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What is the benefit of using an ARM based electronics?
Most electronics use micro-controllers like an AVR, but I'm seeing ARM chips in new electronics. ARM chips are said to be more powerful, but in what areas related to 3D printing could this help?  What are the features that the AVR struggles with and where an ARM could be better?
High Speed movement? Delta printers? Graphic display?
And is the AVR really the limitation there?

3D printer controllers have to do a lot of stuff very, very fast. Performing kinematics and dynamics calculations while sending many thousands of precisely-synchronized step pulses per second is really, really hard. The 8bit AVR line of microcontrollers used in older 3D printer controllers is basically a late-1990s era Mr Coffee processor. They are completely, utterly maxed out on processor time just executing basic printing functions in simple (eg Cartesian) printers, and adding additional calculation load will bog them down and cause slowdowns, stuttering, pausing, and so on.
"But my 8bit printer works fine," you say. No, it doesn't. Your print performance is limited by it, whether you realize it or not. Slicers now automatically hide a lot of the firmware's performance shortcomings from you. For example, the standard practice of greatly slowing down print speeds on perimeters is largely a result of 8bit processors having inadequate resources for two things:

Performing centripetal acceleration calculations for curves
across multiple gcode segments
Keeping up with gcode transmission/processing and motion planning for gcode with lots of very small segments, such as in organic models or smooth arcs

When presented with a series of very small segments in a smooth arc or complex curve, the 8bit firmware will likely choke on the required command processing rate and introduce stuttering to the print. These incredibly brief pauses allow residual pressure in the extruder to push out some extra plastic, making a little zit on the print. So most slicers automatically decimate curves and output gcode with reduced resolution to lighten the load on the firmware. Problem solved, right?
But there's another issue -- the GRBL motion control algorithms underlying all the major open source 3D printer controllers were designed with lots of shortcuts and hacks to allow 8bit processors to execute fast enough. For example, the basic algorithm only looks at the speed or velocity change at the corner between two segments, and uses that to decide when to decelerate/accelerate along the direction of motion. It does not calculate or consider centripetal/radial acceleration whatsoever. This is a really effective hack when printing boxy, low-res models, but it fails miserably on smooth curves with lots of little segments. The firmware does not detect any appreciable velocity change at the corner of any two nearly-linear segments within the faceted curve, and thus does not slow down for the curve. So complex geometry is effectively printed at constant velocity, with no acceleration.
Printing complex perimeters unaccelerated means the commanded feedrate must be very low to get good quality. Most printers are limited to about 40mm/s or less on complex perimeters, despite being able to run perhaps 80-120mm/s on low-complexity infill before hitting other speed limits.
Between the command processing rate limits and motion planner shortcomings required by low power processors, print speeds must be much lower in practice than is strictly required by the physics and printer hardware. This all comes from 8bit processors. The workarounds and best practices to deal with this problem are so deeply baked into the toolchains and ecosystem that very few people realize there is even a problem. But it's a real limit that can be overcome: a high-speed processor running a more rigorous motion planner could generate higher average print speeds with better print quality.
That said, the ARM-based firmwares are only slowly moving towards more advanced motion planners. This is a big development area right now that is actually driving an upcoming shift away from low-end ARMs like the Cortex M3 towards even faster processors. It's actually not all that hard to max out an 84 MHz Arduino Due by piling on a bunch of firmware features.
The use of 8bit processors also makes printers LOUDER. The biggest consumer of processor time in a typical 8bit printer is the stepper interrupt that fires the step pulses to make the motors move. It is quite typical for >60% of all clock cycles on an Atmega AVR to go to firing step pulses. Because this occurs as an interrupt, other processing tasks that the printer must perform -- like acceleration calculations and heater control -- get squeezed into the brief spaces between stepper interrupt events.
Without careful firmware design, the step pulses will completely "crowd out" other functionality like LCD display updates and acceleration calculations. In order to allow higher motion rates without using all the processor resources, 8bit firmwares have a mode called "step doubling" that fires two (or four, or eight) step pulses per stepper interrupt so that half (or a quarter, or an eighth) as many stepper interrupts can be used to produce the same motion speed. This practice de-bottlenecks the processor, but it causes rougher and louder motor motion because the step pulses are fired in bursts rather than a constant frequency. In effect, the microstepping level of the motor is functionally dropped to a coarser mode when the stepper interrupt fires double or quad steps. So the motors get louder, less precise, and in extreme cases may have problems with resonance.
An interesting side effect is that if you switch a Marlin-based printer from 1/16 microstepping to 1/32 microstepping, and keep the same print speeds, the firmware will simply start step-doubling, dropping your effective microstepping level right back down to 1/16.
ARM-based firmwares also use step doubling, but the allowable step rates are typically ~8 times higher before double/quad stepping is used. That can mean higher speeds and/or smoother motion.
Another issue with 8bit AVRs is the lack of hardware floating point and need to spend many clock cycles on high-precision calculations or handling very large numbers. Delta kinematics, auto-leveling functions, calculating moves with extremely high step counts for large printers, and other advanced functionality all take a lot of clock cycles on an 8bit processor. Poor firmware design or carelessly adding a feature that requires a few extra square roots and trig functions can completely bog down the processor. This kind of feature creep and code bloat has seriously impacted Marlin's performance over time as people ask more and more of the old AVR.
In comparison, a 32bit processor doesn't just have a faster clock and more clock cycles, it is also able to do much more complex math in fewer clock cycles, because it has dedicated hardware functionality that takes care of many of the steps an 8bit processor must do in software.
Do 8bit processors work? Sure, they work surprisingly well for what they are and what we ask of them. But they unquestionably limit the performance and features of modern 3D printers. Even today's current generation of 32bit processors is already being maxed out by high speed printers and math-heavy features. The 8bit processor is already two generations behind what would qualify as a "modern" 3D printer controller.

If realtime math and computation is an issue, then why are there not many efforts in fully-programmable logic such as FPGA being used to drive stepper control and the like?

Aren't FPGAs expensive?

Extra cost and complexity.  Why coordinate two chips when you can use one faster chip? There ARE actually a number of FPGA-based projects out there, but none of them have hit critical mass for user uptake.

@RyanCarlyle The notion that two chips need to be coordinated isn't correct. An FPGA can handle serial in, parsing, planning, and stepping in one package (with soft-core MCU possible). Cost is a factor though.

All the attempts to use FPGAs I've seen to date used two chips, but thanks for pointing this out.

http://mobilegeeks.de/wp-content/uploads/2012/11/citizen-kane-clapping-gif.gif

Generally, AVR is in fact less powerful than many ARM cores used today. Most printers with AVRs don't have floating-point coprocessors, although a lot of the step and movement control can be done in integer-only math (except for G2/G3). Marlin can interrupt for step handling up to 10000 times per second on AVR, translating to 40000 steps per second. This isn't particularly useful without mechanical components that can move at those speeds and still print meaningful results (or are far more precise and have a far higher step-count-per-mm at a similar speed).
Graphic display isn't a particularly taxing thing to do at low speeds--high speeds or weird interfaces might require a bit more power or a dedicated interrupt.
The times when ARM might be important are for more math-heavy and especially floating-point-heavy setups such as delta, where every move requires many floating-point and trig operations, and navigation in menus on a 16MHz AVR (atmega2560) is described as "painfully slow", but Marlin does succeed in printing meaningful results on delta-style printers.
Clearly, an ARM core that is either faster at performing soft floating-point, or supports hardfloat (hardware that does floating point operations very efficiently) will see a benefit for such processes.

Generally, microcontrollers such as the AVR are single core / single threaded - so while working in a while loop to run the motor controller, you might be lacking resources to do anything else, like navigate a menu efficiently.
Many ARM processors now a days are multi core / multi threaded, meaning that you can have one thread working your print, while another is free for whatever else the user may want to do.
i.e. Any AVR processor running a local webserver to allow remote access to the printer would be painfully basic, where ARM would generally allow for much more flexibility.

Note that if a firmware does not use good multithreaded code, the overhead from inter-thread and inter-process communication may be extremely high.

Don't confuse the multi-core high performance applications processors with the real-time optimised M-class processors. Yes, there are dual core Cortex-M with impressive performance, but they're not multi-threaded.

AVR processor has sufficient performance for standard printing. But it lacks performance for

delta printers (see hexafraction answer)
display menu (it's terribly slow on my RepRap printer which uses ATmega2560)
web interface (ethernet)

Comparison of technical specs should be self explaining. This particular ARM CPU is at least 10x faster opposite to ATmega2560:
CPU ARM-Cortex M3 LPC1769 (used in Smoothieboard)

CPU: Cortex-M3, 1 core
architecture: ARMv7-M (32-bit)
frequency: 96-120 Mhz
memory

Flash: 512 kB
RAM: 64 kB

Microcontroller ATmega2560

architecture: 8-bit
frequency: 16 MHz
memory

flash Memory 256 KB of which 8 KB used by bootloader
SRAM: 8 KB
EEPROM: 4 KB

AVR processors are 8 bit - thus they can only fetch data from memory 8 bits at a time - while an ARM is 32 bit and can fetch data 32 bits at a time. Position resolution requires a 24 bit value minimum - this means the AVR takes 3 data fetches for the position - whereas the ARM takes 1 data fetch.
Worse still, AVR processors internally divide the clock by 3, so that a 40 MHz AVR is running at 13.3 MHz typically, while an ARM is 1 clock cycle per bus transaction and instruction processing - this includes a 32 bit by 32 bit multiple in 1 clock cycle.
The memory map on ARM processors is 32 bit wide or 4 GB while 8 bit processors only have an address bus of 16 bits or 64 KB - which means that bank switching comes into play on any program over 64 KB - this takes instructions and time to be done - while with the ARM this is not an issue.
The cost aspects is about the same as AVRs - it just requires redesigned firmware.
As for FPGAs:

They cost the same or more than the processor
They are fast, specialized, devices and can be configured for specialized task
They have additional cost factors:

lots more decoupling caps are needed because of the speed of the circuits in the FPGA.
Require additional power supplies, and ground planes and power plans - which tends to mean (and require) a minimum of a 4 layer board, or possibly 6 layers, which adds to the cost of the electronics

The result of adding a FPGA to a AVR will cost a lot more than going to a more powerful ARM processor.

