Die thread alignment 1/4-20 stock

[pcguy]

Did a search and came up empty on specifics, so here's my question:

Over the years when I needed to put some thread on some stock rod, I never faced a requirement that the shaft was going to rotate at high speed so I wasn't terribly concerned with the thread alignment.

I've seen some TAT's advertised for this purpose, but they seem overkill for Die thread alignment on 1/4 stock.

Has anyone developed a method of aligning a die on a piece of stock held in a vice?

All replies much appreciated,
Nick

 

[L Vanice]

There are die stocks with various means of centering built in. Most I have seen are not very good. A lathe could be used to make a dedicated 1/4 inch die holder with a long pilot hole concentric with the die bore.

Personally, I would single point thread the bar a little oversize and then take a light pass with a good die to get the thread to the desired final size. "Good die" is the key to getting a good thread. Hardware store carbon steel (Ace, etc.) dies do not cut it.

Larry

 

[Bobw]

Some parts I do on occasion (small qty) have 2.5" of 1/4-28.

I made a die holder that has a pilot diameter to keep the stock centered, and
I've also on occasion turned a sacrificial pilot diameter on the end of the stock
so the die starts centered...

Basically just something to hold the die, and a diameter to wrap around your stock so it all
stays centered.. Not a lot to it. A way to drive it wouldn't be the worst thing either.

Its pretty much a mickey mouse approach, but for the few parts here and there, its worked out for me.

 

[pcguy]

Many thanks for all the help. Thought it was important to reply with the method that I used to get this behind me. Turned out that the high rpms didn't contribute that much to the issue, It was the shaft that I was adding the threads to, which was a cheap commercial product and was causing the issue from the other end.

The shaft was originally only 2.5" long and I only needed it to be 1+". So, I put the shaft in the drill press and made a long taper with a file. That allowed me to start the die without much loss(or any)of alignment. When I had cut enough threads, I just cut the taper off. Simple eh? LOL

Thanks again,
Nick