Toothed belt size selection help.

Hi,

I am busy in the design stage of my CNC hot wire foam cutter project. I have decided to use toothed belts to drive the axises. I am intending to use a closed belt with a turn around at one end, i.e. not an "Omega" drive. Originally I was going to use T5 x 10mm wide belt, but I am now thinking of using T2.5 x 6mm belt because it will allow for a littler neater design and also higher resolution for any given size. The two Z axises will have a travel of about 500mm, and the to Y axises about 1200mm.

Any thoughts, is T2.5 x 6mm OK for light load this job ?

Also do you get problems with the two sides of the belt slapping together over large distances like I have ?

And finally how do you figure the resolution you are after. Do you make it 10 times greater than the accuracy you wish the machine to have ? I.E. I wish to cut to 0.1mm resolution so make every step on your steppers = 0.01mm ? Or do you simply make each step = 0.1mm ? I need a rule of thumb !

Cam.