AGMA 236.04 -- Backlash Classes?

[tpederzani]

I occasionally deal with some of my company's legacy products that have gear quality classes called out per AGMA 236.04 (e.g. "Commercial 1" thru "Commercial 4", "Precision 1" thru "Precision 3"). In fact, all of the ones I've seen are "Commercial 4C". The table giving the corresponding TTCE and TCE is in many places (including the Gear Handbook by Dudley and AGMA 390.02). I have not seen an explanation that would cover the "C" at the end of my callout. Does anyone know what this means? (It would be nice if it was exactly the same as the backlash class in 390.02, because I have that spec.)

 

[mfgenggear]

I google this

http://www.americangearinc.com/quality.html

mfgenggear

 

[tpederzani]

Right, that's the table that gives the TCE and TTCE of each of the AGMA 236.04 classes. However, I'm looking for something like Table 12 ("Backlash Allow and Tolerance for Fine-Pitch...") in AGMA 390.02.

Oh, I just found that I do have a copy of such a table, in Gear Design and Application by Nicholas Chironis. I'll attach it here, since I didn't find it on the Internet.