Hi and welcome to SE.3DPrinting! Your answer could benefit a lot from correct capitalization, layout improvement and correct use of memory size. Please update the answer.

Hi James and many thanks for your very interesting and informative answer. However, I would agree with 0scar... correct capitalisation, consistent use of the correct SI units (i.e. MHz, GB, KB, etc.) would drastically improve the readability of your answer, as would a reduction of the use of multiple dashes (- - and - - - -) which are rather distracting, tbh.


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Dimension SST Printer Broken parts
My company has an old Dimension SST printer that is out of commission due to a few broken pieces.
I have contacted the Stratsys folk and they won't do anything until we purchase a multi-thousand dollar service policy.
I also have a Makerbot that I can use to create spare parts however, can't find pictures of the original configuration.
The broken pieces are the Toggle Bar and Z Foam Sensor and whatever parts used to hold them in place on the head. Toggle Bar circled in red  View of my printer where the toggle bar used to be
Two Questions:
Does anyone know of a location to purchase spare parts?
Does anyone have detailed pictures (360 view) of the print head they are willing to share so I can recreate the parts/attachments.
Thank you so much for any help!

Does this PDF, page 61 help?

Unfortunately i need the backside view of that image. Thank you for doing some digging!

Seeing as how no one has been able to find a solution yet and I'm not familiar with your machine, I would recommend reverse engineering the part to the best of your abilities. If you don't have the right tools, try finding a local machine shop and ask if you can use their measuring equipment. Sometimes you might get lucky and they will have something more intuitive than callipers, such as a CNC CMM or CMM Arm. As far as acquiring the part, try asking the machine shop if they can produce it, or get it 3D printed via 3D Hubs, MakeXYZ, or some other peer printing service.
I'm sorry I don't have a more direct solution, but hopefully it at least a general sense of what options you may have.

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Printing a CV joint
Fair warning: I am a complete novice in 3-D printing. This will, hopefully, be the first thing I've ever printed.
I want to make a Constant Velocity Joint for a camera stabilizer I'm making. I've been looking at different options, and it seems that a double cardan joint would be easiest to design/make/print. However, the intended use involves force being applied along the shaft, into the joint, which I think in a double cardan will cause "buckling" (forcing the joint into a 90° zig-zag).
Also, perhaps I'm wrong, but I don't see it rotating very smoothly (pretty essential for camera stabilization.)
So my next idea is a Tracta type, with bearings. The question is:
Can you print bearings inside their housing? or do movable parts have to be printed separately?

A couple questions... Are you printing this yourself? What type of 3D printing are you hoping to accomplish this with? These questions could determine your answer. As it stands, it depends. Great first post, it helps to have the background of what you're trying to accomplish! Welcome to 3D Printing!

Thanks! I'm planning on using one of my school's printers: they have quite a few, but the less expensive ones are a "Makerbot/Rostock FDM" and a "ZPrinter 450 Powder." So in the sense that I would like to design and "hit print" myself, yes I am printing this myself.

There's a nice video of printing a ball bearing in one pass (race, balls, everything) at https://www.youtube.com/watch?v=Es-2BNpCtjU.

Here are some uni lab blog entries from 2017 that report on a 3D-printed Tracta joint: https://additive-mfg.me.wisc.edu/?cat=63

Based on information provided in the comments I can say that yes, you can technically print bearings inside their housing. However, you must consider the capabilities of the technology.
Typically an FDM printer, such as a MakerBot Replicator, can yield undesirable results depending on how small you need the objects and how close each object is to another (ie bearings to the housing/each other). If you have a dual-extruding FDM printer, you could utilize a second support structure material. For example, you could print the bearings/housing in PLA and print the raft/supports using water soluble PVA. This provides a solid structure while printing without worry of having excess material in the housing (defeating the purpose of a bearing).
On the other hand, using the powder printer is most likely your best solution for creating the bearings (and less frustrating). Naturally, you will not need to worry about support structures as there is support inherently created as the powder is lain out for each layer. You just need to be sure that the tolerance of your model adhere to the capabilities of this machine and its post-processing.
Regardless of which technology you use, be sure that your design incorporates a means of allowing support material to be taken out after the print is complete.

"you will not need to worry about support structures" this is only true with binder jet printers, which are a very specific type of powder printer (and not well suited to mechanical parts). I work with an SLM tool at work, and support structures are one of the biggest challenges. With metal SLM, you will get internal stress caused by thermal gradients that cause steep overhangs to curl upwards and crash the recoater. With polymers, the accumulated heat will cause sagging under gravity without support. With either if there is no support at all, the recoater will drag the part away.

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How to upload my works to Thingiverse without making my real name public
I want to upload some of my works to Thingiverse without making my real name public (displaying it on the profile page).
I think it is OK to register my name to the site unless the make it public, and it is required by the terms to provide truthful and accurate information.
I tried creating an account on the site, but I deleted it because I couldn't find the way to hide my name (set another one) from the profile page in a short time.
I see some accounts that doesn't seem showing their real name (for example, their name on profile equals to their account ID, or at least not in two parts: first and last name as required on registration), so I guess this is archivable.
examples:

http://www.thingiverse.com/Darkcheops/about
http://www.thingiverse.com/ruaridh/about
https://www.thingiverse.com/Torleif/about

How can I set my name for profile page on Thingiverse after registration and logging in?

Maybe I should use YouMagine or makershop.co, which don't seem asking my first & last name, to share my works.

To change your displayed name (as opposed to username) in Thingiverse:

Go to your profile page
Click "Edit Profile" on the info column on the left
At the top, next to "Thingiverse Settings" is another link/tab called "Makerbot Settings". Click that.
Change the First Name and Last Name fields, and save.

Note that neither First nor Last Name is required; if neither is provided, your username will be displayed in place of your display name.

Thanks, it worked! I thought making them blank is impossible because they said First & Last names are required on registration.

I joined this community just to +1.  It makes sense that Makebot would put this setting into a place that people least expect, since the company is not exactly integral to the community anymore.

If editing, beware that true anonymity is achieved: your public profile will have been indexed by Google etc, and the case of Google can be revealed by "View Cached Page" in their search results.

You can put whatever name you want in when you make an account - You decide what your name is, people go by pseudonyms in 'real life' all the time, this is perfectly acceptable. There are actually very few places where you have a legal obligation to provide your name as it appears on your birth certificate. Opening a Thingiverse account is not one of them.
To answer the other part of your question, yes, it is possible to change the name displayed after you have created your account. I would be surprised if they bother to actually keep an archive of past names though.

Yes, but the point of his question is it's totally non-intuitive where to locate this setting. It's "hidden" under "Makerbot settings", a place I would never ever look since I do not have a Makerbot device.


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Autodesk Spark Print Manager Operating Systems?
What operating systems are available for running the Autodesk Spark Print Manager? (https://spark.autodesk.com/developers/reference/printer-manufacturers/integrate-your-printer/integrate-your-printer-model)
I'm finding the documentation a little difficult to parse. It does seem that there are only build options for Windows or Mac, but I want to confirm.
Thanks!

What exactly does that software do?  It wants me to make an account to see the documentation?  It it like octoprint?

Hey! Sorry for late reply... Basically it allows you to manage print queues, prepare basic DLP/FDM jobs, among other things. Kind of like the glue between a GUI and the firmware of the printer.

I checked https://spark.autodesk.com/developers/reference/desktop-applications/print-manager. It seems that Print manager is a application written in JavaScript and its source code is available on github.
So you have to install node.js to run it. So you can use all major OS (win, mac, linux, ...).


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What is the best length of the melting zone in the hotend?
There are many hot end designs out thee and one difference is the length of the melting zone.
The melting zone is that part of the hotend where the pushed in filament is heated up and therefore starts to melt. Is it better to have a short melting zone, or a long melting zone? What are advantages of each solution. And are there materials that benefit from a short/long melting one more than others?

Short melting zone melts material in small amounts which is suitable for thin layers with small nozzles. In opposite, long melting zone can heat a big amount of filament which is needed for fast printing and thick layers.
short melting zone

less amount of melted material
thin layer heights
quality printing with details
give more precise volume control with less flow/pressure lag and better retraction performance (thx @Ryan-Carlyle)
nozzles: 0.25-0.8 mm (available for E3Dv6)

long melting zone

more amount of melted material
thick layer heights
fast printing with less details
nozzles: 0.4-1.2 mm (available for E3D Volcano)

Example
Example of those hotends are E3Dv6 and E3D Volcano
E3Dv6

E3D Volcano with a much longer melt zone than v6

Speed comparison video:

Speed comparison graph:

Update
CNC Kitchen YouTube channel did a review of 0.1 mm nozzle, where the author discusses problems with very low material flow. The main point is the usage of high-quality materials (he uses Polymaker PolyMax PLA) and avoiding materials like PVA, which tend to crystalize under heat.

Should also mention that short melt zones give more precise volume control with less flow/pressure lag and better retraction performance.

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Gnarly filament: just one of those things, or grounds for complaint?
everyone.
I'm a relative newcomer to 3D printing, so I don't know what constitutes an unacceptably bad spool of filament.
About 1/6 of the way into a roll of PETG (and maybe 4 hours into a 6-hour print), an over/under wrap brought things to a screeching halt. I aborted the print, then snipped the filament and started unspooling it, looking for more cross-wraps. I found a ton of them, along with a ton of kinks.
I stopped about 1/3 of the way into the spool, still finding kinks and cross-wraps, and said to heck with it. The only way to use it would have been to run the entire length onto another spool, carefully avoiding cross-wraps, and hope the kinks wouldn't affect the print quality.
I complained to the supplier but never even got a reply, so now I'm wondering if this is just one of those things I can expect from time to time. Any thoughts & opinions would be much appreciated.
Cheers,
Glasseyed

Filament should come off of the roll without overlapping itself.  That being said depending on what you paid for it would determine if you should complain.  Normally you get what you pay for.  If you paid \$10 for it, I would think that is why it was so cheap, but if you paid >\$25 it should be nice stuff.

I paid $35 CAD per kg, so it's not ultra-premium or bargain-basement stuff. The fact is I've been quite pleased with the other filaments I've bought from this supplier, but the lack of response to my complaint made me determined not to buy from them again...until I got to wondering if this kind of thing is only to be expected every now & then.

I would go and complain.  Worst case is that nothing happens, best case is you get new filament (and get to keep the bad roll too).

@Glasseyed It could be just a fluke thing, but you should contact your supplier for this sort of thing (so long as it is not user error). You're paying for their standard quality, if you're not getting that, you deserve either a replacement or a refund.

Sorry to say it, but MOST wrap-unders are caused by end-users releasing the free end of the filament when handling the spool. It is mathematically impossible to introduce a knot during initial spooling, and all the reputable filament vendors these days have pretty careful free-end control when the spool is taken off the spooler and sent to packaging.
Where you may get knots straight from the filament vendor is if they're respooling very carelessly and let go of the free end. You should only see this with very cheap filament.
So, it's possible that your vendor messed up, but you should probably rule out your own handling practices first. It's not hard to prevent losing the free end. The nicer spool styles these days have holes on the side-flanges for securing the free end during handling/storage. Or you can print one of many, many filament clip designs from Thingiverse or your favorite model site.
If you're very careful with handling and still get knots, switch suppliers. Anyone sloppy enough to repeatedly mis-handle new spools is likely also using extremely cheap material, and there have been a lot of anecdotal reports of very nasty industrial chemicals being mixed into the colorants of low-cost filament.

Thanks, but user error wasn't responsible in this case: not only were there lots of other crossovers deeper into the spool, the filament was wobbly/kinky in a way that suggests problems with the take-up mechanism at the factory.

Crossovers very often work their way down as the spool unwraps. A knot can slip and slip and slip for hours and then catch and wreck the print. Not sure what you mean by wobbly/kinky?

As if someone had flexed the filament every couple of inches, putting a slight bend in it. Probably nothing too serious by itself, but it tends to reinforce my belief that there was a problem with the take-up mechanism. As I said in my comment to Eric Johnson, I've been quite pleased with the other stuff I've bought from them. Maybe I'll just re-spool the remainder when I have an empty spool kicking around ( did I mention I'm a relative newcomer? ;-) Cheers!

Little wobbles can happen as the warm filament rolls over previous wraps and jumps from groove to groove. Bigger bends might mean they re-spooled off a drum that had a core that was too tight. Hard to say.

Knot happens when you loosen the filament yourself and then leave it like that or try to manually re-spool it.
To avoid this kind of situation as well as the curly filament coming off the spool and getting tangled there, try to not loosen it and also build or print a "spool guide" for your 3d printer: http://www.thingiverse.com/search/page:1?q=filament+spool+guide&sa=


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How to create a web-based PHP that can print to multiple printer(when idle) using silent printing
The print job connect to the database. When there is an idle printer, the print job directly goes to it. It need to connect with print server too.
How do i start? Can someone help me...
Thank you.

Hi, Adia. You question is very broad in it's current state, as often is the case when you don't know where to start looking for answers. It seems, however, that you are looking for a way to set up an automated printer farm. You might want to focus your question on that.

Something like this: https://github.com/Hoektronics/BotQueue   ?

@Aida_athny, I am flagging this question for being too broad, which could lead to it being closed. You may choose to edit your question to become more specific, and then ask for it to be reopened, should this happen. Please have a look at the following link for a general guidance on how to ask a good question: http://stackoverflow.com/help/how-to-ask

I'd recommend starting with connecting your printer(s) to OctoPi. From there, try to find either an API or way to create your own plugin. Then just set up a workstation that will manage your print queue and delegate the prints using some form of web request.
I personally don't recommend creating your own slicing engine. If you want to do everything directly from "the workstation" try looking into Skeinforge (most popular from ReplicatorG slicer), Cura (I believe from Ultimaker), and/or Miracle Grue (from MakerWare) as your slicing engine. You can most documentation/source on GitHub.
In the meantime, try to narrow down the general sense of how you want to accomplish this and edit your question. As a reminder for more technical questions regarding code, please use Stack Overflow. For example, "How to create/use REST request?"

+1 for mentioning OctoPi! From the rather vague question, that is a much more relevant solution than just saying "learn programming, then do this or that" in general. :)


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How small can I expect FDM 3d printers to print?
I  was wondering if this printer(daVinci 1.0) had the ability to print very small objects, like insects, coins, or small nuts. (About the size of 1 -2 cubic centimeters)
Here is a link to the printer on the website.
The reason I ask is someone asked me if it was able to, but I have not been able to access the actual 3-D printer for use at this time, just manuals which I have looked through.
So if the 3-D printer was able to print small objects, would a novice be able to do such a thing?
Please let me know if any additional details are needed.

I'd suggest to edit your question title to "How small can I expect FDM 3d printers to print" since the answers are the same for almost all of them and it would be easier for others searching for that question to find. You can still mention that you personally own or are considering a daVinci 1.0 yourself.

1) If we're talking about FFF/FDM printers:
Accuracy of the electronics and motors allows it, yes.
But how FDM printers work it might be very hard to lay down layers of molten plastic so small as to preserve little details in the X and Y axis, not much of a problem doing 20 micron layer height though (Z resolution).
Check this answer to find out what the X and Y resolution is and what it depends on: https://3dprinting.stackexchange.com/a/509/381
You'll need both a small enough nozzle, as well as somehow cool the plastic because since the printed objects are so tiny the nozzle keeps contact with the surface surrounding it and heats it longer, which might melt the whole object or even char it.
I've seen very few people do tiny prints with success. And the smallest nozzles I know are 250 micron.
Not trying to dscourage you, just letting you know. If it was easy to do I think more people would be doing it and more companies would be advertising their printers as capable of such a thing
So you'll have around 20 micron Z resolution and around maybe 200 in the X/Y.
If that's enough for you, then you could try. Calibrating it all won't be easy, tiniest backlash will be noticeable.
2) It's a lot easier with curing resin 3d printers (SLA or DLP). Most of them actually have trouble printing larger objects, ironically (trouble sticking to the bed and cracking of the 3d print).
Even here badly calibrated lasers would prevent you from doing this and even many Form 1 users have reported their lasers being assembled poorly resulting in poor beam profile.
Size of the laser beam profile (aka laser "spot size") is what determines the X/Y resolution for SLA 3d printers. With the Form 2 its 140 micron, unless you'll get a badly calibrated printer.
For DLP printers it's easier, it's the resolution of the DLP projector divided from the size of the print area.

Strictly by looking at the technical specifications of an FDM printer, there are a few things to note regarding the maximum print quality you can expect to achieve:

The minimum layer height  - here given to be 0.1 mm
The nozzle diameter  - here given to be 0.4 mm

Minimum layer height:
On a finished print, the minimum layer height will affect how visible the horisontal lines of the print will be. Printing at a lower layer height can dramatically increase the smoothness of the finished part, while equally increasing the printing time - among several other things.
A minimum layer height of 0.1 mm is fairly common for low-cost desktop FDM printers.
Nozzle diameter:
Just like the layer height defines the vertical resolution of a print, the nozzle diameter defines the sharpness of horizontal features of a print.
When printing with a large nozzle diameter, all sharp edges and corners of the model will have a slight roundness to them: the larger the nozzle diameter, the more rounded sharp corners will be, and vice versa. You might think of it as making a detailed drawing with a blunt pencil.
A nozzle diameter of 0.4 mm can perhaps be considered the standard for desktop FDM printers today, and will allow you to print "fairly accurate" parts.
Will the daVinci work for you?
Since I've never worked with the daVinci printer before, I cannot make a statement on it's user friendliness, or actual performance.
In general, if you intend to use it to print fragile, complex models such as insects, I believe a resin based printer might be more right for you, since they typically will allow for much higher reproduction of details than FDM printers. Printing solid/compact structures like coins and nuts, on the other hand, can typically be handled by a well calibrated FDM printer.

Also worth mentioning is the issue with printing supports and overhangs at such small sizes. And not familiar with daVinci, but even if the software/firmware limits the minimum layer height to 100 microns (0.1mm) it might be possible to hack the firmware or replace the motherboard to go down to 20 microns (maybe hacking is not even needed and it's more open).

@LeoErvin, just like you say in your answer, FDM printers really struggle with printing tiny objects. I don't think I will go into all the details why in my answer right now, since that would be a question of it's own!

So lets say I have already purchased said FDM printer. What can I do to ensure a "good" print? Should I (can I even?) get a better nozzle, is this something a layman can do? Or should I instead just use what I have?

@RoSiv I'm pretty sure you can just install a better/smaller nozzle and just update your slicing engine settings to reflect the changes.

@tmb0115         Would you have any specific recommendations for how to go about that given the information I provided? I am terrible at technology and a novice at best. Explaining it to me like I was five might be apropos.


