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Location: Regina Saskatchewan Canada
01-15-2018, 10:19 PM
(This post was last modified: 01-15-2018, 10:20 PM by Cross Slide.)
Last weekend I had a friend use my lathe for threading.
We set up the lathe to match the gear change chart. Which we found out is Not Correct. But that's easy to work around now that I know about it.
That part that has me wondering is if my lathe can actually do 13tpi, which is a thread that I will require it to do.
No where on the chart is 13tpi listed.
The incorrect part is that B & C need to be switched.
Is it possible to cut 13tpi with this lathe?
It's a Craftex CX701 lathe
Trevor
Posts: 3,003
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Location: Ontario
The manual might show how to do it with change gears. Just did this on the Hardinge. Even the Summit that cuts an incredible range requires changing out a gear to cut 11 1/2 tpi.
Free advice is worth exactly what you payed for it.
Greg
Posts: 109
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Location: Regina Saskatchewan Canada
01-16-2018, 11:55 AM
(This post was last modified: 01-16-2018, 11:56 AM by Cross Slide.)
Unfortunately the manual doesn’t. It shows the exact same gear changes as the panel on the machine I pictured. I did happen to see in a YouTube video a lathe that looks exactly the same as mine. Precision Matthews PM-1127VF-LB. That manual is also exactly the same except for two things. They show the correct TPI for B & C. As well as a gear setup that will do 13tpi. That lathe comes with a 65 tooth gear where mine does not. I contacted them by email but they could not tell me if the gear would fit mine or not since it’s not their model.
Posts: 3,003
Threads: 51
Joined: Apr 2012
Location: Ontario
Maybe contact Busy Bee, see if they can supply the gear. 13 tpi is fairly common.
Free advice is worth exactly what you payed for it.
Greg
Posts: 2,328
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Location: La Libertad, Philippines
Check with your local industrial supplier who carries gears, Boston Gears if possible and have them order you a 65 tooth gear. You'll have to finish the bore and cut the keyway, but it will be a lot cheaper than from a machine tool dealer/supplier. Since you have a lathe you have everything you need to finish the gear, including cutting the keyway. Here is how to cut a keyway on the lathe:
https://www.youtube.com/watch?v=yQcgLDZLMsk
Same way I was taught in 1973 at the Navy's Machinery Repairman School.
