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How to cut threads on a lathe.
tilly819 - 6/6/20 at 10:01 AM

Hi all,

I had to do some screw cutting on the lathe the other day so i'v put together this little 'how to' video. Hopefully it will help anyone just getting started with screw cutting on the lathe.


liam.mccaffrey - 6/6/20 at 11:24 AM

Nice video, really enjoyed.

Have you checked out Joe Pi's threading videos? Runs the lathe backwards with the tool upside down so for a RH thread you can feed AWAY from the chuck.

53Stix - 6/6/20 at 01:02 PM

Great video, and pitched at the right level IMO

JC - 6/6/20 at 01:31 PM

Great video. I've never used a metal cutting lathe but it's on my Christmas list of things to get/try! I always wondered how threads were cut!

jps - 7/6/20 at 09:28 AM

very interesting, thanks for sharing.

tilly819 - 7/6/20 at 09:26 PM

Thank you all, I'm glad you enjoyed it.

02GF74 - 9/6/20 at 09:07 PM

what's the story with the number dial? For M14 you said engage when any number 1 to 8 lines up - what would happen if you engaged at 8 for first pass then say at 7 for second or engage at halfway between 7 and 8 for both passes?

steve m - 11/6/20 at 05:49 PM

Now that my car has gone, I have no interest in having a lathe, but I did find the tuition very interesting, as I would never of known how to of cut a thread even if I did have a lathe

However, my thread cutting technique with a pillar drill, vice and dies, was pretty good !!

tilly819 - 13/6/20 at 08:58 AM

quote:
Originally posted by 02GF74
what's the story with the number dial? For M14 you said engage when any number 1 to 8 lines up - what would happen if you engaged at 8 for first pass then say at 7 for second or engage at halfway between 7 and 8 for both passes?


8 on the first pass and 7 on the second would be fine.
I don't think you physically can engage half way between because the bit that that goes into the lead screw doesn't line up.

Depending on the pitch of the tread (for metric anyway) determines which numbers you can use on the thread dial indicator. you can use any of the ones on the list from the lookup table in any order you like. Just don't use one that isn't on the list or you end up cutting a different thread.

Hope that clears that up for you. Thanks for watching.

Dingz - 13/6/20 at 12:57 PM

Thanks for that it took me back to being an apprentice, but most of the lathes in the workshop had change wheels so you had to spend a while doing the sums, then swap the gears over to hopefully, get the right pitch.