Posted by Colin on November 03, 2009 at 08:57:39:
In Reply to: Please help Gear calculations posted by Andy on November 02, 2009 at 06:30:17:
Your problem is a bit of a mystery.
If we take the tooth depth of 6.6mm this is exactly the standard depth for 3mod.
However using the O/D and 32 degree helix angle, and all the gear sizes, the module is very close to 2.75 ( even closer if I use 30 degrees which is more likely). If this were the case, however then the tooth depth would only be 6.05mm if the gears were cut. Maybe they are ground or shaved gears which have extra depth, althogh 0.61mm is a lot.
This anomaly could be explained by various profile shifts but it is still very strange.
May I suggest that you try meshing any two of the gears ( or more combinations) on the bench and measuring the centres- this would be a good indicator of module etc.
Alternatively you could measure across pins or calipers.