's ok to stick with the factory firmware until you get used to the printer.
To summarize: Because there is not an existing Sailfish build, you're going to need to do some investigating and some experimenting to figure out which build will work. Don't try that until you're familiar with the printer. Post on the FlashForge Google Group when you're ready for help.

I've just recently used the MakerBot Desktop (v 3.8?) on my Replicator 1 and worked out fine. It's nice because it provides a more user friendly interface for changing various settings (better than opening and deciphering a JSON file). I wouldn't recommend anything between MakerWare 2.4.? to this new Beta of MakerBot Desktop though

Since the printer has no heater, I'd advise some sleuthing

Look at the motherboard.  Find the big black square chip and see if it is a ATmega 1280 or 2560.  Likely it's a 1280, but you never know.  This will impact which firmware build you use.
If you will eventually add a heater PCB, then figure out the size (wattage) of the power supply.  It may be big enough now for a heated platform, or maybe not.  I guess you can cross that bridge if/when you add a HBP (heated build platform).  However, it can make a difference as to which firmware build you load as some builds of Sailfish will intentionally serialize heating so as to not put too high of a load on the power supply (PSU).

Armed with the above info, you can then decide if you want a 1280 or 2560 build of Sailfish.  And if you want a build which will serialize eventual use of an HBP or not.
Serialized: MakerBot Replicator 1 Single & Dual (implied ATmega 1280), MakerBot Replicator 1 with ATmega 2560
Non-serialized: FlashForge Creator I, II & X (implied ATmega 1280)
For a non-serialized, 2560 build know that the FlashForge one is for a poorly behaved heater PCB and you likely won't want it.  That sort of leaves you without a good, non-serialized choice.  In a pinch you can use the ZYYX 3D build for a 2560.  Or you can contact the Sailfish team directly: speaking with very certain knowledge, I can assure you that they'd be happy to do a targetted build for your machine.  However, at present they lack info to do so (e.g., build volume, distances from endstops to center of build platform, etc.).


text:
Cura with Pronterface UI stops printing
When I use Cura with the Pronterface UI it sometime just stops printing.
When it stops the printer just stops, the UI looks like it's still printing but nothing is moving in the printer, also, trying to control the printer from the UI does nothing.
It always stops early in the printing process, usually during the auto-leveling process or while printing the skirt, the latest it happened was during the first solid layer of a raft.
Usually closing the printing window and re-opening it solves the problem but not always, this never happened to me with the basic UI, I couldn't find any settings that makes the problem better or worse, it just happens randomly.
Anyone knows how to stop that from happening?
My printer is a Robo 3D R1+
Update
After installing a screen on my printer I discovered Pronterface is sending a "Wait for user" G Code to the printer.
Because this changes the question too much and invalidates the existing answer I've asked a new question at What makes Pronterface wait for user?

Have you tried to printing from a different source, such as a SD card? If this works well, it is probably not the printer itself that is the problem. Does the screen go blank for a moment before it happens? If it does, it could be that the arduino receives a "connect" command from some other process, and cuts it current action. Could it be any of these, you think?

@TormodHaugene the problem happens only with cura and the pronterface ui, both SD card and cura with the basic ui don't have this problem. I really don't know if the problem is in the printer or the software

So if you leave Pronterface out of it all, everything works just fine? Then I would reconsider using Pronterface for direct printing altogether. In my opinion, needing to have a computer always connected is sort of unnecessary. Are there any particular reason why you want to print directly from Pronterface?

@TormodHaugene my printer does not have a screen, so if I want any manual control what so ever I don't really have a choice (a screen is currently on its way from China, but it takes a while to arrive)

Oh, I see. That makes it a bit more complicated!

After installing a screen on my printer I discovered Pronterface is sending a "Wait for user" G Code to the printer.
Because this changes the question too much and invalidates the existing answer I've asked a new question at What makes Pronterface wait for user?

A problem I have come across when using Pronterface is that the operating system starves the resources of the program if the program's window is not in the front.
If I, for instance, started a print, then started browsing the web, it would sometimes suddenly stop. When bringing Pronterface back to the front, it would take a few seconds, and then continue (if I remember correctly).
On OS X - which I am using - I believe this is called app nap, while a similar mechanism exist for Windows. I ended up printing form an SD card myself after this, but you might want to try manually setting the resource priority for Pronterface in your OS.
In Windows, you could trying to increase the resource allocation for Pronterface by going to Task Manager -> Details -> Right click the Pronterface process -> Set Priority. I would be careful to set it too high, since you are basically allowing the program more juice to potentially do something wrong.
In OS X you could try to disable app nap for Pronterface.

