Can anyone one id what this is or what it's off of?
It looks like it might be a lathe chuck but I never seen a two
jaw lathe chuck. Maybe just a vise? It has Dovetails in the jaws.
(https://forestryforum.com/gallery/albums/userpics/39553/Vise_1.JPG?easyrotate_cache=1508631590)
(https://forestryforum.com/gallery/albums/userpics/39553/Vise_2.JPG?easyrotate_cache=1508631632)
(https://forestryforum.com/gallery/albums/userpics/39553/Vise_3.JPG?easyrotate_cache=1508631676)
I think its just a self centering vise. The dovetails hold the actual vise jaws which would be hard steel. Just my guess as I've never seen one exactly the same as yours.
I have a smaller two-jaw lathe chuck with similar dovetails. You can make specific slide in jaws to hold a particular (and short) piece of work, and it's very quick to clamp and release the work for production.
Probably in common use prior to the advent of collets.
I bought the vise to make twisted bars like this. The vise will be on the tailstock side of a home made
metal lathe and a large 4 jaw chuck will be on the headstock side powered by a large slow turning
gearbox motor.
(https://forestryforum.com/gallery/albums/userpics/39553/Twisted_steel_railing.JPG?easyrotate_cache=1508669557)
something like this but much bigger and heavier.
(https://forestryforum.com/gallery/albums/userpics/39553/twister.JPG?easyrotate_cache=1508669997)
Twisting bar stock is a common blacksmithing procedure but unless the steel or iron is properly heated I'm not sure it could be repeated with any uniformity. While a common procedure it is also an art to get it uniform.
Good luck!
It would much easier to get a uniform twist whilst the metal is cold. The trick to even twists is absolutely uniform heat or in this case lack thereof.
The picture I posted is from Dominican Republic. I was watching them twist
the iron cold by hand. They had no help from any power type tools. I know what
I build will have the power to twist it cold and the way I'm going to build the
machine will keep it pulled taunt so I'm hoping it works. I'm open for ideas.
I've twisted a lot of barstock and always did it hot and it came our very well. For short stuff I throw it in the forge and work it in the vise. But for long stuff we have a setup kind of like you talked about, a vise on 1 side and a slow turning motor on the other, but we have a forge that is open on both sides on a track. So we heat it up and roll the forge down as we roll it with the motor. It works well for long stuff such as handrails and they come out very uniform, just takes patience. And if you ever do something made of more than one piece, say 4 pieces of 3/8" cold roll turned together then you would have to do it hot.
I got a forge but I was hoping I did not have to use it...
I guess it depends what kind of setup you have. I've never tried to twist it cold, it's pretty darn easy hot though. And I've twisted 1" stock before pretty easily out of the forge.
Looks like it can be done cold...
https://www.youtube.com/watch?v=ForKWthpxz8
That machine has some serious power
My Dad worked for the power company. He was on a job wrecking an old transmission line. Every night he brought home cross arm braces. They were flat steel about 1 1/4" X 5/16" and 3' long. His intention was to weld a fence to enclose our backyard. I got the job of twisting the braces into a spiral just like that machine. He had a vise rigged up to hold one end and a pipe for the brace to fit into so it would remain straight.
He gave me a big bar to do the twisting and I was to do so many every night after school. He would weld them into the top and bottom rails of the fence when he got off work. It was cruel and unusual child labor....at least that's what I thought at the time. :D
Quote from: Kbeitz on October 22, 2017, 08:28:21 PM
Looks like it can be done cold...
https://www.youtube.com/watch?v=ForKWthpxz8
Oh it defiantly can be done with the right equipmeant. I'd love to know what size motor and gearing are in that machine. If I could afford one I'd defiantly have it, but for now, I'll just get it hot. Lol
There was a shop in town that made one with a slow turning gear and what looked like a model A transmission it could turn all sorts of stuff,this was there bread and butter.
I helped my grandfather twist hundreds of feet of it COLD with a pipe threader we rigged up and a vice on the other end to keep it streight. Perfect spiral every time.