[FTC]: TETRIX gear specs

[Nate Laverdure]

For posterity:
TETRIX gears have a diametral pitch (DP) of 32 teeth/in, a pressure angle (PA) of 20 degrees, and a face width of 0.250 in.

[Andrew Remmers]

I'm lost as to what the purpose of this was?

[Nate Laverdure]

I thought I explained it pretty succinctly... I needed this information and I couldn't find it on ChiefDelphi or any other obvious place. So after doing the research to find the information, I shared it here for other people to use because I couldn't find a more appropriate place.

[kk052]

thank you for this info i found it usefill

[Nemo]

For posterity:
TETRIX gears have a diametral pitch (DP) of 32 teeth/in, a pressure angle (PA) of 20 degrees, and a face width of 0.250 in.

I think they're actually 0.80 module based on the dimensions of the CAD models that I downloaded. 0.80 module is equivalent to 31.75 pitch, so a custom 32 DP gear would work fine in any case. I'm not positive that the models match reality. If one measures the outer diamter of a 40 tooth gear, then if it's closer to 1.313" it's 32 dp, and if it's closer to 1.323" it's 0.80 module.

[gof]

For posterity:
TETRIX gears have a diametral pitch (DP) of 32 teeth/in, a pressure angle (PA) of 20 degrees, and a face width of 0.250 in.

Adding my thanks for storing this data. Just what I was looking for!

[Nate Laverdure]

Tetrix gears are actually 0.8 Mod (31.75 DP) 20 PA. 32 DP is close enough for most things, but be aware it could affect your center distance. 0.8 Mod is common in rc parts so that may help your search. You may be able to source 20 tooth pinion wire. With a 20 tooth it won't matter 32 DP or 0.8 Mod. Pinion wire is fast just bore and part off to length. Press it onto the shaft. You can also turn a shoulder for set screws if it needs to come apart later.

Before I bought a set of 0.8 module cutters I used 32 DP cutters and metric OD... this kept my center to center distance correct.

Emphasis added. Thanks Dan and Randy for correcting me.