Threading jig almost ready for prime time

[TimR]

Well, back about 4 or 5 years ago I bought a couple pieces of 3/4” all thread in both 10 and 16 tpi as well as some nuts and a 60 degree cutter. Sat in a drawer and then packed away for our move.
I’d always thought it would be a nice alternative to the traditional hand threading tools. Can’t believe how quickly I got this together in a couple hours. Still need to make a threaded support block for the 16 tpi bar. A lot of folks just use nuts in a vise or welded to a bar for this, but tapping results in having less play. I don’t have another block of nylon so will try some hard wood like red tip photinia and see how it holds up.
Will be sure to post something once threaded!

 

[Tony]

How big a piece of nylon do you need?

 

[TimR]

Around 2x2x3 would do it

 

[Tony]

I've got 1" thick pieces, I could cut you a couple of 3" pieces if you could use that.

 

[TimR]

Thanks Tony, I’ll see how using wood works out, should be fine. If I get desperate could always use a piece of lignum vitae, they use to use it for bearings in ships!!

 

[Smitty]

That is a very nice threading rig. I think I want to try to make one. Where did you get the cutter? Also, how do you attach the board that holds the vise to the lathe?

 

[barry richardson]

Wow that looks like a cool rig! Don't know anything about threading jigs, will it make both male and female threads? Any size limitations of the turnings?

 

[Nubsnstubs]

Wow that looks like a cool rig! Don't know anything about threading jigs, will it make both male and female threads? Any size limitations of the turnings?

Good questions, Barry. It looks to me if the opening isn't too large to exceed the cross slide limits, male threads are possible.

Tim, will that cutter cut forward and reverse?? ............. Jerry (in Tucson)

 

[TimR]

That is a very nice threading rig. I think I want to try to make one. Where did you get the cutter? Also, how do you attach the board that holds the vise to the lathe?

Thanks Smitty. I got my cutter years ago from WT Tool, you can get anywhere machine tool stuff is sold, even Amazon.
So, I bolted the vise to a piece of mdf. This gives stability and allows me to bring the mdf up against the banjo as a reference to return to when moving it in and out of the way to checkfits. The piece of tape provides a crude sideways reference.
For now, clamping one place is enough to hold it when pushed hard against the banjo.

 

[Smitty]

Thank's, Tim. I will seriously try to make one. Looks great.

 

[TimR]

Wow that looks like a cool rig! Don't know anything about threading jigs, will it make both male and female threads? Any size limitations of the turnings?

Thanks Barry. Currently on my mini lathe it looks like the biggest piece I could get in would be about 9-10” tall with most of the jig hanging off, but most of weight still on the lathe. Diameter determined by lathe, 12” on this Delta.
However...this brings up an issue that needs careful addressing because of the nature of the parts used. Ideally, the threaded rod would be machined with a feature allowing true mating to the chuck thread adapter with minimal runout to avoid “wobble” especially on longer pieces. With small boxes, just a couple inches tall, these errors aren’t as noticeable.
I recall sending back several of the rods because I’d roll them on a flat surface and could see they had ever so slight bend, but enough to cause an issue.
The other thing to be cautious of is moving from one chuck to another. I did a small test block and was going from my big lathe to the Delta, and made sure I was using similar jaws so the little bit of crush in the tenon would be somewhat equal, otherwise, that would cause your threads to be eccentric to your form.

 

[TimR]

Thank's, Tim. I will seriously try to make one. Looks great.

If I didn’t already have the xy table/vise, I would fabricate it. Should be able to google something like that done. Oh, and don’t really need x and y...only need to go sideways to advance the piece into the cutter for thread depth.

 

[TimR]

Good questions, Barry. It looks to me if the opening isn't too large to exceed the cross slide limits, male threads are possible.

Tim, will that cutter cut forward and reverse?? ............. Jerry (in Tucson)

Both male and female threads are done.
The cutter only cuts one direction, forward.

 

[TimR]

Spindle adapters

 

[TimR]

@Tony , the red tip photinia worked fine, good clean threads and I now have s separate setup (bar, rod, adapter) for fine thread (16 tpi) too. This fine setup feels a lot smoother and I can’t see any wobble at all, so I think I’ll work on making an acorn!

 

[Tony]

Pic of acorn?

 

[TimR]

Patience my friend

 

[TimR]

Actually, I finished threading both halves with the 16tpi setup. Worked smooth. Will shape an acorn out of it tomorrow...maybe.

 

[Tony]

 

[TimR]

Ok ok, @Tony here’s the pic...so it really happened!