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Is it possible to use an aftermarket controller on a MakerBot?
I've got a dead MakerBot Replicator Dual and I'm not really interested in fixing it with about half the parts being proprietary, discontinued, and therefore very expensive. So, I'm wondering if it's possible to use a controller board used on some of the other RepRap machines.
I'd assume that it's all relatively the same, mostly need a means of routing/regulating power to the servos/fans/etc. based on a g-code. If that's true, then I'm also assuming the next step is ensuring the slicing engine spits out the right format for the board (.s3g, .x3g, .gcode, etc.) and that the slicing engine knows the proper bounds for the machine.
Side question, if I used an another controller board, would I be able to still run MakerWare/MakerBot Desktop? So far, I've preferred the MiracleGrue slicer, but I've used Cura on Octopi and it'd suffice.

You can put pretty much any controller in pretty much any printer, with a few noteworthy details you need to keep in mind for a Replicator 1.

Makerbots use thermocouples. Most RepRap style 3d printers use thermistors. So you would need to replace the extruder temp sensors, or choose a new controller with thermocouple support.
Makerbots use 24v heaters and fans and PSUs. Most RepRap style 3d printers run on 12v (although this is slowly changing because 24v is better for performance and safety.) You can either pick a new controller that is known to be compatible with 24v, or replace all 24v-rated components with equivalent 12v-rated components.
The existing heatbed thermistor circuit is probably not the same kind of circuit that your new controller will expect. Older Makerbots use a small voltage divider circuit on the HBP PCB to convert the thermistor resistance to a voltage signal, whereas RepRap style controllers typically have this circuit on the mainboard and thus need only a simple thermistor hookup. You could add a new thermistor, or modify the existing circuit, or get an entirely new heatbed.
The existing endstops are full +5v,GND,Signal style mechanical switches with debounce capacitors and LED indicators. These should be compatible with most controller boards given proper firmware setting, but you may need to do some creative wiring if there isn't a suitable three-pin endstop port on your chosen board.
The LCD and 5-button panel will not work with other boards. You'll need to replace that or just run a remote host via USB.
Connectors may be different, of course. That's always an issue with any board swap.
You will need to export RepRap style gcode instead of .x3g files. Makerware/Desktop can export gcode but there may be some minor differences in Mcode assignments from what most RepRap style firmware will expect. I couldn't tell you offhand whether this will work, but to be safe, it would probably be best to use a more traditional RepRap slicer (Slic3r, Cura) or Simplify3D.

So that's a healthy to-do list. At a certain point you're practically building a new printer. But there is a significantly easier approach than installing a RepRap style controller: replace the dead Makerbot Mightyboard with a compatible community-designed Sailfish board like the Azteeg x3 by Panucatt or new CloneBoard Mini by Carl Raffle. Or, if you're ok with Chinese sourcing, a FlashForge Mightyboard will be a near 100% drop-fit replacement for your Makerbot Mightyboard. Any of these options will give you fresh new electronics with minimal hardware changes in the rest of the printer.
Either way is fine and you'll end up with a working printer. Using another Sailfish board will certainly be easier, if you don't object to staying within the Sailfish/x3g toolchain and Makerbot/Clone parts ecosystem. Makerbot does have a very bad community reputation these days, but it's important to remember that the Replicator 1 Dual is a completely open-source machine from the "pre-evil" days, and compatible spare parts are widely available from literally dozens of vendors. The Rep1-derived Makerbots and Clones collectively comprise the most popular single "flavor" of 3d printer in the world (totaling as much as perhaps a quarter of all consumer/hobbyist 3d printers sold to date) and many/most of the spare parts for Replicator 2/2x's and clones will also fit in a genuine Rep1.

+1 for such detail, thank you very much! I've been discouraged from replacing some of the MakerBot components (ie servo drivers are flipped technically from A4988) and of course the famous exploding MightyBoard (the second time my machine has died from it). But, your details at least give me a better direction to start reviving the machine. Thanks again!

Are your boards failing because of the 5v regulator blowing? That's the usual issue with Rep1 boards. The alternate versions I mentioned don't have that problem. There's also a recommended mod to replace the 5v regulator for all still-working Rep1 Mightyboards if you end up getting another one.

I tried replacing the regulator post-issue, but there appears to be damage elsewhere on the board. I posted a question verifying the process earlier on this site.

Once the 5v regulator goes, 99.9% of the time the whole board is dead. It dumps 24v into the 5v logic rail and most of the chips are toast.

Sorry, to answer your question earlier, yes the board died due to the regulator. When powered on, the servo drivers lit up, but nothing else. After replacing the regulator, the whole board showed signs of life, but the LCD screen shows two black lines. Idk if that means the LCD needs to be replaced as well though. If I get a new controller, I'll post whether or not the LCD had to be replaced.

Two solid lines typically means the firmware isn't talking to the LCD. Which  is usually caused by the wrong firmware rev loaded (eg load Atmega 2560 FlashForge build on an original Atmega 1280) or -- more likely in this case -- the main processor being fried. How do you feel about soldering big SMD chips? If you have a hot air rework station, you could replace the processor for a few bucks.

I'd feel fine doing it if I had the right tools. It's definitely a hardware issue since I already tried connecting to the computer to reset the firmware. You've given me a lot of options to look more into. I'll probably go over the replacement board options and get back to trying to fix the dead boards later. If/when I get to that point I'll definitely post my results on the site here. Thank you again for your help!

Does it show up on the computer when you connect USB? That will tell you whether the USB chip is fried too. If that's fried, you'll need an AVR programmer to manually flash the replacement processor because the standard firmware upload won't work. (Yes, this all gets somewhat complicated.)

No, it didn't show up in the device manager. Yeah, I've read about some of the home made machines going through this process lol I just don't have all of the tools to do a lot of the more involved work on electronics... Yet :)


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How to make your own 3D printer?
I am wondering if I can get some electronic and mechanical layout of the machine.
Is it possible to make 3D printer components with 3D printer?

-1 as your question is too broad in its current state. Please show that you have at least done some research that can narrow your focus.

Look at the RepRap Project

Yes, look at http://reprap.org for a project that's been doing what you're asking about for about a decade now.


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What kind of filter do I need for the enclosure of a 3d printer?
I've heard alot about the need for ventilation when using 3D Printers lately.  Is there any special sort of filter that would prevent the toxic gases from leaking out of the printer while it's printing it's filament?  Is printing outside a solution while I build an enclosure?

For the most part, a consumer 3D Printer will only need proper ventilation when using potentially harmful materials such as ABS. (See duplicate question). If you're printing with primarily PLA, then you don't need to worry. I print mostly with ABS and keep my machine close to a window and I haven't experienced any issues.


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What is the cheapest 3D printer that you can get right now?
What is the cheapest (desktop) 3D printer that you can get right now?
Is there a current price list (with different vendors)?

Voting to close as off topic. Suggestions for purchasing printers should not be asked on this site.

Perhaps it would be best to repost the question asking for ROI comparison of marketed printers, instead of which printer to purchase?

@tbm0115 I don't think so. Printer comparisons inevitably become outdated with new models coming to market.

@TomvanderZanden True. Is there at least another site we can refer OP to?

The peer-based 3D printing service called 3D Hubs conducted a survey of its users and which printers they use and suggest. This survey's results are here.
I recall a similar Google Group conducting a similar survey a year or so ago, I'll search for the link to that as well a little later.

Did you manage to find that link to the Google groups survey?

You know it's made by a 3D printing service (who make money by people not having their own printer) by calling a 1000$ delta and the CR-10 "budget" printers.


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Are the Makerbot 5th generation's initial issues resolved
I am considering buying a 3D printer for work (scientific research). On paper, the Makerbot 5th generation seems to be the best option, because the price is right for my budget, and also because I'm generally pretty busy, so I want something that's as close to "plug and play" as reasonably possible. This will be my first 3D printer and I have no prior experience with the technology.
However, any search for "Makerbot" brings up a raft of negative reviews from around the time of the 5th generation's first release, which mostly focus on issues with the smart extruder constantly failing and needing to be replaced under warranty. Many of these reviews point out that this may be an initial "teething" issue which might be fixed in later versions of the model, but now, one year later, I'm unable to find any information about whether this was indeed the case.
So: are the initial issues with the Makerbot 5th generation's smart extruder generally considered resolved, or is it an underlying flaw of the model that won't be fixed until the next generation?
I imagine that people might want to suggest alternative models in the same price range. That would be welcome, but I have an extra constraint, which is that I can only buy models that are available in Japan without a long delivery time - this probably limits my options quite a bit.

After a bit more research, it seems the Zortrax m200 might be a better fit for me - it's in the same price range (actually a fair bit cheaper) and also very "plug and play", but the reviews say it is very reliable and it prints in many more materials, with a heated print bed. So probably I'll go with that one.

As someone with a makerbot, Ultimaker, and 3-4 other printers.. Don't. Get the Ultimaker. It is worth importing.

