# Gear identification and sizing

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#### coyotebgone

##### Member
One of these gears is very difficult to find. But brings me to a question. If I decide I want to make these gears, after I learn how to use a dividing head. Does the name of these gears define the information I need
to make them. Diametrical pitch, diameter etc? Example, top gear, the two companies use 32 and 48 in the name, meaningfully?

The part number says that the pinion is 32 diametral pitch with 24 teeth. The gear is 32 D.P. with 48 teeth.

I was going to guess this from the last five digits in the part numbers: 1B 2-N32048 and 1C 2-N32024.

Coyote, once you know the DP and number of teeth, you have almost everything you need to buy gear cutters. If you were matching these to an existing gear, you would need to know the Pressure Angle (PA - either 20° or 14.5°) ... but if you are cutting two gears that only need to mesh with each other, then you can choose either PA based on availability and cost of cutters.

It looks to me like the only 32DP gear cutters that are available are 14.5° PA. Here is one of the very few examples I can find:

https://www.victornet.com/detail/GC14-32-4-7/8.html
Note that you would need two cutters, the #3 (to cut 48 tooth gear) and a #5 (to cut 24 tooth gear).

Note also that, at least for me, it is much, much easier and cheaper to source metric gear cutters with 20° PA. The problem is, if you switch to metric, you would need to change the placement of your cam gear.

I have cut DP gears using MOD cutters. A 32 DP has a tooth depth of .067 and a .8 MOD gear has a tooth depth of .070. Just use the DP dimensions with the MOD cutter. This is low speed, low load gears and it is close enough for this type of thing. This is not a space rocket.

Yes, a good point. The closest module would be .75, but I am not seeing any cutters in that size. I do see .7 and .8 module.

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