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View Full Version : Threading stop on Grizzly lathe (question)



seatlanta
01-11-2007, 06:21 PM
I have a new Grizzly 12x24 lathe and want to make a threading stop. In the few plans I've found, it looks like the stop clamps to the rear crossfeed ways, so that it stops travel when the crossfeed is moved into the workpiece.

That's fine, but the ways on my lathe are not exposed except at the front (near the operator), so it looks like I need to find a different method.

I want a positive stop for the crossfeed to hit against when I move it into the workpiece that I'm threading.

I'm sure there must be lots of plans and ideas out there, but I've not been able to find one that suits my lathe--either that or I'm not understanding what I'm seeing.

I can design and build it, but if someone else has some experience, maybe it would help me avoid problems.

I'd appreciate some suggestions.

Thanks.
James (seatlanta)

John R
01-11-2007, 07:16 PM
You can arrange a stop on the near side of the cross slide ....tap a hole in the end of the cross slide aligned with a clearance hole in the clamp then adjust a screw thru the clamp into the cross slide for the correct stop position and secure it with a lock nut.
John R

rws
01-12-2007, 08:43 AM
A positive stop for the saddle that does not disengage the half nuts makes me. It makes nervous. If you did not disengage the half nuts at the right time, things will start to crunch. There has been linkage designed that would throw the half nut lever, and maybe even lathes themselves that will do it. I use a 2" travel dial indicator with a mini-mag base set on the ways that rides the saddle. I zero the indicator where I want to stop threading, and watch it while threading. Makes it easy to pull out of the thread the same place each time.

SGW
01-12-2007, 08:52 AM
RWS, this is a stop for the cross-slide, not the carriage. If it was the carriage, yes, I'm not sure it would be a good idea! But the idea is to put a stop on the cross-slide to simplify positioning the tool at the correct depth. I've always just used the dial reading, but stop would be faster.

QSIMDO
01-12-2007, 09:22 AM
I've been eye-balling the follow rest mounting holes on the left rear of the carriage for that and other uses but I've got the 11x26.

Maybe something from there if yours is similar?

JCHannum
01-12-2007, 10:49 AM
This is a South Bend cross slide stop;

http://cgi.ebay.com/Southbend-Heavy-10-cross-slide-stop-threading_W0QQitemZ110076335237QQihZ001QQcategoryZ 25295QQssPageNameZWDVWQQrdZ1QQcmdZViewItem?hash=it em110076335237

They are simple enough to make, just a two piece flat bar to clamp to the dovetail. The capscrew in the center is used for fine tuning the stop.

This is the stop on the front of the carriage on my Sheldon. It swings out of the way when not in use. I usually remember it's there after I am done threading. It is just natural for me to return the carriage and rezero the cross slide at the end of the cut.

http://members.aol.com/jchannum/stop

C - ROSS
01-12-2007, 12:35 PM
Wish I had a picture for you (still in Rochester recovering) I made two stops for my Griz. 12x36, one for external threads and one for internal. The external stop bolts on the back side of the saddle and has a threaded rod used as a stop against the cross slide. The internal is just the standard way clamp.

Ross

dp
01-12-2007, 03:28 PM
This is an idea I'm looking at for my Grizzly:
http://vts.bc.ca/metalshop/tstop/tstop.htm

Tin Falcon
01-12-2007, 05:38 PM
DP: Nice design looks like a copy of the South bend stop as pictured on lathes.com . Somthing to add to my to do list.
Tin

IOWOLF
01-12-2007, 06:00 PM
Wouldn't this only work with a Clutch type cross feeds?Gear type things will go crunch as someone said.
But Hey It's not MY lathe.

BadDog
01-12-2007, 06:09 PM
You don't power cross feed on threading, so why would it matter?

I love the integral threading stop on my 11" Rockwell, but it's integrated into the dial, so it wouldn't be easy to adapt to another lathe.

Still, seems you could mount something on the back of the apron, something like the vise stops used on milling vices, and then use that to provide a hard stop on the back face of the cross slide...

seatlanta
01-12-2007, 07:14 PM
Many thanks for all the suggestions.

My lathe looks something like the one in JCHannum's photo, and that's the type of threading stop I was looking for.

It looks like it's easy to make. That means I can destroy it more quickly than a complicated project.

When I get it made (and working), I'll post a photo.

Thanks again
James (seatlanta)

IOWOLF
01-12-2007, 07:28 PM
ooops, I reread the post,I was Mistaken.

Boucher
03-22-2007, 11:35 AM
I am having trouble understanding what I am seeing. I think there is a better arrangement. Rudy's Video on threading shows a better way. You bump the stop going back in with the cross slide. This mechanically sets the dial back to its zero position. If you back out more than one turn it is of no matter. The down side of this is that after cutting most of the thread depth using the compound you may want to make the last finishing cut straight in which requires moving the stop.

Spin Doctor
03-22-2007, 02:00 PM
One more reason to design a Hardinge style Quick Retracting compound for threading. None of the BS of backing the tool out with the cross slide.

Euph0ny
04-02-2012, 02:35 PM
You might find these two "Tubal Cain" videos helpful. The lesson is about how to measure and cut dovetails, but the project being made is a threading stop for a lathe cross-slide.

Its function is explained in a segment towards the beginning of the first clip, and demonstrated at the end of the second.

Tubal Cain Tip # 76 http://youtu.be/6S_iOU0C-Ug

Tubal Cain Tip # 77 http://youtu.be/xT2oACFlB0c

elginrunner
04-02-2012, 07:19 PM
Euphony - that would be just the ticket. If I only had a mill... :(

JCHannum
04-02-2012, 08:37 PM
Five year old thread resurrected for some reason.

oldtiffie
04-02-2012, 08:56 PM
Odd - never felt the need for one.

I just use a good dial indicator on a good magnetic base with the indicator on the tool post and the base on the carriage.