Transferred from my Hi from Hereford thread:

Hi folks, I've been doing a few things: looking at commercial desktop machines and how they go together, looking at build threads and how they evolve, looking at some of the rebuild of the Chinese stuff and doing some parts costing. Initially looked at linear bearings and tracks for the Y & Z axii, motors, lead screws etc., even though I'm looking at a quite small machine the cost is rising sharply. Sharply enough for me to look as supported rails rather than linear bearings/tracks. Not looked at the electronics yet. All part of the learning process, I need to take more time. I was hoping to get this project going quite quickly but I think it will be a few months before I pull all the bits together ready for assembly.

I'll put some of my drawings up for discussion over the next few days to see if my thinking is in the right direction. Still looking at a fixed gantry with moving bed. Twin support rails under the bed (Y) and across the X axis and paired rails on the Z axis...

Not decided yet on the type (diameter or pitch) of lead screw for each axis but decided not to use toothed belt drives.

Cheers
Francis