3D printer for robot parts?

[Cromulent]

I want to make a simple robot and was thinking about 3D printing the parts for it. The problem is I'm a complete newbie when it comes to 3D printers.

Can anyone suggest a decent 3D printer that will last a couple of years at least? My budget is flexible. I also use a Mac so I'd like it to work with that.

[SanctePieDecime]

I have an Ender 3 printer made by Creality that has lasted me several years. You can download the slicer for Mac. I personally do not use the Creality slicer, I use the Cura slicer by Ultimaker that works with my 3D printer; that also has a Mac download option.

It is high quality, but there is a lot of learning and tuning to do to optimize the quality such as the speed the axes move at, how far the filament extrudes, optimum bed and nozzle temperatures for different filaments, and so on.

I was printing new knobs to replace ones that were missing on an old analog oscilloscope I purchased about a year ago and that involved printing some very tiny teeth to grip onto a potentiometer head. It took some tuning of the printing settings, but I was able to get them to print really well. The knobs slide on snugly without having to be forced and the teeth engage the potentiometer knob enough that I have no concern of it ever slipping.

However, for this same oscilloscope, I had to print a new power button extender to reach the power switch all the way in the back and I had to print it as two parts because the 3D printer wasn't big enough. So, make sure you check out the dimensions on whatever 3D printer you end up buying to make sure it is big enough to print what you need to print. Alternatively, you can decide if you are willing to just print parts in pieces and then connect them together.

I am sure that there are plenty of others on this forum who have high-quality 3D printers to recommend, so by no means be satisfied with just my answer, especially since this is the only 3D printer I have owned.

[Cromulent]

Thank you very much for the reply. That is useful information to know. The more I read about 3D printers the more interesting it becomes.

I'll do some more research.

[Fred27]

3D printers are great, but you should expect to do a fair bit of fiddling and tweaking to get a good print. The process of getting a good print seems as much a hobby as churning out parts!

I went with an Ender 3 V2 a while ago and was reasonably happy with it. However, I like printing with ABS and it didn't manage the higher temperatures very well. Creality stuff seems pretty good so I then got a Ender 3 S1 (and the laser diode add-on).

[kripton2035]

take a look at the bambulab A1 or A1 mini. if you have the budget, the P1 or X1 are better .
there are plenty of videos online to compare them, and with the older and slower ender.

[richnormand]

I have an old MK3s from Prusa that is used almost every day for the past four years or so.
That is a reliable, rugged, pretty fuss free unit with many features like auto leveling, heat safety, quiet operation, flex steel build plate, Prusa slicer, Prusa support and such.
They are available used at very decent prices now that people are upgrading to the MK4 and the BambuLab units.

A friend got an Ender at about the same time and after the sorting and all the upgrades ended up at a similar price range as the MK3s in the end.
Go to the Prusa website and get a download of their introduction to 3D printing ebook.

EDIT:
forgot to mention much of it is open source (software and hardware and controller schematics)
I also use a FlashAir SD card that connects to my network and shows up as an extra disk on my computer. Very convenient.

[BennoG]

I went for a prusa also for my first printer.
It works problem free for the last 4 years not a lot of fiddling needed.
I usually put the sd card in turn it on and walk away, come back a couple of hours later and print is done.
All the el cheapo printers you have to tweak the first layer, and babysit the printer until at least the first layer is done.

P.S. I am even looking to replace my MK3 for the new MK4 that is almost double the speed of the MK3.

Benno

[Cromulent]

Thank you all. I have a bit of research to do!

[BILLPOD]

Good Morning Cromulent, Have a look at The 3D Printing thread;  that has over 3,000 responses.

[Coordonnée_chromatique]

The Ender 3 is a very unprecise printer, the Ender 5 is a better choice for the dimentionnal accuracy.
Here is a dismantled Ender 3, as you can see, the profile cuttings are not perpendicular.

[aeberbach]

The difference between a $200 printer and a $1000 printer is usually not the final print but how much of your time it will waste per print to get a result. The $200 printer is only cheap if your time is worth nothing and you don't mind spending another $200 in parts!

Currently have a Prusa MK4 assembled from kit - not one failed print or even minor annoyance in a year.

