80/63 transposing gear help

[jhinze]

So the more I look and read, the more confused I get. I just picked up an 80/63 transposing pair for my 10L.. I need to cut some metric pitches (0.5mm).

Please correct me if I am wrong... but with that transposing gear, I can use the following to figure out my tumbler settings for the pitch using the following:
.019685 (0.5mm pitch) / 1.27 = .02499995

To find tpi:
1/x = .02499995
x = 1/.02499995
x=40.00008

so 40 tpi with the 80/63 pair to cut a 0.5 metric pitch?

Is there a reference chart, list of stud gears I may or may not need, or better formula? (Assuming of course I'm not off my rocker )

Thank you in advance

 

[500mpxlcameraguy]

You should be able to use the SB metric chart which shows the tumbler settings with a 127/100 gear. It’s the same ratio so the settings shouldn’t change. I’m sure you will get confirmation from others. I’m using a chart for an SB9A with a 37/47 gear with success So the 80/63 should just be more accurate over a longer thread length.

 

[jhinze]

You should be able to use the SB metric chart which shows the tumbler settings with a 127/100 gear. It’s the same ratio so the settings shouldn’t change. I’m sure you will get confirmation from others. I’m using a chart for an SB9A with a 37/47 gear with success So the 80/63 should just be more accurate over a longer thread length.

Thank you! Might you point me to where I might find the chart?

 

[500mpxlcameraguy]

I only have information for a 9A which I got on an on line search, maybe someone else can help you out.

 

[SBLatheman]

I only have information for a 9A which I got on an on line search, maybe someone else can help you out.

The chart for the 9”/10K and the Heavy 10 are the same

 

[500mpxlcameraguy]

I just found the chart on line. Look for Brett Nordgren metric chart for a useful chart that I have used in the past, since we now know that the 10 uses the same chart.