Tailstock Threading Die Holder

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Robert
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It's about time I got around to making this. After looking over a few designs, I decided to emulate this:

1625365039780.png

I had a piece of 1" 1144 on the shelf that I thought would make a good MT2 taper shaft.
I set my compound against a known good MT2 taper held between centers. Then I cut the taper holding the stock between centers.

1625365273228.png

The straight part is turned to 0.749. I will ream the holder to 0.750.

The holder was made from 12L14:

1625365330447.png

1625365347725.png

1625365363828.png

It slides perfectly. I still need to put in a set screw to hold the die and add a lever handle. I plan to make this reversible so I can have a 1" die on one end and a 13/16" on the other.

Any comments on handle length? Should it clear the lathe bed or purposefully interfere with it?

Robert
 
Nice job.

For what it’s worth, I bought one like the pic and the little handle is actually not bad, especially the plastic knob. I rest that knob on my compound(it’s in parallel with the bed) and let it slide along the compound after I get the die started. My problem with it is the cut down the center of the die holder not leaving much meat for the little handle to thread into. I have two different die holders for my different die holders along with a nice tap holder that needs a handle so I plan on making an adjustable handle almost in the shape of a micrometer that can grab the different die holders and tap holder on both sides of the barrel. I also want to make a bigger holder for my Greenfield screw plates to fit into. So that one handle would be able to grab all the different holders and have a Delrin or UHMW knob on the end so it would glide on the compound and not mar it.
 
I recently made one of these as well. It's one of my first lathe projects and a good learning experience. I pretty much followed some plans I found in the downloads section here on Hobby Machinist.

I made the handle ~3.5" long in keeping with those plans, but a touch longer wouldn't hurt.

Nice job on the MT2 taper. I cheated and used a MT2-JT3 arbor that I drilled and reamed to 1/2" and then loctited in some 1/2" drill rod.

One thought I have regarding yours is that with a 3/4" hole bored in it there isn't much material left for a register for a 13/16" die. I think a 1/2" bore is adequate, as I've never seen a 1" OD die for a larger thread than 1/2-20....I figure I can single point thread any larger diameter material.
 
Good tips guys. I like the idea of being able to rest the handle on the compound. I will use an appropriate length. Yeah, I just winged it at .750". I could still hold a 13/16 but I plan on buying all 1" dies going forward. Anything larger than 1/2 get single pointed.
I am trying to come up with a way to mount a 3 jaw Sherline chuck on this also. That will allow me to hold any size hexagonal die. The Sherline is a 3/4-16 thread.
Robert
 
For hex dies, you can always buy a cheap hand hex die holder from harbor freight/princess auto and turn the outside to fit your tail stock die holder. Then you have an additional die holder adapter.

Sent from my SM-T500 using Tapatalk
 
I don't see where HF sells hex holders? How about machining down a socket.
Why do most die holders have 3 or 4 screws? My round dies have one divot for engagement? I would think a single thumb screw would be enough?
Robert
 
Last edited:
It's about time I got around to making this. After looking over a few designs, I decided to emulate this:

View attachment 371048

I had a piece of 1" 1144 on the shelf that I thought would make a good MT2 taper shaft.
I set my compound against a known good MT2 taper held between centers. Then I cut the taper holding the stock between centers.

View attachment 371049

The straight part is turned to 0.749. I will ream the holder to 0.750.

The holder was made from 12L14:

View attachment 371050

View attachment 371052

View attachment 371053

It slides perfectly. I still need to put in a set screw to hold the die and add a lever handle. I plan to make this reversible so I can have a 1" die on one end and a 13/16" on the other.

Any comments on handle length? Should it clear the lathe bed or purposefully interfere with it?

Robert
If you spend 150 on a used geometric style die head, chasers on ebay run about the same as quality round dies. With a die head you get great threads and the ability to adjust from class 1 to class 5 threads. A die head opens automatically at the end of pre-determined point.
 
...
Why do most die holders have 3 or 4 screws? My round dies have one divot for engagement? I would think a single thumb screw would be enough?
Robert
With 3 screws, the middle one is used to force the slit in the die apart to loosen up the thread cut while the ones on either side of center hold the die in the holder.
 
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