That's not it, just happened to me while the Pronterface window was the active foreground window


text:
How can I set the position in Pronterface?
I'm in the process of building a 3D printer and have all the stepper motors wired up and the controller connected to the computer running pronterface.
I can move each axis and also send g-code to the printer.
Now how can I define the current position to be the 0/0/0 position?
I'd like to move the printer into a position where I think should be the zero position and define it as such in pronterface somehow.

G92 X0 Y0 Z0

tells the printer that the current position is (0,0,0).

There's a handy list of G0-codes at http://reprap.org/wiki/G-code -- though the list is too big to be convenient for finding a code if you're not already sure what it's called... :(

Ctrl+F is your friend. :)


text:
Is this fuse a good choice for my Prusa i3's power supply and RAMPS 1.4?
Wondering if this fuse is safe to use in this switch/plug to turn on /off a 12V DC 30A Power Supply 360W Power Supply that will power a RAMPS 1.4 board for a Prusa i3 with an external led display that contains an SD Card Reader.
I found the suggestion to use it here.

What's with the down vote?  You be troll'n?

It's really not a 3d printer question, it's an electrical engineering question that just happens to be about a 3d printer.

@RyanCarlyle oh, well somebody move it to the Electrical Engineering Stackexchange then...no that's a bad idea, this site is in beta and needs the help.

Fair point. Maybe the question could be "Is this fuse a good choice for my RAMPS Prusa i3?" or something like that :-)

No, do not use this fuse. The current rating is too high to be reasonable for your printer. It will "work" in the sense that your printer will get power, but it won't provide anywhere near as much protection as a lower-rated fuse.
10A is a lot of current for mains voltage. Depending on what else you have plugged in, there is a fair chance your home's 15A breaker will trip before this fuse does, which kind of defeats the point of having it.
Even for "fast" fuses, it takes a significant amount of time for them to blow when conducting their rated current. The internal fusible link has to heat up and melt before the fuse stops conducting. The less the overload current exceeds the rating, the longer that takes. A 10A fuse conducting a 10.5A short might take 30 seconds to trip. In the meantime, your printer is melting. Lower-rated fuses will trip faster for the same short and thus provide better protection.
You need to size fuses as small as possible for the required current draw if you want to have any hope of rapidly cutting off an excessive-current event.
I would recommend a 4A fuse in the USA for this 350w power supply. (Note: the listing title says 360 but the photos show 350.) I use 4A fuses in several printers with 120v / 350w PSUs and they do not trip. But you can do the math for yourself:
350 watts / 120 volts / 80% efficiency = 3.64A
The smallest fuse you can find that is larger than this value is what you should use.
Now, we can argue over whether 80% is the right efficiency value... it could be lower. The PSU label says 6.5A input is required, but that amount of current draw implies either a <50% efficiency (which is quite poor for this kind of PSU) or would only occur for abuse/surge scenarios like starting very large motors. Such short-lived inrush events generally won't trip a fuse unless you do something dumb like lock the rotor. And none of that applies to the small microstepping-driver stepper motor systems we're working with here. This PSU should not draw more than 4A in normal 3D printer use.
Looking at this on the other end -- how much damage will 10A do versus 4A? Lots. If the short is in the 12v system, and the PSU's short protection doesn't trip in (because it's a cheap knock-off) you would roughly multiply the AC fuse current times 10 to get the DC current. And 40A is a downright scary amount of current! Depending on wire gauge, putting 40A through heatbed wiring may make it smell and smoke. Whereas putting 100A through heatbed wiring will almost certainly start a fire.
You're much safer with a 4A or even 6A fuse for this PSU than a 10A fuse.

Should also point out a 1-star review on the switch's Amazon entry that said it melted after an hour at 4.5A... Although it seems like a lot of different switches are sold under this listing. I actually have one of these from this exact Amazon listing  in a printer right now, and the wiring to the onboard switch is very small. I would trust the main terminals to 10A but not the lighted switch part.

So another words, with the fuse we're using the fuse to prevent power spikes coming in from the wall outlet that might send too much DC power to the heatbed and electronics and catch them on fire?   So you don't think the switch is safe?

Most often, the fuse is there to kill power in case there's a short in your mains wiring between the switch and PSU, which may be quite destructive before your home's circuit breaker trips. Or the fuse may trip if the PSU fails and starts drawing excess current. Having an oversized fuse may allow the switch to melt down without tripping any kind of protection.

