Hello cncpeople,

i have a an old Bungard CCD router. The axis drivers are build with L297 and L298 chips from vendor, and the serial interface are replaced with a new parallel interface(BoB from China and homemaid interface card). So far all works pretty good from Mach3.
When running longer jobs it seems that i loosing steps only in x axis, and y axis after zeroing starting about 0.2mm above working surface.

If i can get some help with steps per, it would really help me out for sorting out other minor problems.

The router are beltdriven on x and y axis and belt/gear/rack on z axis.
The manual says the resolution is 0,0254mm, if i set the steps per to 40 then router overshot 300mm with 5mm.
After testing steps per from diagnostic window i ended up with 39,34193058 on x and y, but im not sure since i dont have good enought tool to measure with. Y axis are set to 35,47196183  and i know this setting are a little wrong.


Today i have counted tooth on the x and y axis pulleys, they are the same.
Motorpulley = 16
Intermediate shaft input pulley = 80
Intermediate shaft output pulley = 10, ø = 16mm
Drive belt 5mm between teeth.

Y axis has belt, gear and rack.
Motor and drive intermediate shaft are 80 / 16, same as for x and y axis.
Gear has 10 teeth, ø=14mm.
Rack has 17,5 tooth in 55mm.

Regards Stein