chain

[Dorian]

I have a little item in the works that would benefit from linking a machined (or plasma or turret punched) part to chain. But how to mass produce something like that? How is chain manufactured, anyway? I'm particularly interested in using everything stainless. (Yes, those links at the big boxes with the threaded nuts would work, but cost too much in the long run) At this point, just knowing how chain is made these days (without hammer and tong, thank you) would scratch an itch.

[tattoomike68]

do you mean roller chain or link chain?

I do not know what you are doing but if you want to know what chain can do, go to a saw mill,it would blow some guys away to see the high speed machines run.(miles of chains)

[SGW]

Quite a few years ago I was visting my cousin in Portland, Maine, and one time when we were driving around he pulled into an industrial parking lot, which turned out to be that of a chain manufacturer. There was a small window in the side of the building where you could look in and see a machine automatically heating, forming, and welding chain links together. Except for that pretty vague memory I can't give any detail, except that it seemed to be done pretty much without human intervention.

[Dorian]

Yes, I meant regular link chain. I'm interested in making a unique pattern. I want to insert a machined pattern into links that would go off in three directions. I got a feeling this is one of those easy to concept/hard to build ideas.

[Ries]

Real commercial chain is welded at every link- they use a big induction welder to do this. Probably not very feasible for small runs.
Cheap window and lighting chain is just bent together, with a gap. This is easier to do, but not as strong. You can buy a variety of links for closing chain, besides the carabiner style you mentioned with the screw fitting. You can buy some with eyes on them, and a matching pin, that you squish shut.
But if you need stainless, you are going to be best off making your own connecting links, and then tig welding them. If you must have a per price piece of a few pennies for this, then you better be talking about hundreds of thousands, if not millions of parts a year. Then you could have a custom induction welder built- although stainless does complicate that a bit, it doesnt make it impossible. If you are only talking tens or hundreds of parts a month, then you will have to accept the cost of making them by hand with jigs- not that much really, once you get set up. I have done stainless, mild steel, aluminum, and bronze links like this ranging from 1/8" material up to 1" round bar- you bend the links using a hossfeld or di-acro style bender, easy to bend a hundred an hour or so. Then you squish em shut in place- low tech way is with two crescent wrenches. Then you tig weld em shut. A good tig weldor could do a hundred an hour if they were 1/4" round. So you either need to tool up, or find a fabricator that is set up to do this kind of small production runs. You could probably have the links premade, in any metal you want, by a wire slide house- a place that specialises in making wire for things like shopping carts and display shelving.
Its all very do-able.

[lunkenheimer]

Not exactly what you asked about but there are all sorts of stainless shackles, links, and stuff like that for boats (especially sailboats)

Not much is cheap, though, if it goes on a boat (except possibly beer)

West Marine is a good place to look(www.westmarine.com) (no affiliation) and there is a very limited selection at Lowe's or HD