pipe threader for twisting

jdm61

jdm61

itinerant metal pounder
Joined
Aug 12, 2005
Messages
47,357
I have seen a number of people using the large and rather expensive Rigid stand mounted pipe threaders for twisting damascus, I was wondering if one of the small portable handheld units would work for smaller bars? I just don't have the upper body strength to do it by hand.
 
we have a big one at work as well as a small portable one. first time i used it i thought Damascus twister. i know the smaller portable one threads everything we need. but i dont know how well it would twist Damascus. i would think it would work good as hot steel does not take much to twist.
 
Portable, machine should work fine.
I dunno about using it freehand vs. building a stand or other fixture.
Whatever chuck or gripping fixture you devise for it, I suggest painting a stripe or mark so its easy to count rotations.

They are beastly machines.
We have a Ridgid 300 what twists 5/8 sq. bar cold, hardly breaks a sweat. Its twisted hot 2" hex like butter.
 
Obviously, I would love to have a big Rigid suitably modified but even old, broke and rusty-crusty, those things are crazy expensive. the real ones are what? Over $4000 new? Rigid is proud of their product. Even their little handheld machine is well over $1000!
 
I'm amazed at how much torque those units have. Notice that it actually keeps spinning AFTER! I take my foot off the switch.
It doesn't even know there's a billet in there. No doubt it would twist quite large diameter steel while hot.
 
Nice video there, Karl! I looked for a used pipe threader at an affordable price for quite a while, they just don't pop up around here. People use them for their primary use and run them till they drop, then try to sell them for like $1K still... a Ridgid 300 is the best, and it would appear your machine is similar- with the quick chuck and the jaws right out front like that. Some other machines won't let you get in quite as close.
I saw a video on YT by Dionatam Franco, about power twisting, and noted that quite good results can be gotten by decreasing speed and increasing torque with a gearbox, driven by even a fairly small electric motor. You can use a separate motor and belt or chain drive a gearbox, or use a gearmotor outright. The body of the machine in general can be built very similar to a lathe.
So, I found a 1/2 hp gearmotor with (IIRC) 80:1 reduction from 1725 rpm, 3 phase so it's speed controllable with my VFD and fwd/reversible which is great for turkish twist and such, doing alternating twist directions. I set it up so the power runs last through a 3 phase foot switch (a largish knife switch put on the floor) so I can twist hands-free, and control things by being able to grab the billet while twisting or use water to slow twist in parts.
It works great, the largest bar it will hold is 1-1/8" square by about 28" long, and as Karl says the torque is amazing, even on that heavy bar the machine will "coast" a bit when you're done twisting and let off the switch.
You can see that the three jaw chuck is not good for either square stock or hot steel, so adaption is necessary if you use a threader. Karl's sockets are a good way, my machine uses a different type of holder- I'll post up some video here later today so you can see how that works, it's easier to describe by demonstration. I was able to put my twister together for basically no money other than welding rod and some grade 8 bolts, since I'm a scrounger... a good option if you can't find a threader.
 
Salem Straub said:
quite good results can be gotten by decreasing speed and increasing torque with a gearbox, driven by even a fairly small electric motor.
Click to expand...
That's the type I learned twisting on. My friend, Jerry Rados twists with an electric motor pullied to some kind of small car gear box off of something like an MG Midget or an Austin Healey. He even uses the gear shift to go from forward to reverse to change the direction of the twist!!
 
I'm not sure if it would work for you as it's still a manual approach, but I saw Jerry Fisk had a really slick twister, it held the billet on each end, and you simply turn a large crank to twist it. It looked to be a fair bit less strenuous than the regular vise and pipe wrench approach. He said it was uncle al/Riverside if I recall correctly
 
Geoff Flato said:
I'm not sure if it would work for you as it's still a manual approach, but I saw Jerry Fisk had a really slick twister, it held the billet on each end, and you simply turn a large crank to twist it. It looked to be a fair bit less strenuous than the regular vise and pipe wrench approach. He said it was uncle al/Riverside if I recall correctly
Click to expand...
Geoff, I have seen guys use those to great effect when making small bars for multi-bar damascus, but I ma not sure that it would help me that much for a 1 inch plus bar.
 
jdm61 said:
I ma not sure that it would help me that much for a 1 inch plus bar
Click to expand...
I use a similar hand crank on my Turkish bars. 1/2" at welding heat is about the max.
yCfMpm9.jpg



Those ended up like this:
Wdk1E1u.jpg
 
That makes sense. It could potentially be easy enough to make one with some built in mechanical advantage though. Something along the lines of a hand crank boat trailer winch. It obviously wouldn't be as fast and easy as a powered machine, but it could be a suitable middle ground
 
I bet one could take a large flywheel from a vehicle that used a clutch so you have some good mass. Use a couple flange bearings on a homemade stand and a high torque starter and it would have enough a$$ to twist hot metal. If one starter doesn't do it add a second one. The clutches built into the drive gears on the starter would ensure two motors wouldn't try to tare each other apart if one wanted to spin faster than the other. One if not two 12v car batteries wired in parallel. Leave them hooked to a trickle charger when not in use. Couple hundred bucks..
 
My research shows motor on a ridged 300 is only 1/2hp. Well that's what thy say it is, looks kinda small for 1/2hp. But that gives you an idea as to the power requirement for twisting. My plan is to Use this DC gear motor I have. It's .33 HP but man it's got some toque and it sits at around 60 rpm. It is rather large and quite heavy compared to other 1/2hp motors I have seen.

Photo%20Aug%2016%2C%202%2026%2033%20PM.jpg


Photo%20Aug%2016%2C%202%2026%2014%20PM.jpg


Photo%20Aug%2016%2C%202%2026%2023%20PM.jpg


Think it will work?
 
I just picked up a big, very old, Oester 302 threader for this purpose. Weighs about 1400lbs, huge handwheel operates centering vise and box wayed shuttle to move the vise in or out from the cutting head.

Got it dirt cheap, since it's pretty much scrap to most. Makes a Rigid 500 series look like a toy. Large frame, 2hp motor (size of a modern 10hp) with a large gear drive.

Think it was originally 4" or 6" capacity?

Anyway, Oester is still in business, and still has cutting heads and parts even though these were only made from the 20's to the 40's, they make seriously heavy duty (much bigger than this even), real industrial threading machines, but I've seen a few of them much cheaper than Rigids, just because they are less well known, and not portable contractor type machines.

This of course, is typical, larger, better machines, often command less money second hand than their hobby sized counterparts.

I'll try to post a photo, but check my IG if you're impatient.
 
Another potentially super inexpensive option I had been considering before I found this machine, are large drum brake lathes. Like the type that are used for turning tractor trailer drums. They sell for next to nothing whenever I've seen them, and they typically have super low speeds and high torque, plus potentially one end already good for holding billets. Most reasonably compact also.
 
You must log in or register to reply here.
Back
Top