MOST of the time, shorts in the printer's wiring will be caught and stopped by the PSU's built-in over-current protection. You shouldn't really rely on that though if you're buying clones rather than name-brand PSUs (like the MeanWell that this PSU is copied from).

The switch should be fine for 4A, I'm putting around 2.5-3A through it without any issues, but I don't know if I would trust it to 10A.

Another words don't wire the PSU up to anything that pulls more electricity than the 3D Printer will?  Because the printer only draws about 4A (or is that the PSU?)

The printer will pull up to 29A at 12V DC from the PSU. I don't know your component specs (particularly the heatbed) so I can't calculate the exact draw. Realistically, you can probably hook up 20-25A worth of load to the PSU and it should be fine. (Depends a bit on the PSU build quality.) THEN, in order to provide up to 29A @ 12VDC to the printer, the PSU will draw up to 4A @ 120VAC from your house wiring. The input and output POWER are the same (less conversion efficiency losses)... but the current and voltage are different.

If your printer only needs ~15A to run everything, the PSU will only draw ~2A from your house wiring. It's just a converter. It drops voltage and raises current.

I went to an autoparts store and got a 4A fuse for my switch.  But I think it's DC since it reads 32V on it and there's no spring inside, it doesn't perfectly fit in the fuse cabinet inside the switch.  I was reading that there are AC and DC fuses, so I guess the need an AC one, since the power is coming in from the wall outlet via the switch as AC.  Right?

You need a fuse rated 125v or higher. If the fuse says 32v, it's probably only rated to 32v.

And an AC fuse right?

If I'm not mistaken, any fuse you find rated to 125+ will be intended for AC. DC circuits over 24v are pretty rare.


text:
Which resolution is needed for bricks compatible with Lego?
I found a story about someone 3D-printing equipment for their Lego minifig, using an Ultimaker. (Article is in Dutch, but accompanied by photographs).
I noticed that what they made weren't the actual connecting bricks, but the tools used by the minifig. And that even so, some filing and a dremel were needed afterwards to make them fit properly.
I'm told that to make something connect properly with real Lego, the machine needs to be tuned very precisely.
So, what resolution is needed to print bricks that will connect with normal Lego bricks?

It's really more about calibration than resolution -- a poorly calibrated printer will have dimension errors that prevent mating with true LEGO bricks or other printed bricks.
Also, "resolution" is an incredibly loaded term for 3d printers, because it can mean a lot of different things. But we don't need to get into that right now. There are really two big things to worry about: layer height and extrusion width.
Layer heights of 0.1mm or 0.2mm should be fine. Coarser layers may run into surface finish issues that make the bricks difficult to put together or take apart. There probably isn't much reason to go finer than 0.1mm for this application. Almost all FFF printers can do 0.1mm layer heights as long as it is reasonably well-tuned.
Any typical household FFF printer with a "normal" nozzle size can print fine enough for the bricks to work. It just needs to be tuned well. The smallest "must have" feature in a standard lego brick is the 1.6mm thick wall around the sides. The typical minimum printable feature size for an FFF printer is 2x the extrusion width, because the slicer will place a path on the inside edge of the shape and the outside edge of the shape. (Some slicers will allow single-extrusion features, but this is not generally recommended because it makes weak parts.)
So, how wide is the extrusion width? It's adjustable, and different slicers auto-recommend different values, but as a safe rule of thumb it needs to be between 1x and 2x your nozzle size. There are some volume calculation quirks in different slicers that may encourage larger or smaller sizes, so sometimes people recommend [extrusion width = nozzle size + layer height] particularly with Slic3r. This is very system-specific.
Assuming you have the most common stock nozzle with a 0.4mm orifice, and also set the extrusion width to 0.4mm, the slicer should put four strands in the walls of the LEGO brick. That's good.
Where it gets tricky is if you have an extrusion width that does not evenly divide into 1.6mm. Say you are printing with an extrusion width of 0.6mm. There is enough room in the wall of the part to place two full 0.6mm perimeter strands... but then a gap 0.4mm wide will be left in the center. You can't put another 0.6mm strand into that 0.4mm gap. Different slicers handle this different ways. Some will leave an empty space between the walls, and you get a very weak print. Some will mash an excessive amount of plastic into the gap, causing poor print quality as excess material builds up more and more on each layer. Some will push a smaller-than-commanded strand to try to properly fill the volume.
So, the general advice with small features is to make sure your extrusion width goes into the part's minimum thickness a reasonable number of times.

