Feasibility of custom 3d printed case brackets

[Colinreay]

Hey everyone, you may have read my last thread on Actobotics, on the topic of if it was good for making a case. Well, after thinking about it more, I changed my mind, and well, probably will again in the future (maybe to a full 3d printed case frame like LZ7)

After more dilberation, I came up with this bracket design yesterday


The bracket has inset M3 nuts, so that aluminum angle extrusions can fit flush on the outside, with thicker 6.35mm (1/4 inch) acrylic panels being used inside (which I want to laser cut into a cool vent pattern, maybe like the Deepcool Whetstone build.

My question is: Do you think it is strong enough, and do you think it can be printed with an FDM printer like the Ultimaker 2? I'd love to get it resin printed, but on the budget of a 15 year old, I don't exactly have a lot of money to put into this. If I can't 3d print them on my uncle or High Schools, I guess I could resort to getting them printed by someone with a form/sla printer on 3d Hubs!

I'm still debating on whether to use aluminum channel though, it seems like I could achieve something sleeker and more flexible with 3d printing.

 

[Kmpkt]

Having done 3d printed items before, I can tell you that even at the highest qualities most 3D printing isn't as accurate as other methods of production. I think that with what you are planning here, you're likely going to end up with a lot of parts that don't quite fit.

 

[iFreilicht]

I would say that it can work, especially with the layout that you came up with structural integrity shouldn't be too much of an issue, but you'll have to make sure to give generous tolerances. At least 0.5mm offset from the outline of the hexnut, maybe even more.


What you should also think about is how you're going to fix the nuts to the brackets. Normally I would advise against gluing them, which seems to be what you planned on doing. Instead you should have a wall with a through-hole in front of the nut, like this: (= is the panel, - is the bracket)

BOLTBOLTBOLT
=====BOLT=====
---------BOLT--------
--NUTBOLTNUT--

This way, the nut can slide around a little, giving you higher tolerance for misalignment, and printing is not accurate at all so you'll need it.
You may still want to try and reinforce the piece where ever it could help, and think about which orientation it's going to be printed in. Holes that have a axis perpendicular to the bed are more accurate than the ones with a parallel axis, so the latter once might need a little higher tolerance and - in the case of hexagonal holes - should be oriented with one corner to the top instead of an edge, especially when we're talking about sausage printers like the ultimaker.

 

[Colinreay]

I would say that it can work, especially with the layout that you came up with structural integrity shouldn't be too much of an issue, but you'll have to make sure to give generous tolerances. At least 0.5mm offset from the outline of the hexnut, maybe even more.


What you should also think about is how you're going to fix the nuts to the brackets. Normally I would advise against gluing them, which seems to be what you planned on doing. Instead you should have a wall with a through-hole in front of the nut, like this: (= is the panel, - is the bracket)

BOLTBOLTBOLT
=====BOLT=====
---------BOLT--------
--NUTBOLTNUT--

This way, the nut can slide around a little, giving you higher tolerance for misalignment, and printing is not accurate at all so you'll need it.
You may still want to try and reinforce the piece where ever it could help, and think about which orientation it's going to be printed in. Holes that have a axis perpendicular to the bed are more accurate than the ones with a parallel axis, so the latter once might need a little higher tolerance and - in the case of hexagonal holes - should be oriented with one corner to the top instead of an edge, especially when we're talking about sausage printers like the ultimaker.

'

Incredibly helpful . Thank you so much!