[sanddrag]

We made two identical gearboxes for our robot using Martin .5" face width, 20*PA 20P gears. (TS Series) One gearbox turns just incredibly smooth. The other one turns REALLY bad, it binds like crazy. They were both made on the same setups in the CNC. We tracked the problem down to one gear, and the problem follws the gear when we put it in the other box.

We are thinking maybe the gear got made with a 14.5* pressure angle by mistake? I know this is highly unlikely but could this have happened in Martin's manufactuing line? Would a 20*PA mating with a 14.5*PA still turn but bind bad, like ours does?

See, Martin's 20P 14.5*PA gears are only 3/8" face width, all our (20*PA) gears are 1/2" That's why I'm thinking this is highly unlikely. But, I do think it is possible because while the gear does bind a little more in one spot, it is "crunchy" all the way around while meshing.

The mesh is a 30:45, and we believe the 45 is causing the problem, however we "clocked" the tight spot to the 30.