Threading to a shoulder

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

f350ca
Posts: 260
Joined: Wed Dec 21, 2011 6:10 pm
Location: Calabogie Ontario

Re: Threading to a shoulder

Post by f350ca » Thu Jun 15, 2017 8:34 pm

The Hardinge HVL has a travel stop on the carriage for threading. You leave the 1/2 nuts locked. When it hits the stop the carriage stops and the cutter makes its own relief groove. A quick retract on the compound moves the tool back, you flip a leaver to reverse the carriage which stops on a back stop. Set your next cut, flip the quick retract back and engage the forward direction. Great for threading to shoulders or the quick retract will work backwards for internal threading in a blind hole. They advertise the repeatability of the stop to .003 but measures better. They recommend not threading over 1000 rpm.
There is a 2:1 reduction off the spindle to a 2 eared dog clutch so it doesn't mater when you engage the lead screw, your always lined up in inch or metric.

Greg

Patio
Posts: 1252
Joined: Wed Oct 06, 2010 3:14 pm
Location: Centralia Wa

Re: Threading to a shoulder

Post by Patio » Sat Jun 17, 2017 1:03 am

I have a Cazeneuve HBX360 that allows threading to a stop. It does not say what the repeat ability of it is, and I have never measured it. There are 3 built in longitudinal stops. One that is mounted on the bed, making it 4. The machine is suppose to have a stop for the right hand side of the apron that will mount on the bed, but it did not come with the lathe. I hope to make one someday.
There are two stops on the carriage for threading. One for traveling in and the other for limiting the pull out, to make things faster. These are both micrometer stops and can be used when plunge cutting a thread.
The stop that mounts to the bed, on the left hand side is a micrometer stop also.

When threading, I use the cross slide stops to set a 0, with the handle of the cross slide at 9:00, and use the compound to advance the cut and set the left, bed mounted stop according to the shoulder I am threading to. I also like to pull out just as the stop occurs, like while threading on a normal lathe. I could leave it to cut its own relieve at the stop point, but I don't. I do use the left hand stop, to move the stop point a few thousands, to the right, each time I advance the compound while cutting. Other wise the cutter would sooner or later run into the shoulder before hitting the stop.

On another note, the lathe can cut a 1/4 thread, or 1 revolution in 4". I have not tried that yet either. :)
I am looking to find a video camera, to borrow for an afternoon, to shoot some video of the lathes many unique features.
Live for the moment!
Prepare for tomorrow!
Forgive the past!

spro
Posts: 7899
Joined: Mon Feb 20, 2006 11:04 pm
Location: mid atlantic

Re: Threading to a shoulder

Post by spro » Sun Jun 18, 2017 5:57 pm

Even a reply from me can show some anticipation to that video. I think it will be astounding to many us, especially those who haven't followed your journey with that special lathe. Knowledge and enjoyment.

Post Reply