Ive been building my CNCsince about 07, I think, starting with basics and progressing in a downward direction ever since, its only for PCBs so my needs are minimal, size wise that is and the product so far has been great, until the Easy board I built blew the pc, sooooo I thought it was time for an upgrade, bought some boards from Routout and ordered new X &Y 10 x 2mm Acme thread from Merchant Dice, made a tap from the end of the rod, drilled out the plastic nut from 6mm that was worn to 19/64 and cut a new thread for the X axis nut, no slop, no backlash and was smooth, was well chuffed. Y axis might prove to be a problem because it will need a link from stepper to 10mm acme so will need something with a bit of bendy in it, and possibly a new short thread tap and ram it onwith a bit of sticky stuff.

But I have a problem; X axis is through a cam belt drive from an old scanner with plastic gears, (I assume there called gears) it only has 20 teeth with a 1mm pitch as far as I can tell, and is rather small to cope with my larger 10mm thread, I would like to increase its size a little to allow a/ a keyway in the shaft b/ less strain on the belt. It would be a simple matter to copy the original in ally but to increase its diameter and get the right number of teeth with the right spacing just blows my mind, Does anybody know if theres a program or formula for working out such things? I have been looking for some time now but must be asking the wrong question.:whistling: