Comments sought on new build: A CNC Router for RC Gliders and Planes

[njhussey]

Cheers Jazz, the tray will be a removable metal one (I’ll get the local tin bashers to knock one up from 2mm steel and run a weld up each corner to seal it and it’ll be loose in between the frame so I can lift/slide it out. I’ve still got to detail things like all the stepper mounts, end stops, limit switches etc. but didn’t want to go into too much detail before getting the basics done! I’ve quickly added a couple of stops at the bottom of the rails and added/changed the stepper mounting brackets for the X and Y axis.





I’ve half a mind to make the leaning frame in one piece and the router bed in one piece and bolt them together. This way I’ll be able to separate them in the event of a move (very likely in the not too distant future) so I won’t need a Hiab to lift it over the back wall to get it out of the garden!!


I now have a few questions to ask before I get going on ordering bits and pieces for the build so again would appreciate the benefit of everyone’s combined knowledge!

I’m going with SBR20 rails for all 3 axis with SBR20UU carriages. X is 1300mm long and Y is 750mm long, Z is 400mm.


Ball screws. I was thinking of 1605 (from Chai) driving them with belts at 2:1 ratio on the X & Y axis and 1204 for the Z being direct drive from the 3Nm stepper. Is the 1204 ball screw OK for the Z or is it better using the 1605? I’d be happier using the 1204 to use the smaller ball nut and therefore getting an extra little bit of length on the X axis.


For the Stepper motors I was thinking of 4 of the 60BYG301B 3.1Nm motors from CNC4YOU? Any others to consider, the SY60STH86-3008B from Zapp? Any difference (I can’t see any in the specs particularly) in the two apart from price?


I’m thinking of going with either the CW-885 Drivers from CNC4YOU or the AM882 Leadshine from Zapp. I’m leaning towards the AM882 but what are your thoughts? I take it that I can drive the 2 X axis steppers from the same driver so will only need 3 drivers? Is the performance of these drivers much better than the 50V drivers? I think I’d rather spend a bit more and have better “future proofing” even though for cutting balsa and thin ply the 50V drivers will be fine I’m sure I’ll be cutting Ali and all sorts after a while!


Which BOB would you recommend?


Power supply. Is it best to buy one readymade, i.e. the PS806-5 from Zapp, or have a go at making my own? Is there a significant saving to be made?


I was going to do this all on a shoe string budget (see first post on this thread!!) but now don’t have to so would rather buy decent equipment (without going completely over the top!)