[Feature size / extrusion width < 2] is BAD
[Feature size / extrusion width = 2] is GOOD
[2 < Feature size / extrusion width < 3] is BAD
[Feature size / extrusion width > 3] is GOOD

Although these will vary somewhat by slicer -- older slicers like Skeinforge tend to have more issues with this than newer slicers. What you should do in practice is check your slicer's print previewer to see whether it is leaving a gap between the strands. Then adjust extrusion width and perimeter/shell count to try to get an intelligent output. There's some trial and error involved.

The smallest "nice to have" feature is a tight fit so bricks snap together properly, and IIRC, 0.1mm is far too large for that.

Whether 0.1mm tolerance is adequate depends on the plastic -- nylon, sure, PLA, nope. ABS (like real lego bricks) may be ok. Most of the 3DP-oriented brick designs I've seen modify some design details to make them more suitable for somewhat looser tolerances.

That said, if you're tuning specifically to print a single type of thing over and over, you can hit +/-0.05mm or better pretty consistently. The motion system resolution in a typical household/hobbyist 3d printer is 10 micron and plastic volume control precision adds a little variance onto that. The design clearance between actual lego bricks is 0.1mm, for example, so 0.05mm should be adequate.

Some looking around says that Lego has a mold tolerance of 0.005mm, which apparently translates into 0.01mm in the finished parts.

Yeah, we're simply not going to hit that with hobbyist FFF printers. I think people making their own bricks will generally tolerate a little bit less consistency in "snap-feel" though.

I printed a few blocks in PLA, with a 0.4 nozzle; the printer wasn't perfectly tuned, but the blocks still fit, barely. So with really careful tuning it may work ok.

I have notes about printing Lego bricks here:

https://www.thingiverse.com/thing:3424550

The upshot is, you want to align the wall thickness of your brick model edges to match an exact multiple of nozzle thickness of your printer. This is more important than using an STL file that exactly matches real Lego dimensions, because your slicer and printer are unlikely to be able to match those dimensions anyway. And because of that, you'll need other adjustments to the bricks to help them fit well with each other and with real Legos.
Additionally, while it is well-understand that Lego bricks use a 1.6mm "Lego Unit" for their standard edge thickness, it's less-well understand how they use an additional .1mm "Play Factor" to help bricks to fit together better. Based on my tests, this play factor is removed from both sides of an edge, such that a standard Lego edge wall should be 1.4mm thick.
Put this all together, and I've found you want to aim for 1.2mm edges when using a .4mm nozzle, and 1.5mm edges when using .5mm nozzle.
Alternatively, a .4mm nozzle can do real 1.4mm Lego edges by only using 1 line for the outer walls, and filling in the remaining .6mm of thickness. Personally, I never want to use just 1 line for a wall, and 1.5x the nozzle diameter is also the bare minimum I'd trust for filling in to work well, making this plan a challenge, too.
The thingiverse piece I linked to is actually a customizable brick generator, that will let you make fine adjustments and help you create brick STL models based on your printer, your slicer and settings, and your material, that will print well and fit with other bricks.


text:
Advantages of PETG filament?
I was just shopping for filament, and saw some glowing claims about PETG being as easy to work with as PLA, but as strong as ABS, and less brittle. Anyone know if that's actually true, or what the tradeoffs are?

PETG is great stuff to work with. It is stronger than ABS also. It prints slower than ABS and PLA. The formulas vary quite a bit from vendor to vendor. I have used 3 brands, and each of their properties vary.
From my experience you do have to be careful with moisture. You'll be able to tell you have moisture in your filament if you start hearing a slight hissing and popping and an increased number of structural zits on the object. Moisture will also increase the problem listed in Mark's post below regarding the accumulation of filament on the nozzle.

I absolutely agree with you on all points, @Asa. However, be careful about making subjective recommendations about products, as that is generally frowned upon in the Stack Exchange community. In this case, you could try to describe the difference between different kinds of PETG based on their properties rather than simply saying that one is "better and cheaper" - if you can! (Also, adding a reference that says the subjective opinions for you could help argue in such cases.)

Thanks for comment and I will make shure I put more substantive information. In my replies.

The post is now much better. Thank you for taking your time!

