Resin Printer or 3D Printer For Frc?

We are going to buy a new device as both of our Creality CR-6 SE printers broke down. But we can’t decide if we should choose a resin printer or a normal 3D printer. We will mostly use it for parts on robot like bearing holders or spacers. Most important thing for us is durability.

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3d printer. Resin is weak.

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FDM is what you need for 95% of your parts. Anything structural absolutely!

Look for something with at least an 8 inch cubed or bigger bed. Most of our prints could be 40% infill and survive with proper fillets. We printed a ton of parts FDM this season and the biggest mistake is leaving too little plastic or straight lines at joints between faces. It will seperate there first every time guaranteed.

When we needed a resin printer it’s for little fine detail parts, hex spacers or anything that will not be taking lots of force. Even over tightening bolts on a “custom pi case” we made, caused it to crack right away. The upside of a resin printer for spacers was getting them all in one batch vs printing each individually on an FDM (mass production resin wins out)

If you use a .4 nozzle or smaller you can get most of the detail you’d want for FRC parts with an FDM only. If it’s a bigger part you can go to a .8 and get a 4x increase in speed but lose some finer details. Either way FDM is my recommendation!

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Definitely go for FDM. We use a mix of PLA and PETG on our robots with the ability to use carbon nylon (I dont know if any nylon made it on the bot). Resin is great for detail but most resins are pretty weak. That said, I did just buy a resin printer and if I find it to be useful for FRC I may post about that.

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Resin parts can be strong, but for such a high-impact application, nylon or polycarbonate FFF/FDM is probably going to be the best. Not to mention resin is messy and toxic to work with. (nylon and poly produce VOC too, but are easier to manage). CF-infused filaments substantially increase performance in some instances, but some base plastics can make parts more brittle. Hardness ≠ strength.

Both have a place in FRC though, we plan on printing a NavX case out of resin. mainly just to experiment with it, but also because the resolution makes holes and ports easier

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I’ve only seen resin parts used in artistic and high detail model creation. I’ve not seen a resin that’s really usable for engineering applications but I’m sure they might exist, but would probably cost a fair bit more than FDM.

If you need a new printer I would consider a Prusa MK 3 or the new MK 4 and I’ve heard good things about the Bambu Labs X-1

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If you start getting into higher end consumer grade SLA stuff like formlabs you might be able to find a resin that will hold up in some applications. Formlabs’ tough 2000 is very strong and shock resistant from what I’ve experienced.

At that point, though, you’ll almost always get more value for money from something FDM. The resin I mentioned is $200 per liter.

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Assume resin printers are $$$$$, and material is $$$/unit. Go with an ABS-capable FDM/FFF printer, for $$$$ and material at $$/unit.

I’ve mentioned a couple of times before that 330 once was looking at 3D printed mecanum wheels, but what I haven’t mentioned is that before the SLS (nylon) wheels were made, a single wheel was made as proof of concept… SLA resin (don’t recall the type.) That single wheel didn’t last very long at all. The SLS wheels are still around in very random places.

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They make decent engineering resins, but for toughness:size and toughness:weight it’s hard to beat traditional FDM printers. I haven’t worked with a resin that’s as strong as FDM nylon.

There’s a lot of cheaper resin printers these days, but they’re slower than FDM in the same price band, and the resin is more expensive on average. Also, resin is super toxic and smells like death. I wash my hands three times after handling it.

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Resin printers can be fine for FRC, and they aren’t necessarily super weak (the Tough and Durable materials from FormLabs are plenty adequate for FRC), but FDM printers are going to be cheaper, easier to use, cleaner, often faster, and plenty effective for what we are doing. Resin printers are best for detail work that will probably never be necessary in FRC.

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The average consumer resin printer and resins just don’t cut it for structural FRC applications. We have printed electronics cases that are protected and spacers. They worked just fine.

Now. What was a great success was using a hollowed out resin part as a mold. Making molds for casting is hard. We tried FDM printed molds and while we did have some success we had too many less than perfect results. What we do is print a shell of the part with 2mm walls, using one of the tough clear resins. The shells have a hole and we pack it with dry chopped carbon fiber. We then pull a vacuum on the part and infuse epoxy. The strength and durability are fantastic. The student love to do it. Do we have to do it? No. But, the team gets first hand experience working with composites. We also do layups every year.

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In my previous comment I mentioned making Resin spacers. That’s valid and we do that, but then I remembered we also have a high temp TPU/ASA Hotend that we used for Hex Spacers this year. We could get a batch like what’s in the picture below (12 spacers of various lengths up to 1 inch) every 2.5 hours. On a Resin printer It’d be about 20 minutes plus wash & curing time. But hands down ASA is a great material to use if you have the capability. We also use PLA for Prototyping then ABS or ASA for final parts that need extra strength.

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I generally concur with the consensus that FDM printers are the way to go for 95%+ of what is required in 3D printing for FRC.

Don’t particularly agree with these characterizations, though.
Price will vary wildly by brand and printer size. There are cheap LCD 3D printer options just like there are cheap FDM printer options. And there are very expensive FDM options, just like there are expensive SLA printer options.

Ease of use will also, once again, vary by brand and what type of task you are doing. I’ve run “set it and forget it” prints on LCD resin printers plenty of times before.

Cleaner? I think context and specifics here are important. Both FDM and Resin printing have the potential for the printed product to need supports removed, but that will mostly depend on the specific print and how many overhangs it has. Some FDM printers may have soluble support materials to make this process easier, but that’s not a guaranteed feature. As for cleaning the machines themselves, a successful resin 3D print requires almost no cleaning. FDM will vary somewhat based on your build plate and bed adhesion. Failed prints on both technologies produce more of a mess, and cleaning resin cured to your fep can be annoying (although many printers now have options to help make that process easier by exposing the entire layer).

Faster is the one I disagree with the most. One of the biggest advantages of resin 3d printing is that print speed is almost entirely based on only 2 parameters, layer exposure time and Z-axis height. The length, width, and quantity of what you’re printing does not impact how long the prints take. So you can cram as many objects onto your build plate as reasonable and print them all at once, which makes resin printers particularly fast for printing many things at once.

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Thank you to everyone. We will go with a FDM printer. We are going to talk with our supplier to find the best fit for our environment and hopefully something that wont break in few months. If you have printer recommendations I would love to hear them (environment that printer will work is mostly below zero temps, and very humid).

You’re probably going to want to find a different space, or buy an enclosure or something. Humidity can make the filament swell and become impossible to fit through the nozzle. Source: I lost a roll or two of filament to humidity. There’s a reason most rolls come in vacuum-sealed plastic with a humidity absorber.

Unsure about the zero temps, but I suspect the heater might end up having issues? It might be fine though.

A filament dryer is an important addition to your printing set up.

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are you keeping it in a meat locker?

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Having printed a bunch with a Form 3 in the past year, I would run away from resin printing as fast as possible. The technology is cool and works great for high resolution or specific applications, but wow is it an absolute mess to deal with. You’re washing parts in IPA that gets super gross over time and it’s all just kind of not fun compared to an FDM printer with a spring steel bed plate where the parts just pop off ready to throw on the robot. Way less mess to deal with on an FDM printer in my experience at least.

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I mean, are they? One kind of part is, 100% of the time, going to be covered in sticky goop you have to wash off when you’re done printing. The other kind of part you could potentially take straight to your robot and put it right on if there aren’t any supports to file off. Saying FDM parts and the FDM process is cleaner, is no contest.

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Workshop is 5 metres underground💀

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