Greenfield GTD Tap Handle No. 5 5B Thread pitch and Diameter of Jaw

[russevertz]

I have a Greenfield GTD Tap Handle No. 5 (also includes "5B"). It is currently missing the moving jaw. It has a reverse thread that threads into the handle.
Curious if anybody has one of these and can pull the moving jaw out and share the Thread pitch and Thread Diameter?
The fixed jaw comes out after releasing the set screw and then the moving jaw has enough travel to screw out of the handle.
I have been able to get a Drill Chuck retaining screw to thread in but it seems too loose. It is 6mm-1.1 pitch Left Hand Thread. This is close to 1/4-23.
Mr. Pete published the specs for the No 6 or 7 on a video and it was not a standard thread.

Hopefully someone on here has one and will help me out.

Thanks,
Russ

Greenfield GTD Tap Handle No. 5 5B Thread pitch and Diameter of Jaw

 

[djc]

Please confirm that the part you do have contains a female thread.

If so, turn a piece of wood to 1/4" diameter and screw it into the female thread, remembering that it is left hand drive. Once removed, you can check it with a pitch gauge.

Put a line of wax or putty or blutak onto a rod that will enter the hole. Push it in, squash it onto the threads, remove it and check the pitch.

It is highly unlikely that the screw you have is 1.1mm pitch.

There is a 1/4-24 UNS thread, but that is a pure guess.

Really worst case: drill out the threads in the handle. Plug the hole (loctite the plug in). Redrill and tap 1/4-UNC or 1/4-UNF LH. Make jaw to suit.

If you have a 3D printer, make some likely male threads and try each in turn until one fits. A plain 3D-printed rod could be used instead of the wood above.

 

[russevertz]

Thanks for the ideas...I will try the dowel trick.

Looking back I only calculated 1.1mm and 23 tpi but I am guessing it is 24 or 1mm. Since it is an old US made tool, I am leaning towards the 1/4-24 tpi.

Left hand threaded bolts are hard to find...then you add a wacky pitch and it is harder! I can try single pointing it but I have problems on little bolts. The body seems to get unstable and bends...ending the operation.

Thanks again.

Still hoping somebody can give me the real measurements though.
Russ

 

[krypto]

The GTD tap handles changed over the years so only you can determine what thread you will need. The chances of an old American tap handle using metric threads is approximately 0.001%.

You will need to use the lathe to cut the oddball LH thread. That's why we have expensive toys in our shops.

This is a small, old General tap wrench I repaired a few years ago by replacing the threaded section at the end of the handle which was 8-32 LH, a good deal smaller than what you are talking about. You can do it!

https://doug.sdf.org/2022/05/20/repairing-a-general-170-tap-wrench/

 

[russevertz]

Thanks for sharing. I was thinking of using a long bolt...but I have cap screws too.
I think this is the opposite of mine as the threaded rod comes off of the jaw...which is lost. Butterfield uses the same as your General arrangement...

After jamming some wood in there, I am guessing 1/4-24 which does exist. More in taps than in bolts...

It is funny how close the 1.0mm is to 24 tpi. The 6 mm diameter is too loose for my liking though.

Perhaps I will try single pointing it. I have done a few larger items with success but not many. The next trick will be machining a lathe blank down with carbide...unless I need to use a Dremel with abrasive?

Thanks again for the response.

 

[krypto]

There are many, many videos on Youtube demonstrating the single point threading technique and how to grind the tools. Since this is LH threading, you will be moving the saddle away from the chuck which should be easier.

 

[djc]

I am guessing 1/4-24 which does exist.

It is funny how close the 1.0mm is to 24 tpi.

This claims to be 1/4-24 left hand:

https://www.amazon.co.uk/Burkit-Round-Threading-Machine-Thread/dp/B0B5DJW7QZ

1mm pitch is exactly 25.4 tpi. This metric stuff is not alien technology. Or if it is, they landed long ago on the other side of the Atlantic and Pacific to you and are rapidly approaching from both sides...

 

[Richard Hed]

for such things as this, try Shars, of course, but also try:

https://www.victornet.com/departments/Hand-Tools/60.html

I have bot many tools from Victor and am quite satisfied withthe quality. It is an excellent place to get LH tools. I have bot many LH taps from them. Never bot LH dies however, becausse I can single point the part on the OD

 

[sarel]

The thread is 1/4" - 24 tpi lefthand

 

[pbilling13]

I have a Greenfield GTD Tap Handle No. 5 (also includes "5B"). It is currently missing the moving jaw. It has a reverse thread that threads into the handle.
Curious if anybody has one of these and can pull the moving jaw out and share the Thread pitch and Thread Diameter?
The fixed jaw comes out after releasing the set screw and then the moving jaw has enough travel to screw out of the handle.
I have been able to get a Drill Chuck retaining screw to thread in but it seems too loose. It is 6mm-1.1 pitch Left Hand Thread. This is close to 1/4-23.
Mr. Pete published the specs for the No 6 or 7 on a video and it was not a standard thread.

Hopefully someone on here has one and will help me out.

Thanks,
Russ

Greenfield GTD Tap Handle No. 5 5B Thread pitch and Diameter of Jaw

Found this on Amazon,
https://www.amazon.com/Aceteel-Roun...8&sprefix=1/4-24+left+hand+die,aps,165&sr=8-1