Imported Involute Gear Cutter Sets

B

Bill Gruby

Forum Guest
Register Today
If you buy Imported involute cutter sets, look close at the numbers. Most sets I looked at today and marked in reverse order. This can ruin your day in a heartbeat. PLEASE look before you buy. The number cutter and tooth number should be;

#1 --- 135 to rack
#2 --- 55 to 134
#3 --- 35 to 54
#4 --- 26 to 34
#5 --- 21 to 25
#6 --- 17 to 20
#7 --- 14 to 16
#8 --- 12 to 13

Again, be aware the some sets at just flat WRONG. The above cutter number and number of teeth it can cut is written in stone people, don't get bitten. Let the buyer beware.

"Billy G"
 
My set are backwards ie #1 shows 12-13. I looked that up on the web and it seems they say that all the china made cutters are backwards. They number them opposite to American standards. I'm glad you reminded me. Thanx

Roy
 
Hi Bill,
On many old sets I've seen the two versions of numerotation, sometimes from differents countries of origin, here the increasing numbers system is used on module mills but not on clockmaking tools...
 
I wish we could get that changed. I know of three guys in the last week that got burnt. Our member Brian building the 5 cylinder radial was one of them.

"Billy G"
 
I probably have 50 or 60 cutters here. All are marked as I posted them above. I also have some for a dedicated number of teeth which are specially ground to a certain pitch and that's the only tooth count they will cut. Most of my cutters are Morse or Pratt & Whitney. I for one will not buy imported.

"Billy G"
 
The cutters made in Poland are pretty good, and properly marked. China..... well, you just never know what they made them out of. Could be recycled daihatsus or something, and you have noted the numbering systems.
 
Gears that are 14.5 os 20 degree pitch angle use the cutters I posted. To cut metric (module0 gears you use the cutters that are in reverse order. You cannot interchange these cutters as pitch angle and module are two different animals.

"Billy G"
 
Gears that are 14.5 os 20 degree pitch angle use the cutters I posted. To cut metric (module0 gears you use the cutters that are in reverse order. You cannot interchange these cutters as pitch angle and module are two different animals.

"Billy G"

Thank you for clearing that up. I have never seen range cutters for mod gears. We always rented a hob or shaper cutter.
 
I did a lot of research on the reverse order cutters, I thought at first they were a mistake. Not so, they are marked that way purposely so as not to mix mod with pitch angle.

"Billy G"
 
I have researched this issue and have a definitive answer. The difference is Metric and English. The number of teeth remains the same. English is Pitch Angle. Metric is Module. They are two completely different animals. Those Cutter sets on Ebay and elsewhere that we thought were numbered wrong are correctly numbered for Module. They are numbered opposite for tooth count so that you do not pick up the wrong cutter. Hope this clears up the mess.
If there are any other questions on this just ask and I will try to answer them.

English;
#1 - 135 to rack
#2 - 55 to 134
#3 - 35 to 54
#4 - 26 to 34
#5 - 21 to 25
#6 - 17 to 20
#7 - 14 t0 16
#8 - 12 to 13

Metric;
#1 - 12 to 13
#2 - 14 to 16
#3 - 17 to 20
#4 - 21 to 25
#5 - 26 to 34
#6 - 35 to 54
#7 - 55 to 134
#8 - 135 to rack

"Billy G"
 
Last edited by a moderator:
Back
Top