[Coordonnée_chromatique]

The difference between a $200 printer and a $1000 printer is usually not the final print but how much of your time it will waste per print to get a result. The $200 printer is only cheap if your time is worth nothing and you don't mind spending another $200 in parts!

Currently have a Prusa MK4 assembled from kit - not one failed print or even minor annoyance in a year.

And what about the dimentionnal accuracy, wich IS the absolute first criteria of choice of every part machining or printing ?

[SanctePieDecime]

Well, my printer has great dimensional accuracy. As I mentioned in my response, I had to 3D print some parts with tiny details. I have included some pictures. The coloring is because of the style of filament I was using (a kind of textured look).

I can't say that I would be able to make a judgement about the setup time and effort for $1000 3D printers, but I can say that if you spend the time and effort to calibrate 3D printers of the quality of the Ender 3 (which is not a $1000 printer), then you will still be able to get enough dimensional accuracy for just about any project you need.

[aeberbach]

And what about the dimentionnal accuracy, wich IS the absolute first criteria of choice of every part machining or printing ?

For some. Some never really require much accuracy. https://www.printables.com/model/858887-sign

[MarkF]

I have been running a Creality CR-10 Mini for the past six years with good results.
As mentioned above, it takes a little effort to get calibrated.  But, well worth the effort.

One important thing not mentioned yet is the choice of Marlin or Klipper printer firmware.
I was considering a ELEGOO Neptune printer  when I first became aware of the Klipper systems.
The hardware is significantly different to necessitate its choice before selecting a printer.

As far as slicers go, I used Cura for a long time was always frustrated with the GUI controls. 
I switched to the PrusaSlicer a year ago.  It works with many printers beside Prusa brands.
The PrusaSlicer has practically all the same capabilities as Cura and continues to support my Windows 7 machine.
(Which came first, the chicken or the egg comes to mind when comparing the two.)
The slicers is regularly being updated and upgraded with new features.
You can try both without the need for an actual printer.

The PrusaSlicer and FreeCAD are my current goto's for 3D prints.

[Coordonnée_chromatique]

Well, my printer has great dimensional accuracy. As I mentioned in my response, I had to 3D print some parts with tiny details. I have included some pictures. The coloring is because of the style of filament I was using (a kind of textured look).

I can't say that I would be able to make a judgement about the setup time and effort for $1000 3D printers, but I can say that if you spend the time and effort to calibrate 3D printers of the quality of the Ender 3 (which is not a $1000 printer), then you will still be able to get enough dimensional accuracy for just about any project you need.

All filament printers are very low dimentional accuracy devices, i was unable to have a good axiality on large revolution parts on the Ender 3. A 100 millimeter 2mm thikness tube was around +-2mm on the circularity and around the same on the conicity on a campaing of ten parts of averaged measurements.

I havent used my micrometric calipers for this campaing 

[wraper]

All filament printers are very low dimentional accuracy devices, i was unable to have a good axiality on large revolution parts on the Ender 3. A 100 millimeter 2mm thikness tube was around +-2mm on the circularity and around the same on the conicity on a campaing of ten parts of averaged measurements.

I havent used my micrometric calipers for this campaing 

Says all filament printers, then uses substandard garbage that is barely useable without upgrades as an example.

[Coordonnée_chromatique]

All filament printers are very low dimentional accuracy devices, i was unable to have a good axiality on large revolution parts on the Ender 3. A 100 millimeter 2mm thikness tube was around +-2mm on the circularity and around the same on the conicity on a campaing of ten parts of averaged measurements.

I havent used my micrometric calipers for this campaing 

Says all filament printers, then uses substandard garbage that is barely useable without upgrades as an example.

The Ender 5 is around ten times better in term of accuracy, it is a great printer for the price and don't require any modification.

[CatalinaWOW]

Saying any device is dimensionally accurate or not is meaningless without standards.  No 3D printer is going to be able to hold 0.1 mm accuracy.  Best accuracy for such printers will be on the order of nozzle size, which is most commonly 0.4 mm.  With care you can do better for critical dimensions, but unless all dimensions of your part are integral multiples of the line width tweaking in one area will cause a loss in another.

