Hi Chaps,

There are (at least) two problems with selling my current machine. a. Overcoming the shame in admitting I bought it and b. I wouldn't wish it on anyone else ! The wee beastie is really only a collection of bits of ali profile and some trapezoidal screws. When I mean rebuild, I only intend to use the steppers, spindle mount and T slot plate. Some of the remainder of the machine might furnish profile and motor mounts, but the rest would go into my non-ferrous collection.


Chai has quoted me on supported rails and bearings, leadscrews, ballnuts and end bearings. I have requested they are only machined on the driven end, so I can turn them to the final fit. For the small cost of the rails and leadscrews, I have been generous in length allowance. The machine can only be 600 x 500 x 200 MAX. I have a MIG and 4 saws capable of slicing steel, as well as 4 angle grinders (there is a short but very boring story as to why 4 of each !).

On a small machine, the usual practice seems to be to drive the long axis with one leadscrew centrally under the machine. How problematic would it be to put it to one side ? Could any skewing be sorted with a parallel motion mechanism of wires and pulleys like draughtsmens' tables ?

My main thought at this early stage is 'why put a leadscrew where it gets shit thrown at it ?' Are there any major mechanical disadvantages to starting the design as a gantry with the long axis screw at the top ? I think that I probably ought to get some drawings done to clarify my thoughts.

Cheers,

Rob