Makerbot claims the problems are fixed. I have heard from a number of resellers that the problems are fixed. Unfortunately, both of those are somewhat biased sources. It's surprisingly hard to get good info on the subject -- very few credible people are talking about recent experiences with the product line.
Issue #1: The main surviving user forum (https://groups.google.com/forum/#!forum/makerbot-users) has had the torrent of people reporting 5th gen issues more or less dry up. There ARE still people posting issues, but at a fairly low level that is not far outside what you would expect for an average hobbyist printer. What we DON'T know is whether the flood of complaints has slowed because they're working better, or because very few people are actually buying them any more.
Issue #2: The power-users and community leaders that typically evaluate and review 3d printers are all avoiding the 5th gen line like the plague. Makerbot burned up a lot of community good-will by going closed source with the Replicator 2, and lost more good-will through a series of misunderstandings over patent applications and the Thingiverse terms of service (Takerbot scandals), and put the nail in the coffin by knowingly releasing a non-functional 5th gen product line. Very few credible people are willing to give them a chance at this point, so there is a severe shortage of unbiased reviews.
Issue #3: Makerbot has a proven history of buying off journalists and reviewers to get positive 5th gen press. Some verifiable examples:

Hundreds of fake 5-star Amazon reviews from paid review accounts. A relevant analysis: http://www.amazon.com/review/R2JI8LRRXZYNX1/ (Not verified, but related: a widely-believed rumor states that the German Amazon site actually wiped all of Makerbot's 5th Gen reviews because of blatant tampering: http://www.amazon.de/MakerBot-MP05825-Replicator-5th-H%C3%B6he/dp/B0183TP806/)
The CES awards initially given to the 5th Gen line were given before Makerbot had functional firmware. None of the 5th Gens at the CES launch were functional. All demo prints shown were made on Replicator 2s. How could a non-functional product win awards? Not hard to figure that one out.
Historical positive press in the 3DP journalism media (3ders, Make Magazine, etc) has been directly proportional to the volume of ad-buys from Makerbot or the parent company Stratasys.

I could keep going, but you get the idea.
So it's hard to evaluate the reality of the situation. But even IF the Smart Extruder issues are truly all fixed (jams, leveling issues, thermocouple connection, filament encoder failures, etc), there are still meaningful problems with the product line.

The print quality is not impressive. The motion mechanics, which have not been appreciably changed to my knowledge, are not great. The Smart Extruder is basically a giant pendulum wobbling off the side of a non-optimal gantry selection of an H-bot architecture. Makerbot has addressed the floppy construction via firmware tweaks to significantly slow down the machine to give marginally-acceptable print quality. According to most reports I have seen, a Replicator 5th Gen will print significantly slower than a Replicator 2, for example. Expect in the neighborhood of perhaps 30-40% longer print times than comparable printers.
The price tag is roughly double or even triple the current market price for the size and print quality output of the machine. There are so many great printers on the market now for significantly less money that it's kind of nuts to drop the cash on a Makerbot.
It is marketed as a PLA-only machine. That's fine if you're printing art and trinkets, but it's not a great option for mechanical parts. While you CAN print other materials, this is not technically supported.
The support plan structure has quite frankly become abusive. Makerbot used to have really helpful phone tech support, but the crushingly massive volume of 5th gen troubleshooting requests forced them into a paid tech support model. Around the same time, Makerbot shut down their user community forum and deleted links to external technical resources off their website. So unless you know the right places to go, support is scarce. For official tech support you must buy "Makercare" or pay for each help ticket. This is completely out of line with industry norms for a hobbyist/consumer 3d printer. They essentially took their biggest liability -- unreliable printers -- and tried to twist it into a profit center. I personally think this is a significant reason to avoid the company entirely.

Is it possible to get good results from a Replicator 5th Gen? Sure. But it's a poor value for the cost, from a company that has spent the last few years systematically driving away its former loyal user base. I would recommend staying away until there's some significant change in the product line at minimum.

Actually, a reasonable review just came out the day after I wrote this: http://www.computerworld.com/article/3032237/emerging-technology/review-makerbot-replicator-3d-printer-adds-its-new-smart-extruder.html

I got (with no prior experience) a 5th generation model soon after its release and indeed had painful troubles with the extruder and had it replaced under warranty. Firmware from late 2014 on has produced much better results.
It still needs far more work than -- say -- a laser printer, but that might be simply part of the technology.
Overall thus my answer is "yes".
I also just noted this week that Makerbot is about to rebase an improved Extruder+ that claims to further reduce clogging problems.

TL;DR - Save your money and look elsewhere.

We purchased two Replicator 5th generation for use on two different campuses. They were purchased at the same time.
One of the units was defective out of the box and was sent back and replaced. Then the extruders became clogged again and again - on both campuses - through lighter than average use, I would say. We bought two new extruders, after we got as much use as possible out of the originals. Then of course they became useless.
Tech support recommended purchasing the Smart Extruder+ at a premium price, with a promise that this would solve all of our problems. They did for a short while. I must point out that these printers were not under heavy use situations. Now, we have suffered a catastrophic failure with one of the printers. Possibly a power supply issue, or main board. Time will tell...

Realizing this question is somewhat old, I'd like to add an update from the perspective of an owner.
I've used/tested the Smart Extruder+ on my Replicator+ for about a year now and have had great success!
I jumped from a Replicator Dual (balsa wood version) to the Replicator+, so I don't know first hand what the issues were with the original Smart Extruder.
Regardless, here are some of my impressions on the machine's Smart Extruder+:

Swapping material is a breeze
Calibrating the z-offset is much easier with the automatic adjustment (over older machines)
Filament detection has saved me a few times when the filament got kinked or wrapped around the spindle. As well as I'm able to actually fully use a spool of filament now (over older machines)
Temperature control seems to be much more consistent than older machines, but that typically stemmed from motherboard issues in the past
While others may complain about separating extruders based on material type (ie one for PLA, one for Tough PLA, etc.), I find it a great way of ensuring quality. This ensures that there is no "cross-contamination" of materials and the wear on the hardware is a more standard rate.

I do not think the 5th generation is a reliable product. I think you are best going with the older Rep 2 - that printer is by far the best.
Makerbot jumped the ship and released the 5th generation before it was ready due to pressure from the board. Love the Rep 2 - by far the best printer out there. This is because if the extruder gets clogged you can easily fix it. With the 5th generation you will either have to send in the extruder for repairs or buy a new one completely.

I own a 5th gen printer and after teaching myself how to dismantle and clear the smart extruder of jammed filament I can attest to the machine working better than any other 3D printer I have used. I run the 3D printing section at Tampa Hakerspace and the MakerBot is much more reliable than the prusa or wanhao which we use at the space. I had problems with the machine initially but now it works like a champ

You should specify which model you are comparing before stating the relative reliability.  Unless you are impying that a brand is always more reliable than the other, which is demonstrabily not true.

I would state for a fact that my makerbot 5 gen printer is better and eaiser to use than any other at the price I paid., I have used many other types of printers like wanhao, purusa, monoprice, see me cnc, lutz bot. You get whatever printer you want and I will set mine up quicker and make prints faster than you will. Since I can now fix any extruder jams myself I don't have any problems with the printer.

It therefore sounds like your post is a personal opinion/faith in a brand, rather than an objective comparison.


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Using an Arduino Mega with burnt voltage regulator
Due to a not-given compatibility with Makerbot mechanical endstop wiring (and carelessness on my side) I ended up burning the voltage regulator on my Arduino Mega 2560. Now, powering the Arduino separately from a USB power supply, I can operate the electronics, however, I am still unable to receive any signal from the endstops and I don't want to hook up my replacement Arduino until I see that my wiring is correct.
Could I have burnt anything else on either the Arduino (pullup resistors were firmware disabled) or the RAMPS 1.4 which makes it impossible to receive a singal from the endstops?

I just burned up a voltage regulator on a Chinese clone Arduino Mega board powered by RAMPS and my research led me to conclude that it is not uncommon and that the clones may have substandard regulators. If you want to use a Chinese board, one solution I found on another thread was to cut D1 on RAMPS and power the Mega directly with a lower voltage supply (or USB). I am just going to get a genuine Arduino board.

@4redwings - While I most definitively applaud the intention to buy a genuine Arduino and support open knowledge in that way, the question is specifically about the possibility to have toasted something else than the voltage regulator, so yours can't really count as an answer. :)

Have you found and fixed the problem? If so, has the answer below led you to the solution? Please vote to accept the answer so this question is not bumped up once in a while and can be removed from the unanswered question list. You may even add your own solution and accept that after 48 hours! If you have not been able to address the problem please update your question.

Take a look at Ryan's answer to my question. I believe the MightBoard is based on the Mega 2560, so it is possible that some of the other components could have been damaged. If you look at the comments below Ryan's answer, we discussed the possibility of the processor itself being damaged. I had attempted this fix on two different MightBoards and they both ended up turning on, but the firmware wouldn't boot. So, it's safe to say that in my case, the processor on the Arduino was shot.
All and all, I'd recommend not using MakerBot's endstops as they seem to be the main culprit for this issue and has been for years (it happened to me twice since I got my machine in 2012).

I agree, the makerbot endstops are a pain for unexperienced reprap users like I was/am. I already read your thread before, but I didn't dive deep enough into the comments. My Marlin boots up rather regularly on the board and I can navigate the menu on the controller screen without problems, though. Safest bet for now seems to be using just an endstop switch without the board and using both on the new arduino. Is there anything on the RAMPS that could have been burnt as well? I'm not too god in reading electronic circuit diagrams...

I don't think that the results would be as catastrophic as the voltage regulator (mine literally blew up both times), but if the higher voltage managed to leak to some of the more sensitive components, it could damage them. Such components could be the processor, LCD, LED's, etc. In the event of the voltage regulator blowing, I could see how the same sudden surge that destroyed the regulator could leak to the other components before the connection is completely severed. I'm certainly not an electronics expert though.


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What is the MightyBoard 1280 IO used for?
While I've worked on fixing my voltage regulator on my MightyBoard, I've noticed an extra set of pins available labeled Atmega 1280 IO. I've tried finding documentation on what these pin can be used for to no avail. I'm curious if there is any use for them within the scope of MakerBot's Conveyor service or even what sort of functionality with regard to the board itself.
Any links to documentation on this subject would be greatly appreciated.

Do you mean 8U2 IO? There's also 1280 ICSP and 8U2 ICSP. Those are the only non-obvious pin headers on the Mightyboard RevE .brd file.

Or do you mean the big "ATMEGA 1280 IO" section? That's just a bunch of breakout points for diagnostics like all the debug LEDs.

