Quote Originally Posted by CheekieMonkies
Wow your machine looks really nice ! "iffy" ?

Nice job on the motor mounts, i plan to do somthing like these for my machine. I was thinking about using Delrin to make them for my first machine, however ali would be much nicer !

Regards,
CM
Hi - by iffy I mean a bit rough round the edges and unfinished... It was just a rough job, although by using a couple of simple jigs to ensure holes were square and parallel it did mean I didn't need the end plates and the whole thing is accurate to around a thou (obviously ignoring sag, load deflections etc). MDF may be 'industrial cardboard' but it's amazing how accurately you can machine it.

I should think the Delrin would be fine - I used ali because that's what I had. This is my 3rd attempt at building a CNC machine - the first two reached various degrees of completion before dissatisfaction caused me to take them apart again.
I think it's possible to get too precious:- "is this the right material?", "will this be stiff enough?" etc etc. Hence my 'just do it' comment.
If I'd designed the Rockcliffe machine myself I think I'd have given up on it long before completing it for all the same reasons, however the simplicity of the design and the fact that people are already out there using them meant I could just ignore my misgivings and try it.
It's not the stiffest machine in the world, but just like the real world you simply compensate by taking smaller cuts. After all you wouldn't expect an X3 to cut like a Bridgeport...

Now it's built and in use I reckon in the past I've been way too precious, I'd happily build machines now using drawer slides, skate bearings etc. Reading various forums most people are simply too finicky and they're not helped by the 'money's no object' groups who rubbish any design not using 'brand x' linear bearings and 2" thick ali plate at some astronomical cost.

Good luck with your build anyway! You're only a few miles up/down the motorway so if you need any help...