There is lots of previous posts on this here, 14 1/2 deg takes a larger load, 20 is a bit higher precision.Probabally 12 diametric pitch is the largest you may want to go with 20 about the smallest.
Most large commercial gantrys use 14 1/2. Boston gear offer a economical way to go, In Canada they are carried by Bearing Supply.
Al.
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CNC, Mechatronics Integration and Machine Design.
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E. |