Gear cutting problems

Perhaps the problem could be solved by finding the correct USA made cutter and buying one; I have quite a few cutters, have not looked for that particular one, but LMK if you would like me to do so.
 
I may take you up on that...but I'm already into these cutters for a few bucks and would like to figure out which one, if either, is correct. I bought these from Travers. I called them to speak with someone see if they have had any similar issues. All the techs were gone for the day and I was told I would get a call tomorrow .

I was looking at a set of Chinese 16DP cutters I have. They only issue I have with those is how they're numbered... the listed tooth range on each cutter is correct just the number of the cutter is opposite of American made ones.

Correct me if I'm wrong, but in looking at the cutter profile would I be correct in thinking that the steeper or straighter the sides of the tooth the higher the tooth cutting range would be? One of the photos I posted was a view of the profiles of each of the cutters and one seems steeper or more straight than the other.
 
Yes, the straighter the angle, the higher the tooth count, the #8 in USA, would be 134 to rack, the #1 would be 12 - 13 T, just the opposite in china and europe. My cutters, if I have the right ones would not be particularly pricey. I have two sets from tiny to #3 DP
 
I have checked my calculations and the depth of cut for a 20° or 14.5° are the same. The gear blank diameter is also the same.
The cutting depth = 2.16 X Module (mm)
The module = DP / 25.4
So for a DP cutter it would be 2.16 X DP / 25.4 = 0.0850 X DP (")

The larger the teeth count, the more the cutter will look like a rack cutter having straight edges.
If you have a 3D printer, you can print a gear (just a few teeth) to compare
Most CAD software can design gears. You could print such a gear to compare.

Edit:
The gear ranges of a 20° and 14.5° cutter are different.
 
Also, one can buy gear gages, perhaps a good idea if you plan to do much with gearing, the USA version (DP) that I have has both 14 1/2 and 20 degree PA, the module one has only 20 deg PA, I got it from Metric and Multistandard Components Corp.
 
The cutter I suspect the most is the one labeled #6. On it is " Z17-21", which I think is odd because I've only seen that tooth range listed as 17-20...not 21. The other thing is the "0.1197" marked one it. I cannot figure out what that refers to. Is there a course DP that would have that for a depth of cut? I tried converting that to inches thinking maybe it's the metric value for depth of cut, but that comes out to .0047" and that can't be right. So, I'm lost on that. It also has a "14" stamped into...again, no idea.
 
Normally cutters are marked with the cutting depth, PA, DP (or module) and gear range.
That 14 could be part of the PA (14.5) or the teeth count.
0.1197 can only be the cutting depth ("). In that case it would be a module 1.4 (35.8DP) gear cutter.
 
So far as I know and have seen, the decimal figure is full depth of cut on DP cutters, expressd in inches.
 
Which why I think there is something wrong with that one cutter .1197 is way to deep for 32P
 
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