The 2 mm number mentioned above for an Ender 3 is indicative of a serious issue, either in printer setup or measurement (which is challenging in large thin wall parts with somewhat flexible materials).  Mine routinely does far better than that.  I would look at belt tension and support roller adjustment before condemning that breed of machine.

Another comment.  While FDM printers will always have challenges achieving much better than half millimeter accuracy, repeatability in my experience is far better.  I haven't quantified it, but would estimate something under 0.1 mm for my Ender, and less than that for my Bambu labs machine.   That means that once things like box lids and joints are adjusted (commanded size changed to get desired real size or fit) all future parts will fit. 

[wraper]

Saying any device is dimensionally accurate or not is meaningless without standards.  No 3D printer is going to be able to hold 0.1 mm accuracy.  Best accuracy for such printers will be on the order of nozzle size, which is most commonly 0.4 mm.  With care you can do better for critical dimensions, but unless all dimensions of your part are integral multiples of the line width tweaking in one area will cause a loss in another.

Nozzle size is about how fine features in can print, not accuracy.

[Old Printer]

This probably should be moved to the 3D printing section, but anyway..  I am new to 3D printing as well, but got involved because of a project I am working on with some friends. We build micro model airplanes and are working on servos that weigh less than a gram, 500mg is the goal and we have some working, but not refined. Anyway, when accuracy and detail come up in this thread no one has mentioned resin printers. They are a real PITA with the nasty resin and all the cleanup, but for making small, precise parts with fine detail they are the way to go. The newish Elegoo Mars 4 has amazing resolution and I have used one to print the gears in the attached pix. The larger gear has a diameter of roughly 3/8" or 10mm. The holes for the carbon fiber shafts are .025" / .5mm and require just a stroke with a reamer to final size.

[wraper]

^I have an SLA printer, however I barely use it. Not really useful for functional parts, even with expensive high toughness rigid resins parts still will be brittle compared to FDM, not to say compared to tough filament like Nylon. So with SLA you can either get soft stretchable parts or rigid brittle ones. Also forget about functional parts with inexpensive regular resins (unless it's a very light load with no mechanical impacts).

[Old Printer]

You are correct about the toughness being a problem. These gears carry a very light load and do not run constantly, as a propeller/motor gearbox would. Siraya Tech Mecha is the resin of choice, with 15% Tenacious added in for toughness, as it has good surface wear characteristics, but it is still brittle. It is also not an easy resin to print with and requires a lot of fine tuning. Resin printers are mostly popular for making action figures with amazing detail that just sit on a shelf.

[Coordonnée_chromatique]

Saying any device is dimensionally accurate or not is meaningless without standards.  No 3D printer is going to be able to hold 0.1 mm accuracy.  Best accuracy for such printers will be on the order of nozzle size, which is most commonly 0.4 mm.

It is a little more complex because you can print a precise part if you overlap the deposits of a solid infill larger than 0.4mm, i've printed linear bearings with some Ilgidur150 with very tight tolerances but it had been an headache (never again !)

[Doctorandus_P]

I had a look at the creality website because it's mentioned a lot in this thread. After getting the second popup (2nd for the store website) for coupons or whatever within a few minutes I just gave up and closed the site. I find such thing very consumer unfriendly and annoying.

I am guessing that with consumer level plastic poopers you can get an accuracy of a few tenths of a mm. One of the properties of such printers is that the dimensions of the final product are not the same as the vectors you send to the machine, because it squeezes out the plastic though the nozzle and then it gets squashed and spread out between the nozzle and the previous layer. As a result the final dimensions are very much dependent on the printing profiles used, and probably also on the particular plastic. Filament quality is also an important factor. For example small differences in the thickness of the filament will result in changes in dimensions in your product because it varies the amount of extruded plastic, and thus the amount the plastic gets squeezed to the sides.

What sort of robot arm do you want to make? Do you mainly want to make a cheap toy that sort of works, or do you want to get some accuracy out of it? From what I have seen, the robotic arms with hobby servo's are the cheapest and simplest to build, while with stepper motors you can get more power and accuracy.