Author Topic: Need help with cutting a thread in a lathe...  (Read 664 times)

Offline Kinkajou

  • Jr. Member
  • **
  • Posts: 13
Need help with cutting a thread in a lathe...
« on: June 28, 2017, 12:15:22 PM »
Good morning.
I have been using a very simple Grizzly 3 in one machine, you know, a small footprint equipment that has Mill/Drill and lathe. When I got it I did not know of all the limitations, I consider myself a self taught noob and try my best with what I have.

So I need need advise. I have read books and watched you tube instructional videos which have been great. But almost everyone has the same procedure regarding thread cutting on a manual lathe. They start by the tool which has to have specific angles and they use the compound on the lathe.
Problem is that I do not have a compound on the lathe that has a dial, so I can not move the tool in a diagonal fashion.

How can I solve this? Should I only use the X and Y feed on the lathe?
I can not make a nice part so far, but I do not want to do it with a  Tap an Die because it always end eccentric.

Thanks in advance for the patience and advice.


Offline wheeltapper

  • Sr. Member
  • ****
  • Posts: 342
  • Country: gb
  • Spixworth Norfolk
Re: Need help with cutting a thread in a lathe...
« Reply #1 on: June 28, 2017, 12:52:34 PM »
It's quite possible to cut a thread without using the compound / topslide.
it only comes in handy when cutting a deep thread as by turning the topslide to the thread angle the tool only cuts on one side.

for smaller threads plunging straight in works.
in fact I removed the topslide from my import lathe because it suffers from weeble wobble itis. i only fit it to turn a taper ( and it's not much good at that either.

you do however have to have the correct angle on the tool which also has to be square to the work.

Roy.




I used to be confused, now I just don't know.

Offline John Stevenson

  • In Memoriam
  • Hero Member
  • *****
  • Posts: 1645
  • Nottingham, England.
Re: Need help with cutting a thread in a lathe...
« Reply #2 on: June 28, 2017, 01:52:36 PM »
A very good reply. I always do it that way
John Stevenson

Offline Kinkajou

  • Jr. Member
  • **
  • Posts: 13
Re: Need help with cutting a thread in a lathe...
« Reply #3 on: June 29, 2017, 12:33:40 AM »
Thanks Roy, the same applies to internal threads? I will try it tomorrow.

Offline 69CamaroZNut

  • Jr. Member
  • **
  • Posts: 7
  • Country: us
Re: Need help with cutting a thread in a lathe...
« Reply #4 on: October 04, 2017, 07:16:52 PM »
I have a Harbor Freight 3-in-1 machine.  If your machine is 8" to 9" to center of the chuck you can purchase any of the HF or Grizzly 3-in-1 compound rests/slides with the calibrated feed screw in Inches or MM dial for your lathe.

John
« Last Edit: October 04, 2017, 08:11:26 PM by 69CamaroZNut »