help with thread chart on lathe

All discussion about lathes including but not limited to: South Bend, Hardinge, Logan, Monarch, Clausing and other HSM lathes, including imports

Moderators: Harold_V, GlennW

Post Reply
Eyalzimer
Posts: 2
Joined: Sun Sep 12, 2021 9:50 am

help with thread chart on lathe

Post by Eyalzimer » Mon Sep 13, 2021 3:02 pm

Hello,

I have an old lathe at my work that we used for very basic and I want to understand more about it:) Its pretty old one and I couldn't found any manuals.

There is a chart for Thread and how to do the setting, on one side of the chart H/mm and on the other is 1"/H I think its pitch in mm and TPI but on any other chart on the internet(converting pitch mm to TPI) it isn't the same number. Is there a different calculation?

Also there there is a knob with 3 different state that are not connected to the chart, one with Metric and to other that erased.

Can someone please explain me the chart and the knob:)
Attachments
IMG_20210912_154130.jpg
IMG_20210913_153223.jpg
IMG_20210913_153218.jpg
IMG_20210913_153215.jpg

John Evans
Posts: 2255
Joined: Tue Jan 20, 2009 9:33 pm
Location: Phoenix ,AZ

Re: help with thread chart on lathe

Post by John Evans » Mon Sep 13, 2021 6:16 pm

You set the knob to either metric or inch ,that should change the gear train internally to cut the correct thread using the appropriate chart and settings. What make is the lathe and country of origin?
www.chaski.com

Eyalzimer
Posts: 2
Joined: Sun Sep 12, 2021 9:50 am

Re: help with thread chart on lathe

Post by Eyalzimer » Mon Sep 13, 2021 11:09 pm

Thanks for replying

I think the lathe is from Italy, but it is very old (more then 40 years).
There is on the lathe knob that i can put the gear setting for the chart but I don't sure how to read it since the H/mm and 1"/H isn't matching...

John Evans
Posts: 2255
Joined: Tue Jan 20, 2009 9:33 pm
Location: Phoenix ,AZ

Re: help with thread chart on lathe

Post by John Evans » Tue Sep 14, 2021 11:42 am

Well I THINK to cut 16 threads per inch you then 1 set the knob to the inch position 2 set a second knob to "A" then 3 set a third knob to "1" By the way 40 years is not all that old. Is there a makers name on it ? If so post it please. I use to work part time at a friend of mine machinery dealership, and we got used lathes in made all over the world. And the controls were all over the place as to function. If your lathe was in front of me I don't think it would take me long to figure out how to make it work. In your first picture at the far right I can see some instructions for positioning some of the feed gears for various feeds ,some of those may be needed to be shifted to cut a particular thread.
www.chaski.com

Post Reply