Hi, for my cnc router project I need to make three tooth belt pulleys but I am not quite sure of how to go about. I have made a kind of poor man's dividing head using cog wheels from my lathe which I believe is quite accurate. I don't seem to succeed with making a pulley that fits the belt. I get it just a few percent wrong. Now, I don't have any data for my belts cause I scavenged it from an old printer. Measuring the tooth division I get about 2.036 mm. I guess it's a 0.8 inch division which seems to be a common Standard. What outer diameter should I calculate to use, is the fact that the belt is bend around the pulley affect the division? There must be a offset position inside the thickness that the bending does nor create compression, nor expansion and that is where I should calculate the pulley diameter from? Something like d = ( n-cogs * division) / PI + 2* offset. Any one knows?
Thanks, Lars