If you check the Mightyboard RevE files on Thingiverse (http://www.thingiverse.com/thing:16058/#files) you will find the schematics and PCB files (.sch and .brd) for the version of the board used in Replicator 1s and (with some minor mods) most clones. The Atmega 1280 IO header section is a bunch of breakout pins for debug functions. There are eight sets of signal/5v/gnd groupings. Four of them are currently driving debug LEDs that show flash codes for particular firmware failure modes. The other four are unused as far as I'm aware.
The ninth and tenth pins shown in the schematic are located on the opposite end of the board, near the 8U2 chip, to give some hacking access to that chip as well. (The 8U2 handles USB comms and firmware flashing the Atmega 1280.)

If desired, you can build your own firmware using these pins for other purposes, such as signaling to external equipment. But building Sailfish is a little more difficult than just running the latest Arduino IDE (for compiler stability reasons) so the vast majority of Mightyboard users never bother modifying their firmware.

I came across the Thingiverse page once and was intrigued with the wording "hacking". I found this very vague. Does this mean you have access to an extra serial IO, way to upload firmware, just more LED " hacks", or something else? I'll double check their Git Hub, as they might have something written in their documentation for Conveyor. Thanks for the info.

I think they're all GPIO pins and thus could be used for most anything you're willing to program except some of the special comms stuff, I think. (There are extra UART and I2C headers for that.) You'd need to cross-reference with the 1280 datasheet to see what kind of pins they are.

Conveyor talks via a pretty dumb USB link to the 8U2, and the 8U2 has a serial link to the Atmega 1280, so I think you'd need to go through the 8U2 chip. But it's possible the extra UART header could be used, I know Jake Borden did some work on that for ethernet control: http://www.extrud3d.com/alt_uart


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Have you used the Retouch3D? What are pros and cons of it?
I teach in a high school that has a MakerBot printer. I was looking at the Retouch3D tool. I'd like to know some pros/cons from people who have used it themselves. Would you say it is worth getting for a high school?

We don't generally do broad pros-and-cons reviews. That type of on-going discussion is just not well-suited to this format. You can read more about how this works here: The Stack Exchange Tour. If you have a very specific question, I'm sure the folks here would love to help, but I have to close this as too broad for this site. Sorry about the confusion.

No confusion. I thought "is this something you'd recommend this product to a school" wasn't broad but I appreciate your feedback. Guess I will have to look elsewhere for this type of question.


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Hictop 3d printer upgrades?
Where can I go to upgrade this printer? It's a hictop prusa i3 3d printer. Where do you buy heated beds suitable for ABS and PLA? Also, what kind of extruder do you guys think I should buy?

This is were I bought it from.
http://www.amazon.com/HICTOP-Desktop-Accuracy-Self-Assembly-Tridimensional/dp/B00N7I1ZVU

I am voting to close this question as it is primarily opinion-based, and purchasing advice is considered off-topic.

I agree with Tom, and has voted for a close.

Also the question has poor detail. We don't have any information on the research the TO has done and what else has to be considered why this question cannot be answered by internet search engines.

Assuming your electronics are open source (such as RAMPS), you can buy upgrades and spare parts from pretty much every 3D printer spare part provider out there, as long as they suit your needs and the specs of your printer.
In other words, if you want make a headbed upgrade, find some bed that i.e.:

Fit the size of your printer
Can be mounted properly
Can be used with your current electronics (and possibly software)

In general, most DIY hobby desktop 3D printers today use more or less the same components mounted in various ways.


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Repeatedly Clogged Printrbot Simple Extruder
I have a Printrbot Simple Metal. The extruder is getting clogged all the time. I went through the process demonstrated here multiple times already. Heatting the extruder and pushing different tools all the way through to make sure it is completely clear.
Every time I get a clear flow of PLA, and after a few minutes the extruder motor starts clicking again. At that point, it is even hard to push in the filament by hand.
I replaced the tip already, but this didn't make any difference. I also tried few different filaments, all of them worked perfectly before.
It feels like stopping the flow even for about 30 seconds would cause it to jam.

Hi, Ron. Could you be using a too long retraction settings? To long retraction can make the hot filament cool down and fasten too far up inside the hotend when either not printing or printing an area with frequent retractions.

@TormodHaugene This happens even with no retraction at all. I just extrude (from the control in OctoPrint) then stop for about 30 seconds and try again and it will be stuck already

Which version of the Ubis hot end do you have? Do you have a fan blowing at the heat sink? Assuming you have a version with a PTFE tube, have you checked the condition of the PTFE tube?

What temperature is your hotend at?

@TomvanderZanden I was experimenting with 195-210C

@RonHarlev Have you tried increasing your hotend temp. A lot of people go as high as 225C

@tbm0115 yes. That was one of the suggestions in the answers below. It didn't solve the problem :(

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?

@tbm0115 I ended up just buying a new hot end :(

I'm sorry to hear that! I might suggest adding your own answer, explaining that your solution was to buy a new hotend and how you came to that conclusion. Just so there is a bit of closure for others with similar issues.

I had a similar issue on my Printrbot Simple Metal. I believe my problem was initially caused by clogged nozzle which I replaced, however the jamming persisted. I can't say for sure that it was acting exactly as you describe but I think it may have been similar. I noticed that the little red insulating sleeve was pushed up higher than it was when I got it from Printrbot. When I lowered this my problem seemed to go away.

I'm not sure if this is particularly the issue for you right now, but I have encountered the tension on my drive gear being too high.
Before I upgraded my extruder to the spring loaded mechanism, my extruder used a Delrin plunger to provide tension against the filament towards the drive gear. This plunger used copper washers to help adjust the tension required. Many people ended up upgrading their assemblies to the spring loaded mechanism as the plunger would either put too much or too little tension against the drive gear. Too little and the filament will not be driven into the hotend. Too much and the filament will grind against the drive gear and the drive gear may begin to "eat" away at the filament (especially when the filament becomes hotter). Obviously, if the drive gear is no longer able to catch on the filament, the nozzle will get clogged.
However, even with a spring mechanism, your tension can become too high. Most of these mechanisms allow you to adjust the tension by tightening/loosening the screw holding down the spring. The "sweet spot" for me is just past when the filament can be successfully driven into the hotend. You can test this if you have control over your extrusion motor by removing the extrusion motor from its mount, leaving the spring mechanism installed on the face of the motor. Then, turn your motor on and try feeding the filament through the mechanism. Starting with no tension on the spring, begin slowly increasing tension by tightening the screw on your mechanism until the drive gear is successfully able to guide the filament through. I might even complete another half turn on the screw to account for varying diameters and plasticity states of the filament as it becomes hot.
Hopefully this helps and please keep us updated on anything else you find.

Thanks for the info. But this is not the issue I have. As I mentioned, the filament will flow just fine, until it has a short while (about 30 seconds) to be idle. Then it will get stuck again

This used to happen to me and my Simple Metal often.
The jam was always caused by one of the following:

Feed rate too high (especially on solid layers or long lines)
Temperature too low
Nozzle pushing into previous layer, causing back pressure
Variance in filament diameter

Personally, I have never printed at 195c. I'm always about 225 or 230.
That may seem high for PLA, but then I have stopped having the issues after slowing the print and raising the temperature from 200.
You want to strike the right balance between speed and temp. The slower the feed rate, the lower you can afford to lower the temperature. I think you should start by raising the temperature to 215 and slightly lowering the feedrate.
Also, I have directed a fan at my extruder motor and filament as it enters the nozzle. Keeps the motor very cool and stops the filament softening too early.
Is there a foreign object blocking the nozzle, or does it seem like the filament isn't heating up enough?

I replaced the nozzle tip with a new one, which didn't help. So it is probably not the problem. I also put a metal object under the detector when the print started, to make sure it is working "in free air" and not pushing into the surface, while I was testing it.
I will try the temp/speed idea and will let you know. Thanks!

Taking the temp to 230 seemed to help at first, as the filament was flowing easier at the first few moments. But then when I stopped the extrusion for a few seconds it got stuck again :(

I actually had a jam yesterday after moving my printer. Long story short, I accidentally reversed the extruder motor connector and pulled out all the filament from the nozzle because the motor was reversed. I didn't notice at first and the nozzle jammed because a small string of plastic was left being charred in the chamber.

I found a solution to my problem, which is very similar to your!
Ok, so first, this clog has nothing to do with the flow rate! speed, retraction, or acceleration!
why? because if it under extrusion or over extrusion, the nozzle would spill more or less filament, but it would not make the extruder clog. To make it clog, there must be something that block the path which make the step driver couldn't push the filament through right? even using your hand.
This problem is call "heat creep", especially if you print small detail things. This is because small details make the filament stay inside the nozzle longer, which the heat eventually make the filament swole up and block the path.
To find out if your problem is cause by "heat creep" or not, try to print something small but tall and print something large overall. If it is heat creep, then the small but tall print would immediately clog your nozzle and make the step driver create click sound. If both print ( small and big ) take the same amount of time to clog your nozzle, then it may not cause by "heat creep".
SO HERE the solution for "heat creep." First and the most important, replace your thermal barrier tube. Second, lower the temperature. Third, check the filament guide components such as the drive gear, bearing, and spring. For example, check the drive gear if it securely screw into the stepper motor. Lastly, check the fan, if it possible, install another fan to cool down the thermal barrier tube. In conclusion, replace your thermal barrier before doing anything else.
I hope this help for you and for many other people!
Alopicaso!

Thanks for info. For flexible filament is this still the advice regarding cooling? IE I read I thought for flexible it is better to turn the fan off?  Having said that I'm having hot end blockages with flexible...