I have never used ABS, because I have a young child at home and no ventilation system (just to be safe). I have however used PETG, a crystal clear brand competitively priced on AMA-ssive online retailer, I loved it and will probably only buy it in the future.
Advantages Noted:

There is no odor I could detect
It is remarkably clear, like glass using a large nozzle (1.2) and layer diameter.
It flexes without breaking I'm guessing what seems like about 10-15% more than PLA.
In other words if I print a large circular ring I can squeeze the ring about 10 to 15% farther without the ring cracking or breaking.
The material itself is more dense, identically printed items have more weight to them and feel sturdy.
It has a higher glass transition temperature

Disadvantages  noted:

It's a little more expensive, but not prohibitively so (like carbon fiber).
It requires a higher printing temperature, so uses more power.
I havent perfected my retraction settings, and I have read others having similar issues with excess stringing. IOW it oozes more than PLA.
Switching between this and PLA requires extra care and time to ensure the nozzle is clear. I guess that is the same with any other alternate material as well.

In addition to what @AsaDeDeBuck said, PETG is also more flexible than PLA, and less stinky than ABS. Furthermore, some PETG variants like to accumulate on the nozzle (particulate build up) and then char a bit before being deposited at some random spot on the object.

I've experienced this accumulation of material on the nozzle also on my first builds with PETG. But after raising the temperature to 260 degrees and the print speed to 70 mm/s it never happened any more. Of course I only have experience with one particular type of PETG (Real-Filament).

PETG is great, but definitely not as easy to print as PLA. However the advantages of higher impact resistance, temperature resistance and longevity make it superior to PLA for parts that require those properties. ABS is even harder to print than PETG and has worse strength and layer adhesion so no reason to bother with it in my opinion.
I print PETG at 80°C bed temp on PEI bed material, with 250°C nozzle temp. At first I was trying my old BuildTak bed material and it works at 40°C but the base of my parts was warping up some, it still worked but they didn't come out flat.
If you raise the temp on BuildTak to 80°C bed then the PETG permanently bonds to the BuildTak and rips up pieces of it upon removal.
PEI at 80°C keeps the base of printed parts perfectly flat (up to a certain part size/thickness) and has good adhesion and release properties with no wear showing on the bed after many prints.
If your parts are 100% infill and over about 3/4" (20 mm) tall you may still have problems with the base not ending up completely flat. In such large rigid parts the upper area that does not stay properly heated through conduction from the bed will shrink some and pull the lower sections up with it. Lower fill density like 50%, 20% help with this problem.
PETG build up on the nozzle was a real problem for me until I got a silicone sleeved hotend, E3D is the only one who makes them that I know of right now, but I am sure there will be others shortly. This completely fixed the problem of filament sticking to the hot nozzle and later being deposited as black charred blobs.
Another thing to consider is moisture, after even a day in high humidity PETG absorbs enough moisture to undergo hydrolysis upon extrusion at 250°C and become very brittle. To avoid this I use a conventional food dehydrator with the plastic being fed from inside, you can lookup designs on Thingiverse.

I love PETG. When I first started I always used ABS because I thought it was the best and didn't see the point in using PLA. However, after a few years of playing around I no longer use ABS. I use PLA for when I am testing and PETG when I want to print something that will be used, ike parts or models.
PETG is a little more expensive, however worth it, as it is strong and easy to use. I normally print at 220°C on the nozzle and 80°C for the bed.
PETG has more flex to it so when you are printing parts it is less likely to break under pressure like ABS.


text:
Why is CLIP so much faster than SLA?
Stereolithography produces parts by projecting ultraviolet light on the top of a vat of liquid photopolymer, causing it to harden.  CLIP produces parts by projecting ultraviolet light through the bottom of a vat of liquid photopolymer, causing it to harden.  This seems like a minor difference, yet CLIP is reportedly much faster (I've seen numbers as high as 100x).  Why is this?

It's important to understand what specifically is being compared. CLIP is much faster than bottom-up technologies that require a peel step between every layer. For example, the Form1 galvo SLA printer tilts the resin vat to separate the transparent bottom from the print. That is, by far, the slowest part of SLA/DLP printing with most modern light sources. Where the speed comes in is that without a peel, a continuous "movie" can be used to cure the resin rather than a series of alternating images and peels.
Top-down printers can print dramatically faster than bottom-up-and-peel printers. CLIP is not necessarily faster than top-down. For example, the Gizmo 3D line of top-down printers are very similar in print speed to CLIP. (http://www.gizmo3dprinters.com.au/)
Most "consumer" SLA printers these days use bottom-up-and-peel techniques, because this has some practical advantages over top-down printers:

Way less resin is required to fill the printer when the part is pulled out as it builds rather than being lowered into the tank (along with the Z stage) as it builds. Resin is expensive. This also means bottom up printers can be smaller and have fewer mechanical parts such as leveling devices submerged in resin.
Standard resins contain an inhibitor chemical that prevents polymerization in the presence of oxygen, which causes the surface layer exposed to air (and low-level stray light) to not cure. So top-down printers must shoot light through a non-curing layer before reaching curable resin. This makes the tuning more sensitive and can somewhat reduce detail compared to a bottom-up printer curing right on the window.
Replacement vats or windows for bottom-up printers may be seen by manufacturers as a profit-generating consumable, since they have to be replaced somewhat frequently.
Top-down printers have to worry somewhat more about resin flow rates as the part is lowered. Air bubbles may be pulled into the resin or the fresh resin layer above the part may vary significantly in thickness if the part is submerged too fast for the resin viscosity. (Admittedly, bottom-up printers will experience excessive suction forces and potentially break off bits of the print at high peel speeds.)

CLIP is a bottom-up technique that doesn't require a peel step, because the vat creates an oxygen layer over the window that keeps the resin from curing directly on the surface and sticking. In that way, it arguably performs more like a top-down printer than a bottom-up printer.
Top-down printers that are designed to overcome the above issues and use high-intensity light sources can achieve exceptionally high print speeds. This includes similar "continuous" build techniques used as in CLIP.

The number of 100x could be true in some situations.  I wish I could see the part(s) that they printed to measure this 100x, but that is another story.
Looking at their videos they can move the build plate at a maximum speed of 10mm per minute.  You will see the Eiffel tower video where they have to change over to standard speed for flat layers.  It is because the flat layers stop resin flow and can't be printed using continuous printing.
Prodways have shown that they can move it at 20mm per minute, but again there are things that are not advertised/mentioned.  To achieve higher speeds you need to make the resins more reactive.  Making resins more reactive means the resins won't last as long in the vat/bottle.  So they expire sooner.  It also means they could harden under normal light conditions so it makes it difficult to work with.  If you look at the Prodways video you will see resin waste on the build plate.  That shows that the projector brightness was set too high.
Gizmo can print between 5 and 25 times faster than a leading brand of SLA printers, also depends on the number of parts and complexity on the build plate.  The decision was made to advertise the build plate moving speed, e.g. 3mm per minute, rather than the number of times faster than anything else, because that is a value that doesn't change with the number of items on the build plate, but it does change depending on the projection area size.
Imagine you just have a single line going upwards then most SLA printers could do it at the same speed.  B9 Creator (bottom up) users have actually shown they can do continuous printing when printing really tiny items with very thin walls, because they don't have suction problems in those situations.
Now when you add many small objects with small features on the build plate DLP printers will display the full layer in one go where laser based SLA machines need to draw out each part like an FDM machine.
Continuous printing does have limitations.  Resin needs to flow from the bottom or you will get resin starvation and cause holes so you might not be able to use it for everything.  You should see it as another tool in your printing toolbox rather than the be all and end all.
So after all that, the 100x depends on so many things, you shouldn't get stuck at looking at that number other than knowing it is a way of marketing the printers.


text:
How to edit Cura profile in Octoprint?
In Cura, I can edit my .ini profile settings as needed, for example, when I change filament or models. It's annoying to have to edit the profile on another computer and update it on my Pi just to change the infill, etc. I've searched http://plugins.octoprint.org/ and can't find any plugins that do this.

I noticed that your question has not had much activity lately, are you still looking for an answer to this question? How might we be able to close some gaps?

As far as I know, this is currently not possible.

There is an import function.
https://github.com/foosel/OctoPrint/wiki/Plugin:-Cura
Btw. now in Cura 2.1 you'll also need to reimport your .ini.
Regards :)

You can manually edit the .profile by using an SSH terminal program (e.g putty) to log into your Pi
Then cd ./octoprint/slicingProfiles
ls to see folders (on mine I see cura)
cd cura
ls to see profile files e.g fred.profile
sudo nano fred.profile
move down to where you can see the slicing parameters and edit away

This doesn't answer the question, which asks for a way to edit the profiles within octoprint. Editing them through SSH (from another computer) is exactly what the question seeks to avoid.

IDK, this seems like a pretty decent answer given you most likely access octoprint from a browser on another computer, so to putty in, is only another window, no editing of files and then having to FTP them over. Just edit in place.