Welding Chain Links

Of course I could MIG, TIG, Stick, FCAW, or even O/A weld them, but this looked electrical and autogenous.

I might be be able to autogenous TIG, but it be a thin spot. This looked like they pushed the ends together.

I've seen the videos of production of chain and it's electric resistance butt welded from what I've seen.

What diameter wire or rod are you talking about if you TIG weld it. I've butt welded quite a few items in the 3mm to 5mm region with TIG, not had to try larger or smaller, and found the surface tension holds the molten metal in place and forms a nice joint sometimes with a small filler addition.

Its pretty easy to make a short very light duty chain with an appropriate bender. I have a few. Purchased and shop made. Its adequate for decorative work, or even something like a light fixture, but I'd like to be able to weld the links. I've seen a process (don't recall where) that looks like they get the ends hot and stick them together, but the logistics don't make sense to me. Electricity don't flow the right way for that to happen in my mind. Bob La Londe CNC Molds N Stuff

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I mostly use chain for fairly short logging slings and buy everything that will be heavily loaded in tension. Dealers in logging and rigging equipment have a much better and wider selection of chain sizes and strengths and connecting fittings than hardware stores. Sellers Crane Service in Yuma may know a local source.

Grades up through 70 may be carbon steel which can snap without warning when overloaded, the higher grades rated for overhead lifting are alloy steel that deforms and stretches first.

A county fair blacksmith showed me how to forge weld traditional chain for ox pulls, quite quickly. The 3/8" rod is bent hot into a U on a simple jig, cut or sheared from the rod and then the ends tapered to up and down wedge shapes with convex contact surfaces from a skilled hammer twist, and bent inward to a V, overlapping and nearly touching.

When fluxed with borax and heated white hot the ends are hammered together to join the link and quickly rounded on the anvil horn. As the convex surfaces are forced together they hopefully squeeze the flux out as the weld contact area expands without trapping any.

Since he was making only one link there was a delay while reheating, several could be waiting in the fire to speed the process.

The jig which fit onto the anvil face was a flat with the U in the middle and one raised side to restrain the end while hot bending the rod around the U.

He had customized tongs for the task. I think standard farrier (horse shoeing) tongs with two spoon-shaped jaws spaced apart by the thickness of the blank would do. The spoon edges give width to firmly grasp curved shapes held at angles like horse shoes, or chain links.

I made long sidewall links for custom snow/mud chains for my tractor by overlapping and welding the joints. T'weren't purty but the mud didn't mind.

Way down on my to-do list is a set of grooved spotwelding tips to weld chainmail links.

I've seen the videos of production of chain and it's electric resistance butt welded from what I've seen.

What diameter wire or rod are you talking about if you TIG weld it. I've butt welded quite a few items in the 3mm to 5mm region with TIG, not had to try larger or smaller, and found the surface tension holds the molten metal in place and forms a nice joint sometimes with a small filler addition.

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A half round groove in a firebrick, cut with an angle grinder or chop saw, might help hold the link in place and confine the puddle. Metal spacers could support the one or two links that join it.

If I play with this I'd probably want to come up with something really fast. This is not for any kind of load chain. Maybe not even a decorative load like a lamp. Its just one of those things I want to play with, like a 3D printer.

For loads I have 4 3/8 load chains and chain binders. I put each load chain in an ammo can for easy hauling. Two will fit, but its a little heavy with two. I also have a bunch of those 3700/10000 ratchet straps. The last several vehicles I've hauled I used ratchet straps, but I like chains when I haul my tractor. I always used chains on my scissors lifts too, but I sold those when I quit contracting.

No, this is just playing.

The last weld of this type I did on 3.2mm CCMS and the guy I did it for made the jigs in plywood, I just asked that he relieved it locally next to and behind where the joint was so any wood burning wouldn't affect the weld. IIRC it had about 6mm either side of the join and 4mm behind and there was hardly any charring of the wood as it was argon shielded as well while the weld pool was at its hottest and during post flow as the weld was cooling, the weld only taking a couple of seconds plus the post flow time. With this type of butt weld I've never found any need to support the weld pool as the surface tension of the molten pool seems to produce a nice cylindrical joint if no filler added or barrel shaped if filler added. I guess if you added loads of filler it might drop but that's not needed.

For loads I have 4 3/8 load chains and chain binders. I put each load chain in an ammo can for easy hauling. Two will fit, but its a little heavy with two. I also have a bunch of those 3700/10000 ratchet straps. The last several vehicles I've hauled I used ratchet straps, but I like chains when I haul my tractor. I always used chains on my scissors lifts too, but I sold those when I quit contracting.

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That's a good idea, I have 3/8" Gr70 and 5/16" Gr43 transport chains that need storage and carrying containers.

Usually I take a lever chain hoist and some chain in a horse stall bucket because the hoist will also pull a load up a ramp. The ladder rack I made for my truck is strong enough to pull 700 Lbs (tested) into the bed due to diagonal side braces to the rear stake pocket eyes. At that load my wooden stake pocket fillers (or the sheet metal pockets) began to shift. The hoist is a 2000 Lb one from Northern with 12' of chain, the bucket keeps the loose chain end out of the dirt.

The 91 Ranger is rated for and OK with 1000 Lbs within the bed but 700 at the end of the tailgate bottoms it to the overload bumpers, which I've broken off while logging and had to replace.

Yesterday it passed a careful state inspection with NO areas of concern noted. They know I can and will fix anything suspicious.

I reached 1000 Lbs of pull with a 2" D handle ratchet cargo strap. It falls off quickly as the strap winds larger on the shaft.

When stuck in mud I cut sticks to line up like tank treads, but need something for the short pull onto them.

Commercial chain making uses kick-butt resistance welders (like spot welders).

Each side of the open link gets clamped down and then oodles of current are applied at low voltage. The ends glow red and when they melt the clamped ends slightly nudge together. Current is shut off and they're left to cool. The bulge or collar formed is knocked or ground off. Lots of youtube vids show the process:

I think oxy-acy or tig with little to no filler would be the way to go. I made a few with MIG but the added filler necessary for welding is a pain to grind off afterwards...

I think you are referring to a "forged" chain. the ends are pushed together in a semi-molten state - basically forge welded.

Does anybody know if the welding is done with AC or DC? I'd think AC, since the loop side of the link presents a reactance that could be tuned to favor sending more current through the joint. But, it isn't obvious the effect is big enough to be useful at frequenccies consistent with delivering enough power.

Thanks for posting,

bob prohaska

Does anybody know if the welding is done with AC or DC? I'd think AC, since the loop side of the link presents a reactance that could be tuned to favor sending more current through the joint. But, it isn't obvious the effect is big enough to be useful at frequenccies consistent with delivering enough power.

Thanks for posting,

bob prohaska

------------------------------ If the current passes through both ends crosswise in parallel to heat both independently there would be little current around the loop.

Is that in fact the current direction? Most spot welding tries to guide current through the weld, AFAIK. Welders for single-sided welding of battery pack connections don't, but they work on much thinner material.

Thanks for writing,

bob prohaska

Is that in fact the current direction? Most spot welding tries to guide current through the weld, AFAIK. Welders for single-sided welding of battery pack connections don't, but they work on much thinner material.

Thanks for writing,

bob prohaska

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Battery lead spot welders including mine pass current between two closely spaced contact probes, not the battery internals.