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What types of pigments can be used when making your own filaments?
There are many types of pigments made for paint, food, fabric, cosmetic and finally plastic pigments. I guess we need pigments made for plastic, or at least pigments which won't decompose, burn or lose their properties at the temperatures inside the filament extrusion machines (around 240C).
So what type of pigment are we looking for (does that type have a name?) and where can they be found (off-the-shelf from some specialized paint store or is it a more specialized pigment for plastics which is harder to source)?

The normal way pigment is added to filament (or any other extruded plastic product) is by mixing "masterbatch" pellets containing a high concentration of dye with the raw resin pellets. (https://en.wikipedia.org/wiki/Masterbatch) This is significantly easier and more reliable than trying to mix raw pigments into the plastic -- the likelihood of clumping and other issues is greatly reduced.
You can buy these masterbatch pellets and mix up colors in whatever ratios you want to achieve specific output colors. Just make sure the masterbatch pellet carrier material is compatible with your resin. There are a wide variety of vendors, including ebay.

Did I understand correctly that "masterbatch pellets" are things from the injection molding, etc. field and aren't found elsewhere?

You won't find them at Walmart. Easy enough to get online in small quantities though, since some vendors have started catering to people making filament.

No I mean in what fields are they used? Only the one you mentioned? Online shopping is cool, but if it can be found locally at X that might be a better option sometimes.

I don't know of any uses outside heavy industry. What comes to mind is injection molding, plastic extrusions, and industrial filament manufacture (for 3d printers or plastic welders).


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What and how much does coloring in the filament affect in the print?
Are there general rules on how much a colored filament vs. vanilla filament affects the print results, what is affected and how those values should be changed in the slicer to achieve more similar results between different color/colored vs. pure filament spools?

The upvoted answer is incorrect. https://core.ac.uk/download/pdf/217847052.pdf

At this point in time I don't think there is a need to be concerned with purity of filaments based on pigmentation.
For the most part, variations in filament quality due to coloring should be the least of your concerns compared to some of the other variables such as quality of the pellets, extrusion temperature (when manufactured), cooling rate (after extrusion), handling/storage, etc.
Also, assuming your focused on consumer 3D printer use, the typical hardware components aren't equipped to be accurate enough to make fine adjustments with regard to the quality range driven by filament color. Even if there were capable, accurate extruder(s) installed, I think you would need a well designed feedback loop to ensure that you're reading temperatures along the full extrusion process (drive, melt, extrude, etc).
I believe what you're asking involves more material science expertise, from a design aspect.
However, I believe that the more "color" you have obviously reduces the purity of the material and thusly the material properties can suffer. Such properties as thermal resistance found in PLA and ABS. So theoretically if you have Black filament, you'll want to extrude with a lower temperature than you would with a natural "White" filament. I would think that the necessary difference in temperature would be a few degrees (Celsius). However, there are many other factors, such as moisture and manufacturing techniques that can take precedence over color differences.
My advice, figure out how to "cheaply" analyze your material and ensure you have an accurate temperature feedback loop. If can you do that, you'll be able to drastically change the quality of consumer 3D printing.


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How to build the extruder motor holder for the Kossel Mini
I'm building a Kossel Mini, and I'm stuck on the extruder motor holder.
My Kossel came without instructions, I was given a set of instructions by a friend (the "Kossel Build Guide" by Blomker industries). I also found some instructions on the net. However, my components are different from  those in the build guides.
The question is how these components fit together.
I'm pretty certain the stepper motor should be connected to the big black components (labeled (1) and (4) in the picture). The 4 holes in these components correspond to openings in the stepper motor; and the stepper motors for the vertical carriages, were connected in a similar way to their respective holders.
The round thing, second from the left on the bottom, (labeled (2) in the picture) presumably goes on the axis of the stepper motor. Once again, a similar procedure was needed for the motors that will move the vertical carriages.
The screws on the right, labeled (3), are 1 cm long and 3 mm wide.
The other screws are 2 cm long and 3 mm wide.
The stepper motor is a Wantai Stepper Motor Model 42BYGHW811 .
I have e-mailed the company where I bought my kit and am awaiting their answer. Meanwhile I'm hoping to get some advice here.
Apparently the usual stepper motor for a Kossel Mini is Nema 17. Searching  on "42BYGHW811" I mostly find datasheets. Using "Nema 17 mount" or "Nema 17 mounting screws" as search terms, I find a lot of images with a component like (1). But nothing on how this and the other components should be put together for the motor holder for an extruder for the Kossel Mini.

Searching further, it looks like part of this is for the extruder head: something like this image.

Did you ever get a reply from the vendor? Also, a link to the product page would be very useful.

Have a look at the image provided in this seller's part description. it probably says more than my words could (which would also only rely on images - your parts just looked like I saw them somewhere before).
3D printer parts right hand Bowden Extruder kit set no motor compact extruder aluminum alloy for

There are some more images from all sides when you scroll down the description

Your link has died, unfortunately. If you provide the title (i.e. description) of the item as the link text, it would make it easier for products with dead links to be located afterwards... see my edit to illustrate what I mean.

The extruder is an MK8 derivative, I think.
After a lot of searching, the closest that I could find (with an assembly diagram) is this product which has more or less the same parts as yours (apart from the small black bolt and sleeve - used as the axis - which you don't have): [Improved Version] YOTINO Right Hand MK8 Remote Bowden Extruder Accessories 1.75mm/3mm Filament All Metal Remote Extruder Frame Block for Reprap 3D Printer Kossel Prusa.
These are the parts:

This is the assembly process:

This is the completed extruder:

Also, whilst this is not the same beast, this link shows a detailed assembly which could prove useful as a cross reference: RepRapWiki - Extruder assembly
In addition, w.r.t the Blomker guide, there are a number of versions of the same guide that I've come across in the past:

Kossel Mini Build Guide by Blomker - which has a very different extruder to the MK8
Kossel Mini Build Guide By Sintron - which has a similar MK8 extruder but, rather unfortunately, no assembly details, only the finished article is shown, on page 58


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Triangulation adapted to curvature
I don't know whether this belongs here (where most of the questions appear to be about hardware) or on Math or on Blender (though I've never used Blender).
All of the designs that I've published so far consist of grids of bent ‘rods’, and in most of them the spacing of vertices depends on the rod's local curvature; that's easy enough.  But I think some of these figures would look better as continuous surfaces, and it's not obvious to me how to arrange the vertices efficiently — that is, to triangulate the surface just finely enough that it's accurate to within the printer's resolution.
So: given a surface defined by well-behaved functions x(u,v), y(u,v), z(u,v), is there a standard way to choose vertices in u,v space so that the length of each edge is roughly proportional to the radius of curvature in its direction?

Are you asking in regards to a specific software application? If so, which application are you using?

My designs are mathematical, so I write a new little program for each.

And your little program creates STL, or what?

I use .obj, not that it matters.  This is a question of mathematics, not of file formats or application commands.

This is a very math heavy question that probably belong on the Mathematics SE site.

Okay, I've taken it there.  I thought maybe, given that it seems like a common problem, there's a well known answer whose application (in contrast to its derivation or proof) is not so math-heavy.

@AntonSherwood could you post a link to the math.SE question? (You might be more likely to get an answer there, but that answer is clearly very useful to some members of the 3D printing community too - those who write software in particular.)

Oh, right: https://math.stackexchange.com/questions/1700853/triangulation-of-a-surface-adapted-to-curvature

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?

Sigh, I really don't know where to go with this.

For 3d printing this is not very relevant. The triangles only exist in the File read by the slicer. And there are file-formats that can describe rods without the need to use triangles.
If you create a model in a format that uses triangles than just use enough of them to get your model described fully. (millions of very small triangles) That is probably a waste on part where it has less details, but that just makes the file a bit bigger.
The problem of best print quality doesn't end there.
The slicer looks at the triangfles and creates a 2d image of the intersection of the triangles with the layer hight. It then creates g_COde paths along the lines in this 2d image for every Layer. Using triangles to describe the model will only give small line segments for these 2d slices. Therefore the G-Code creates will only have straight line movements (G0, G1).
With a format that can describe curves, the slicer could end up with circles and arcs on the 2d slice and could then use G2 and G3 moves. And if the Firmware of your printer understands these commands you would get the best possible quality with rather small model files.

Yes, well, Shapeways limits input files to 1 million triangles (or vertices? I forget, can't find it now).

They probably do this because their printer will not be able to create better quality. It makes no sense to have triangle so small that the tolerances of the printer are bigger. So with the given tolerances and the build volume you end up with a max number of triangles If they limit it below that then what they do is wrong.

Shapeways also does some pre-checking of the design for topology and thinness.  Likely there's a number of facets beyond which that's hard to do efficiently.


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Scan to vector?
I have some design diagrams only on paper. Scanning them to bitmaps is easy, but I've had no luck getting useful vectors out of them. I've tried vectorizers in programs like gimp, and a few online services. Generally, I end up with enormous numbers of spurious vectors (from dust, dotted lines, text on the  diagram, slightly variations in scanning contrast, etc).
What tools and/or techniques can I use to get a more useful vector result, that I can then modify in a normal CAD tool without spending absurd amounts of time cleaning it all up first?

There is the capable but somewhat expensive Scan2CAD.
Otherwise, if you're happy with outlines and not centre lines, scan b&w, aggressively clean up macules, mask off text, and then vectorize in potrace, autotrace, etc. Alternatively, load the bitmap at the correct resolution into a drawing package as a raster layer and draw the lines/objects you want over it. This avoids the horrors of dotted lines.
Both ways are quite a bit of work, sadly.

I would recommend using something like Paint.NET to "fix" the images before attempting to convert them to CAD.
To my knowledge, most of the Image-to-CAD applications are going to use the grayscale intensity of each pixel to get the Z-axis value. So, you can help this process by pre-filtering the image into grayscale and playing with the contrast until you get enough distinction between the features you want to stand out in your CAD model or print. Here's a quick example using a sample image:
Poor Contrast

Better Contrast

Whichever program you use will generally have an easier time detecting the edges of the flower pedals in the second image the further towards the center it goes.
GIMP has greyscale and contrast tools as well.

