Community thoughts on 3d printed extrusion brackets vs aluminum?

Basically the title. I’ve got the extrusion for my repeat build, and I’m thinking about milling a bunch of L and T brackets for the corners out of some aluminum sheet laying around (maybe 3mm give or take).

But it occured to me that they might sorta be in the way of adding panels to the outside. 3d printed brackets cm could go on the inside corners, and I’m confident that someone has already built and shared all the brackets I could ever think of (and twice as many that never crossed my mind).

All I can really print on my current printer with any reliability is pla, but I think even when it’s enclosed it’ll be cooler than steppers, so maybe it’s adequate. I also have a resin printer, which is probably more accurate, but the parts are definitely more likely to break if i stress them before getting the sides on.

Thoughts?

There are some definite advantages to 3D printed fixtures, additional features for wire management, for example, even if it’s just a slit for a zip tie.

The 3018 CNC that I have uses some 3D printed braces for the gantry. PLA will have a stiffness advantage.

I would probably give the braces a bit more meat to them than the aluminum ones, so long as I had very high confidence in how square my printer is, but ultimately, if you add side panels, those will determine the strength and squareness of the overall structure. In that case, I’d say that the 3D printed braces only need to assure thst the frame is strong enough for initial assembly.

You can also make some specialty braces, for example a set to bolt in the front uprights and Z axis extrusions that enforces the spacing (50mm, IIRC) and keeps them parallel. You could also build in a bypass for the Z extrusions for the CoreXY motors to keep the wiring out of the way. This would require a corresponding opening in the side panels, but that’s easy enough.

I considered this possibility, as well, but decided on the aluminum braces. I kind of regret the decision, truth be told, and I’d do it differently if I were to build another.

As for the temperature… if the inside gets hot enough to deform PLA braces, would it not deform the CoreXY parts in the back corners? The braces holding the X gantry rail? Motor mounts? Seems.like you’d have a lot more problems than an out of square frame…

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Man I’d say if you have PLA parts already why not but I’d be real worried about using PLA anything in an enclosed printer. Between motor, hotend, and bed heat it can get pretty spicy in there. Maybe your first order of business after it’s set up would be printing ABS replacement parts? Dunno. Would hate to see you build a great printer only to have it deform to crap after a long print.

The enclosed printers I have normally run 50°C and can reach over 70°C on longer prints. That’s all passive heat. Those temps would be catastrophic to PLA parts.

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That’s a nice idea!

Yikes, that’s a lot higher than i would have guessed.

Thanks guys, I’ll give it some more thought. Those are some really good points from both directions.

I used Ryans corner bracket design for mine printed in PLA. I have no plans to enclose my printer though so that may make a difference. I just liked the look of his brackets so much better than the metal ones i got from amazon.

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wow, my printer doesn’t get much hotter than 90°F when printing hips with a 100°C bed.

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Your chamber temp is probably what @turbomacncheese should expect to see. For a bunch of reasons my printers run hotter than most. But even at 90°F I’d be really hesitant to recommend using regular PLA. Is there a PLA designed to operate at these temps? Has to be.

The HTPLA is not very standard. The instructions say that if you want them to work at higher temps, you need to aneal them at 210F or whatever, which can cause warping. I’ve seen some people boil them, others put them in their kitchen oven. I haven’t tried.

Hey @SupraGuy, what would you do differently? Personally like your ply enclosed/reinforced Alu extrusion setup. Seems sturdy enough that corner braces aren’t needed even? Could mill some inside ply panels I guess?

Been curious to see what reliable print speeds you Repeat v2 builders are able to get? Thoughts on Ikea Lack frame with ply/MDF/acrylic panels to enclose and shear strength? Panels are the braces. Trying to figure out ideal cheap stable material, have some porcelain tile left overs, but making precise holes is PITA.

Curious if anyone’s used T slot/track channel bits to mill soft/hard lumber and/or ply/something into serving similar purpose that extruded Alu would serve? Laminate/lumber flooring?

Edit: Alu extrusion is ~$2.5 linear foot, cheaper than square tube, cheap enough that probably doesn’t make sense to bother experimenting with cheaper material requiring more involved labor. EMT is $1 per foot but more work to attach fittings/panels.

Dang. Really ASA would be ideal. Would need to make a temporary enclosure and have an all metal HE for the open air printer. Not nearly as difficult as ABS though.

So as it sits, I have some pockets milled into the plywood sides to have wires pass. I think I’d use 3D printed parts instead, so that they could be removed and have the wires accessible and removable without having to take the whole side panel off. Aside from that, I probably WOULD want to use printed braces, particularly braces with some provisions for cable management. I have some slots cut in the wood for zip ties, and it would be nicer if I could keep everything inside the frame.

My first repeat, I typically print PETg. I print with a 250°C hotend, and a 100°C heated bed. Even in the summer when it’s often uncomfortably hot in the house, I don’t see 50° in the printer chamber. I have had no problems with printed parts softening in that printer.

Time will tell with this one. I hope to be printing ASA and have dreams of printing PC and nylon parts, both of which require even hotter temperatures. I strongly suspect that my first ASA print will be a replacement for the cooling fan duct, probably same with nylon…

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Yea there is, but like Jeff said, it’s not common. The few printed parts in my printer that are left are petg though.

Looks like the only thing you’re missing is 10° and some filament! :smile:

Maybe I’m just the odd one but I print ASA on my Cr10s pro open air at 250° hotend and. 80° bed no problem at all. Zero fumes. Oh and I do slow it down and turn off part cooling. My z mounts, x carriage and part cooling blower were all printed in ASA

Nice! My Voron was printed in ASA on an Ender 3 I put in a cardboard box. It’s pretty forgiving stuff.

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Yeah i havent had any issues with it. Now i have never printed with ABS or Nylon so i have nothing to compare it to. But for me other than the higher temp and turning off part cooling it prints just like PLA

Your right it prints about the same just hotter. ABS absolutely needs some kind enclosure or it curls but otherwise prints exactly like ASA. I struggle with Nylon. It sucks up SO MUCH moisture and becomes unprintable way too fast. I’ve spent more time drying it than printing it.

I have that problem with just about anything here. Well not that bad but still. Being in Florida at just about 90% or better humidity year round and in an old very leaky house it doesn’t take much to get wet filament. I been researching drying and dry boxes lately. Bought a cheap dehydrator off amazon and some rubber made food safe sealed containers to build me a few dry boxes. Hoping I can run it though the dehydrator and then strait into the dry box and print from there.

Oh wow. Yeah it would be a challenge down your way. PC is sucks up moisture too. But no where near as bad as Nylon.

Sometimes I miss Florida, sometimes I don’t. Running the AC in January and February just because I want slightly less humidity in the house is one of the things I don’t miss.

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