Mig welding stainless steel. A few questions.

[tollermccallum]

Just after some advice regarding welding some stainless steel tube. I'm going to start building a kite buggy out of 304 grade stainless tube, i'm planning on doing the welding with a MIG but have nevr welded stainless before so am a little unsure of the wire i need to use and also any little tricks that could be helpful.

I work in engineering and have quite a bit of experience welding but it's always been mild steel, i'm planning on using the welding gear at work as i don't fancy tackling it with my little arc welder in the garage.

Any help appreciated.

Kris

[Andy Dingley]

Really don't.

Kite buggies are basically bikes. Now how many MIG-welded bike frames do you see ?

Go the easy route. Get a simple steel tubeset and silver solder it. You can tool up for this for peanuts. Brazing hearth, natural draught propane torch and some cadmium-flavoured silver solder cheap off eBay.

If you really want to be posh, then TIG weld it. This lets you use aluminium (not a good idea, IMHO, as much kite buggying is done on salty beaches), stainless steel or even titanium. Ti is dead easy to TIG weld - as easy as stainless and much easier than aluminium (IMHE, as the world's worst aluminium TIG welder). Heat treat and passivation are easier too. OK, so you need an aquarium, but that's hardly rocket science.

I'd rather gas weld a stainless buggy frame than MIG it (although I'm getting a little wary of fluorides in fluxes these days). MIG and stainless is fine when you want a big thick bead, you're doing big production welds in a hurry, or you're making water tanks. But for delicate work in frame tubes, it's just not the right process.

[Rob Morley]

You'd normally use socketed lugs when silver-soldering a bike frame. For lugless we always used to bronze-weld with oxy-acetylene.

I think titanium would be the preferred material in this application, but I'm no expert on kite buggies (not even an expert on bike frames any more - it's been too long).

[Andy Dingley]

You can go either way - lugged frames are certainly easier to make, especially for three-dimensional frames like trike or buggy designs that are otherwise hard to jig.

I'd avoid bronze welding - it only really has advantages on those tubesets with funny factory heat treatment. Apart from those, TIG is easier.

A much underrated material. Easy to work with and these days it's almost cheap (I use it for mithril-smithing).

[Rob Morley]

Eh?

[Mary Fisher]

LOL!

Think JRRT.

Mary

[Andy Dingley]

It's only "black" smithing if you're working "the black metal" (iron).

one on the left is titanium, the other two are steel.

[Mary Fisher]

What size are those penannulars? Is that from your own website?

Mary

[Andy Dingley]

Any size you like - They're mainly made to order. Huge great hulking things, if you're a LARPer with a habit of dressing as an armoured bear. These are about 2" diameter for the steel ones, a bit too small for the Ti one.

I doubt I'll bother making any more. The market value of them is only about a fiver, because it's folded with cold-worked ones (bent rod, with the ends squashed in a press). The differences are obvious when you look closely, but the buyers don't appreciate this.

[Andy Dingley]

"folded"? WTF is this speech rec. thinking of?

Try "because they're compared with cold-worked ones " instead.

[Mary Fisher]

Yes, it shows ...

As much as that??? Spouse doesn't charge anything like that!

Ours do, they're solid. The penannulars that is, before you jump to the obvious conclusion :-)

to get excited about a brazing hearth!

Mary

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[Andy Dingley]

It works very well with a pashmina! You don't even need to make a hole.

(Lovely Indian pashminas, £40 in most colours. Better yarn quality than any others I've seen under £100)

For hot smithed work ?

Fixed - thanks

[Mary Fisher]

But what about more closely woven fabrics?

Yes.

I'll have a look,

Mary

>

[Andy Dingley]

There are few things more closely woven than a good pashmina - these fit _through_ the ring, and it works as a clamp rather than as a pin.

[Mary Fisher]

Oh - you mean the pin doesn't pierce the fabric? The pashmina is threaded through the closed penannular?

Found the hearth stuff by the way, thanks. It's very similar to what Spouse wants to do with the rather larger night storage heater firebricks he's been collecting. He's still using a small kettle style of hearth he inherited but it has its limitations.Good job he doesn't want to make swords!

Mary

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[Andy Dingley]

You squish the fabric together, lay the two ends _over_ the pin, then close the ring.

I'll try and get the shop-elf to pose for a picture.

There's the cylinder from a 45kg BCF fire extinguisher (ex RAF) in the back of the car. When I get A Round Tuit, it's to have the ends made into doors and burner holes, lined with ceramic wool and turned into a broadsword-sized gas forge.

[Mary Fisher]

So it's threaded though!

I really think I know what you mean. But if the shop-elf likes posing go ahead!

Good idea. But we don't want to make edged or any other weapons, too many other folk doing it. Each to his own.

I shan't tell him about the fire extinguisher thingy, he'd find a use for it!

Mary

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[Tim Lamb]

In article , Mary Fisher writes

I acquired a stack of refractory blocks when the pottery kiln was changed at our local school. They work very well for getting large lumps up to red heat using a conventional oxy-acetylene torch.

regards

[Mary Fisher]

I could do with such a stack for the bread oven he's going to build for me. When Andy's finished with that round tuit.

Mary

[Tim Lamb]

In article , Mary Fisher writes

They are rather inclined to shed dust which might impact on your dentures:-)

regards