I used Corel Draw with good results in professional setting. It's not a breeze - first you clean up the bitmap as well as you can in a bitmap editing program like Photoshop or Gimp - use gradient tool to make the brightness of background roughly even across the entire image, then 'curves' to enhance content and white-out backgrounds, then you import it to Corel and tweak the vectorization settings to produce actual vector borders for the lines (as opposed to tracing edges of individual pixels on one end of the scale, or cutting corners and turning circles into octagons on the other end.) Once you have the image vectorized, you still need to delete all the "floaters" manually - dust specks and so on. The results though can be "good enough for production".

My pictures are saved in PDF. I have used the AutoDWG conversion tool before. It's very awesome. You can try their free online conversion service first. You don't need to download and install, you don't need to register, you can directly convert the PDF in your hand into dwg or dxf, which is very convenient. If the conversion result is not ideal, then download and install the offline version of the software, which is more powerful on raster pdf and can obtain more free conversion opportunities.


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How to cut OpenBeam/MakerBeam?
I'm building a 3D printer and I've been looking around for materials suitable to make the frame.
I have occasional access to a laser cutter which I could use to manufacture a ply box-type (UltiMaker) enclosure, but I like the ease of adjustment provided by the T-slot beam kits.
I don't have any metal-cutting machine tools. Can aluminium beam be cut by hand with a hacksaw to a good degree of accuracy? How does one finish the cut end?

Aluminum of almost every grade is very easy to cut with a hacksaw. I would suggest to mark clearly the cut line and to wrap masking tape at the edge of the cut. Consider to allow for about 2-3 millimeters (1/16") extra material for final finishing. Cut across the line, rotate the part ninety degrees and cut again. Once you have the guide cuts in place, you should be able to manage a square cut by following those guides
You will want to have a clamping mechanism available, such as a vise or workbench type device.
After the cut is done, use a sharp file to make final adjustments to the length and appearance. Push the file, do not drag it backwards. Push forward, lift away from the work piece as you return, then push again. Pick up a file card, which is a fine metal-tooth brush used to clear the teeth of the file.
It is very easy to remove material with a hand file, perhaps three or four strokes to remove 1/16".
Your accuracy will depend on the measurement of the lines you create and how carefully you file to the edge of those lines.

You might also consider a miter box. I've used one for cutting Al extrusion angles and it works pretty well even with a hacksaw.

I have a power miter saw and completely forgot that option or as you suggested, the manual-use miter box. Most carbide tip blades will cut aluminum as cleanly as a laser might.

As an alternative solution, Misumi sells extrusions precision-cut to length for a very reasonable price. You'll get better quality ends and a more precisely square frame from Misumi than if you try to cut them yourself. The HFS-5 series of 2020 is perfect for 3D printers.

I started to build with wood and then switched to T-extrusions -- very glad I switched. The aluminum is quite nice to work with. The extrusions are quite easy to cut, drill, file, etc. -- a hacksaw should be fine, though I often use a cutoff wheel on a "Rotozip" (basically an oversize Dremel).
Just a couple caveats:

Think about which extrusions need to be exactly the same length as which others, and use extra care on those. For example, you might have 2 or 4 supports with plates screwed into the ends, and the plates need to be parallel. You'll probably want to cut the supports all a hair long, then clamp them together and file them all at once.
Extrusions from different companies may differ slightly for the same nominal size. I found that the drop-in nuts that fit my first rails, didn't quite fit the additional ones I bought from another seller later. Also, the center core took a different tap size when tapping the ends.
Be sure to get at least some drop-in nuts. Plain square nuts are a little cheaper, but it's a pain to disassemble anything to get a nut in when you want to add a bracket or fan or cable guide or something later.

-s

Misumi does provide a nice product but it's quite clear their business model is geared toward businesses and not the individual consumer.
The 2020 extrusion seems to be a bear to get parts for, specifically T-nuts and braces.  Openbeam or Makerbeam might be better options and are readily available on Amazon for very decent prices.

Hi, Brad, and welcome to 3D Printing SE! I am not if I understand how this answers the OPs question. Could your please elaborate?


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Slic3r - Can I add new infill patterns?
Slic3r comes with a handful of infill patterns/algorithms, including Rectilinear, Hexagon, 3D Hexagon, Concentric, and Hilbert Curve.
Are there any patterns/algorithms already made and available that I can add to Slic3r? If so, how can I add them in?

Although the core of Slic3r is written in C++ a lot of other components such as infill generation are written in Perl. Since Slic3r is open source there is nothing stopping you from writing your own infill module in Perl and recompiling your own version of Slic3r.
If your considering doing this you can find the existing infill code in the Github repository at
https://github.com/alexrj/Slic3r/tree/master/lib/Slic3r/Fill
Instructions on how to run from source can be found at
http://slic3r.org/download
Here is a commit where a new infill pattern is added. This should show you all the parts of the codebase that must be modified to add a new infill model (some trivial C++ modifications appear to be necessary in addition to the Perl code)
https://github.com/alexrj/Slic3r/commit/2811af349ae17230a525ddcf819b1ddffaa250c9


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Getting rid of hardware parts smell (GT2 timing belt)
I ordered 10m of GT2 timing belt for a printer I want to build, however, the chemical smell from the belt is completely unbearable, in the sense of it gives me the feeling it is destroying something in my nose (and my nose isn't even particularly good). I tried to leave the belt outside in my garage for about three weeks now, but the smell has gone only so much. I naively assume it is the chemical to make the belt soft and bendable, would that even be a health risk having the belt around me for more extended intervals of time? Can I make the smell go away, and what would be the best way to do so?

It's a garbage-quality belt, and it will probably continue outgassing at a steadily-decreasing rate for a very long time.
The fact that it has a strong chemical smell is pretty good evidence that it would not comply with regulations in civilized countries (such as REACH). I would recommend returning it or throwing it away and buying from a more reputable vendor. A large fraction of all cheap 3d printer parts these days are ridiculously far out of compliance with US/EU regs and basic common sense for contamination.
If you're hell-bent on using a crappy knock-off belt to save a few bucks, you could put it under vacuum to try to suck out the residual chemical gas faster. Just apply the vacuum very slowly / in stages (say over 10 minutes) so you don't get decompression blisters in the rubber. You shouldn't need a hard vacuum, dropping to 0.5-1 psia or 0.05 bar absolute for a day or two should help significantly. No guarantees though.


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Analytic equations to make algorithm of 3D printer
I have a project in the 3D printing. the aim of the project is to realize the control of the 3D printing.
the type of the printer is a printer with cables.
the problem seems to have some development both in mechanical and robotics engineering.
first of all, as our tutor said, we should find the dynamical and the geometrical equations and from those equations, we can find the algorithm to control the system of the 3 D printing.
Well, my question is particularly about the dynamical equations in 2D as you can see in the picture above.
the idea  is to find equations of :
- L1 and L2 in terms of xa and ya : which I already found as you can see in the picture
- xa and ya and teta in terms of L1 and L2: which I cannot find ! I would lilke you to help in this point.
thank you in advance

And here, I add the dynamic equations and I would like you to check if it is ok

Also, I would like to ask you some questions about the dynamical equations. as I am new in this forum, should I post my question in another post?. (the reason why I didn't ask you in the comment, because I want to share a picture where there is the mathematical calculations, as I cannot share a picture in the comment)

Zaatifi: Thank you for adding a picture to your question. If the dynamic equations you mention are not directly related to this question, I suggest you ask about those in a new question. Also, if the question is not directly relatable to 3D-printing, you might want to ask it in either the Mathematics or Robotics sites instead. You can find links to other Stack Exchange sites from the menu in the upper left corner of this page.

In addition, the title of a question is the first thing any other users will see. Would you consider making the title more specific? Perhaps add what kind of printer and what kind of equations the question is about. That will make it easier to differentiate from other questions in the future.

thank you very much for your guidance. I still have 2 questions to be familiar with this nice forum. 1. how can I modify the title of this post ? 2. my new question about dynamical equation concerns this post and concerns the 3D printing for making houses, and I want to share this question in a picture in comment, but I notice I cannot add a picture in comment, how should I do? thanks for advance

A fairly common way to add additional information to your question in response to other users answers, is to edit your own question, and add a section at the bottom with a header perhaps saying "Update: ...", and so on. This way, you can add extra images, code snippets, and so on. To edit your question, press the edit-link below your post. Here you can also change the title, add tags, etc.. Hope that helps. :-)

Have you seen the B&TRap page and the videos it links to?

Can any one please mention the source(research paper or text book) to get these dynamic equations of a 3D printer.

As shown, the mechanics are under-constrained. You can't solve for theta because you have three degrees of freedom (X, Y, theta) and only two constraints (L1, L2). Gravity will tend to bias theta in a particular orientation, but the geometrical stiffness of this arrangement will be so low that it will not be possible to do 3D printing.
To calculate the free-hanging orientation of theta, you will need to know the center of gravity of the end-effector, and solve a system of equations to find the angles and tensions for each cable that produce force vectors which sum to equilibrium with the gravity force vector through the COG. Unfortunately, the tensions will be a function of the angles, so it's not trivial to solve. As a hint, the virtual intersection of the two cables will be coincident with or directly above the COG in all equilibrium positions, and the horizontal components of the tensions in the two cables will be equal.

M. Ryan thank you for your question. Exactly, you view is right. In fact, it's impossible to solve this equation as my tutor said.

As you can see I added the dynamic equations in the picture 2, can you check if is it all right ?