Weld? Braze? Solder? Epoxy?

Factual Questions
1

I want to create a gizmo that will need some metalwork. Mostly I’d like to create a wire/steel rod core that’ll have stuff then mounted to it.

So - what I need is a way to connect a lot of wire (perhaps 10-12 guage) and steel rods (probably nothing much of 4-6 gauge) together - preferrable cheaply. Picture a wire/kenetic sculpture as a base idea.

What’s the best way - assuming that my experience with joining metal is limited to soldering copper plumbing & soldering electrical joints?

2

I don’t think soldering will do all that much for you. What kind of wire are you working with (aircraft cable, single strand, etc)? If you get me more information, I can go ask the metal workers in the shop.

3

Whoops… Here’s the rest of my post.

Also, you may want to think about just drilling holes in your steel rods and passing the wire through. Might be easier than trying to deal with solder/welding.

4

Holes won’t work - The steel rods are just for a stong core, the real shape is going to be a mesh of bent rods.

I’m really early in this project, ie: just thinking about it, but my mental picture is single-strand wire - about what you you’d get if you straightened out a bunch of coat-hangers (although I’m not planning on using coat hangers).

Another way to think of this is “what if I wanted to make my own wire forms like the wreath forms, etc. that you buy in the hobby stores?”

5

You don’t say anything about how strong it has to be or what kind of stress it will be under. That makes it hard to say what’s best.

I’ve always been disappointed when trying to epoxy metals together. The epoxy usually gets brittle and things fall apart.

Solder will work if you don’t need very high strength. But…you will need a heavy duty soldering iron or a torch.

Brazing might be your best choice. For wire, I bet you can get away with using one of those tiny (and very cool) butane torches (e.g. http://www.xkms.org/JC-Whitney-13/Mini-Butane-Torches.htm). Fairly cheap and easily refillable.

6

It’s not going to be under much stress. It needs to be able to support it’s own weight, be rigid, & take the stress of transport.

Sounds like some experimenting with brazing rods is in order.

This started as a mental project for a front yard christmas light sculpture then morphed when I sort of mentally combined this kinetic sculpture I saw once at a children’s museum and finally added an advertisement for the K’Nex roller coaster.

Mental masturbation, basically.

7

“its” own weight, that is.

(a quick post before the apostrophe nazi’s get me)

8

“its” own weight, that is.

(a quick post before the apostrophe nazis get me)

9

ack

Didn’t hit the “stop” button fast enough…

10

For your application, which does not require the rigidity, electrical conductivity or any other property of a unitized metal construction, epoxy (especially putties) will be more than adequate, and offers far faster time to initial product. I’m quite accustomed to welding, brazing, soldering, etc. , so I might choose to do them instead, due to the immediate set-time, but there would be no other real advantage, so I might as easily choose epoxy. For a crib mobile, I might choose a metal join, because new parents are often wary of chemical exposure from babies sucking on less than perfectly cured epoxy (assuming they notice)

11

Actually, this is an easy one. If you already have a little experience soldering.

Buy yourself ten or fifteen feet of 12-ga Romex house wiring cable, and strip the insulation with an xActo. This will give you three long pieces of 12-ga soft copper solid wire, that’s flexible enough to be bent and twisted by hand, but is still plenty strong to support it’s own weight. It’s also dirt-cheap, at about a buck a foot or less.

Then just get a decent propane torch that can give you a fine, sharp flame, get some lo-temp (200 degree or so) solder and a bit of brush or liquid flux.

Soldering is absurdly easy, and copper-to-copper makes a bond nearly as strong as the base metal itself, even with a soft lo-temp solder.

Once the assembly starts getting complex, you’ll have to be more and more careful about the heating, so putting a join here doesn’t soften the solder over there, but that’s easy if you pay attention.

12

What about binding the pieces in place with a lighter gauge of wire? I’ve had some decent luck in art projects using fairly fine copper wire (I couldn’t tell you the gauge, but it’s about as thick as horsehair) and wrapping that around and around, tying off the ends, and then using epoxy putty to smooth over everything.

(I am VERY fond of twin-agent epoxy putty, the kind that comes in blue and yellow strips; you knead it together until it turns green, and then you have about fifteen minutes to work it until it hardens. LOVELY stuff!)

Trinopus

13
      • Welding is by far the quickest, easiest and among the strongest methods, but the equipment to do it is relatively expensive. If you want to do clean butt-joins however, it is the only way. It also allows the nearest joins–you can make a second weld less than a half-inch from a previous weld without much danger of re-melting the first weld. --And I am speaking of gas welding, oxy-acetylene. There are cheap <$100 wire welders now, one model is ~$80 but my experiences with cheap wire welders has not been satisfactory and the good ones cost $400-$500+. A mini gas torch will run $400 or so to get rolling but they are great for general shop and craft uses. You can for example heat up metal red-hot and bend and form it with pliers that you could not bend cold.
  • I would bet that solder would come loose–it is very susceptible to cracking when flexed. Brazing would hold a lot better than solder, but the most economical way to braze is to use a regular welding torch, because the tiny bottles of butane are relatively expensive fuel-wise–but with a regular torch, you could just weld it all anyway. And the store-bought metal ones that I have seen are welded also–if there was a cheaper way to do it well they would have done it that way.
    ~