Welding Tips and Tricks

Does anybody know if you can weld stainless with regular mild steel mig wire and strait co2? i don't have much to weld and don't want to invest in new gas and stainless wire.

Hey,

you can "weld" it but it wont be any sort of corrosion resistant weld. Also, the stainless steel will combine will the steel and cause a hardened area in the weld zone, that could be prone to cracking so dont load it with any weight. What is it you are going to weld?

Mick

I'm building a ratrod and i was going to use a keg for the fuel tank.

Goforth,

Can't you simply use straps and softeners to attach the keg?

I'm not sure I'd use e70- and CO2 to weld on a fuel tank with dissimilar metals.

Realistically, if it cracks, it will be at the weld interface, and not compromise the keg, but why do the same job more than once? Build a cradle for it, and strap it in, and be done with it?

Steve S

Goforthjp.

My guess is that you would not be doing that much welding, so consider stick welding it.
In that case you could buy those few rods of E309 (assuming the keg is the non magnetic austenitic stainless steel).

If the hotrod will be 'living' in a humid climate, you will notice in a short time the corrosion attacking the stainless steel. It will eat a hole in your stainless vessel.

Tanks.
Alexa

i'm going to strap it in but i have to weld fittings in it for the fuel lines and a filler neck so i don't think cracking will be an issue. I also thought about clear coating it to keep the welds from rusting. I appreciate the input guys.

Hey,

Mate, Id have to say, I would not weld that the way you are thinking. When I first replied, I assumed you were talking about a rack or a sculpture or something. As soon as you said fuel tank, red light... Fine idea you have, but for fuel, especially in a custom rod that may not be as predictable as a normal car, in terms of vibrations etc, the tank pipes could break without warning. A couple of bucks for a few stainless sticks or a love job from a buddy, and you wont have to worry,

Mick

Hi - allow for differences being opposite sides of the pond - but I'd check with your local MOT ( DMV ? ) place first - here a fuel tank is a tested part & must be type approved & crash tested - I've seen similar stuff to your intentions but I seriously doubt they are road legal - there's a fine line between a vehicle built legally but looks " edgy " & what I believe you would term a " Res ride " If you can use the keg then strapping it down on a cradle is the best way both for strength safety & looks.
If you can use the keg assuming it's similar in construction to a UK " beer barrel " then consider using the large center fitting as the filler - it should be thick enough to bore & thread so a standard pipe fitting could be used as a filler neck - at worst if you have to weld to any part of the keg - use this - it is the only thick part that is not under stress from the forming process - I doubt the rest is more than 18gauge & will deform badly if heated. to get fuel lines in / out then consider a visit to your local boat supply - they should stock various lengths of tank fittings - these are made to avoid welding on stainless boat tanks & are fitted via an oval drilled hole that the fitting is inserted through then turned 90 degrees & fixed with a gasket / plate & lock nut from the outside - this should avoid welding - if you have to weld then I think the best bet would be to make up a flat plate big enough to house all the fittings & filler then have someone Tig weld it on the top as a sort of saddle plate.
All the best with you project.

Brian,

You'd be stunned at the flexibility afforded the home-builder in the US. The perceived risk is to the builder, not the public.

If the vehicle is aready titled, modifications are generally not inspected, unless they affect steering, braking, or emissions, and not in all cases in all states. I've built my own fuel tank before, when the original rusted out. I was never questioned on it, and I was in a state that required annual safety inspections.

I'm currently in a state where safety inspections are required. However, I know my inspector mechanic, who knows I'm a FDOT semi-trailer inspector mechanic. He doesn't even look at my truck, just changes the sticker. He knows I maintain my truck, but you have to wonder how many "good ol' boys" pass their buddy's vehicle as a favor.

Steve S

Goforth,

Brian has a point.

Would it be possible to weld your bungs to a mild-steel plate that could be gasketed and bolted/screwed to the keg, to eliminate dissimilar-metal welds? At the very least, I'd use a pickup tube so the fuel outlet is at the top, so a cracked weld only results in a small vapor leak, rather than liquid from the bottom.

Steve S

Wow - I live in the wrong place - we have so many bullshit laws it's ridiculous & they think up more every week - especially for vehicles plus Police use vehicles as an easy target to make their books up with - their like a cross between sheriff Lyle Wallace from Convoy & the worst California highway patrol you ever met - the only people they don't hassle are illegal immigrants ( how messed up is that ) - it's scary how some of the 80's future sci fi type films have come to how it's gotten here. I wish I knew a vehicle tester that gave a little leaway - only thing they don't pull to pieces on annual inspection is my Chinese trike - they just don't seem to know what to make of it & so long as it has 3 tyres with tread their happy! My truck on the other hand is never so lucky. It's weird but I always assumed fuel tanks would be similar over there - I remember when GMC started the side mount tanks on pick ups & the issues in magazines about their safety.