Been designing and prototyping a 3d printer frame that will be made from 1/2 inch electrical conduit! Converting an anet a8 to a corexy and trying to keep the budget tight. Finally (after half a dozen test prints) found out the tolerances of my printer and made these bracket designs to be a pressure fit to the conduit. Ended up going with the design farthest to the right that will allow me to drill a 3mm hole into the conduit for added strength to the frame. Let me know your thoughts on the idea!
Damn that’s clever. I’ve been designing a printer that uses 1" aluminium square tube for the purpose of being a printer with materials easily sourced in Midwest America (getting the typical 20mm T slot is too expensive to buy and ship). Never thought to use conduit, despite working in an electrical department.
@_Spice I feel like you will get a much more rigid frame from the aluminum, but the conduit is so cheap that even if it doesn’t work out, didn’t spend that much on it 
In case you want to see another take on the idea:
http://reprap.org/wiki/Uconduit
I thought about building one a few years ago but decided I cared too much about precision…
Have you thought of stiffening by adding 45° holes for cross-bracing conduit pieces to your corner fittings?
@mcdanlj Yeah I’ve been thinking about it and thought it was a good idea, but was close to the end of a roll of filament 
. Figured it would be good enough for now. Also there will be conduit supports halfway up the z axis that should make up for it.
Bear in mind the the tolerance on OD is not held very tightly in EMT. Cool idea though. I have been considering something similar for a different project.
You could also screw pieces of Masonite or 5mm plywood to the fittings later if you find you need more rigidity. Neither is horribly expensive. What constraint system are you thinking of for your XY?
@Mark_Kennedy … Yes, and that’s why Uconduit uses compression fittings.
@Mark_Kennedy Yeah that’s another reason why I printed so many different spacing rings (a couple are in the first two pictures to the far left). Ended up that 18.2mm was a good compromise as they all pressure fit nicely, some are slightly tighter but none are too loose.
@mcdanlj I’ve made a rough design that needs redoing for the motor mounts (made for the previous clamp design). At the opposite ends there will be idler bearings with the same basic design to fit over an m3 screw. But basically using the same corner brackets and adding to it for the motors and idler bearings. https://lh3.googleusercontent.com/sqEegqT390xcNhbbQnxoefzrl2nQQ821uKB5so2czi1N9FdpB0O1_xPcy2pIykOMwpt8hfbf
Do you guys happen to know how well pla makes screw clamps? Thinking I could make a circle (bracket) to slide over the conduit with a slot cut out on one side and some portions sticking out with screw holes to squeeze around the pipes and make 45 degree supports for the sides and bottom that way…
@jacob_haney they’re about as ridgid as any other plastic, except polycarbonate. Decent rigidity, but if it’s in a high heat/friction environment, or gets too much torque, it will fail.
I am happy someone is doing this
If you use square tubes, you can do without linking parts from plastic, much more rigid. Look for Quadrap, I built one some years ago, it’s very stable. Only difficult part was alignement.
@Daniel_F I would have gone with aluminum square stock if not for the price difference. 20 dollars for 8ft. Compared to 1 and change for 5ft of conduit. Starts to add up quickly
Came up with a simple 45 degree support. Think this will do the trick?https://profiles.google.com/photos/111464289162600838321/albums/6518781836537832977/6518781834075200178
@jacob_haney I got mine at a steal at $12.49 for a 6ft section. A day after the price Rose to $17.99.
cool
zelf replicating 3d printers would be awsome 