Chris In Milwaukee
Ain’t no mo’
A friend loaned me a die so I can thread the end of a tube to use as an axle. It seems it’s not as easy as it should be. Maybe I ought to hire this one out. 
Making threads on tubing
- Thread starter Chris In Milwaukee
- Start date
Chris In Milwaukee
Ain’t no mo’
Honestly no idea. He handed me the die for the tube I asked him for. I didn’t ask much more. He’s a hydraulics machinist kinda guy, so presumed he knew what I needed. But I reckon one can’t assume. Looks like it was hungry for a lot more material than I expected.
It's pipe so it will be NPT or UNF. NPT is by far the most popular. NPT has a taper. Just like that photo above.
Chris In Milwaukee
Ain’t no mo’
I couldn’t see any markings on it that indicated the size. It just said “start other side”.
Chris In Milwaukee
Ain’t no mo’
Since this is a “vehicle” axle, I presume it’s a flat thread. But the carnage above sure looks tapered, doesn’t it?
Chris In Milwaukee
Ain’t no mo’
The blueprints for this axle say ‘3/4”x.065” fine thread’ which seems a little obscure. So I asked for that die and here we are. 
The blueprints for this axle say ‘3/4”x.065” fine thread’ which seems a little obscure. So I asked for that die and here we are.
That's a standard 3/4 OD pipe with a .065 wall thickness. NPT is not fine thread and has 14 TPI in 3/4. Time to make a phone call to the company and ask them what standard the threads are.
kasnerd
Danny's Red Headed Step Child
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- Aug 15, 2019
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You should be able to take that die to any plumbing shop and get it threaded properly in the machine. Doing this by hand is a fool's errand because the force required when nearly done (because of the taper) will cause wobble and eat all the threads you just cut.
Chris In Milwaukee
Ain’t no mo’
Fine idea
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- Jun 10, 2019
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Bump