Welding Methods for Chassis

[Trif]

I cut and welded my chassis using a a metal cutting bandsaw and mig. I'd never used a mig before, but having talked to welder friends I was convinced that it wasn't too difficult to learn. I bought a 150A fan cooled machine and sat down one weekend with a pile of 1" box off cuts and by the end I'd cracked it. The one thing I found that helped more than anything else was an auto darken visor, it was worth every penny. The metal cutting band saw was from a previous project and made the cutting of the parts a doddle. Accurate angles and lengths made the assembly and tacking fairly straightforward. The finish welding caused a few backtracks but the finished chassis came out to the mm thanks to the excellent cutting list in the book.

[acra]

Originally Posted by Trif

I cut and welded my chassis using a a metal cutting bandsaw and mig. I'd never used a mig before, but having talked to welder friends I was convinced that it wasn't too difficult to learn. I bought a 150A fan cooled machine and sat down one weekend with a pile of 1" box off cuts and by the end I'd cracked it. The one thing I found that helped more than anything else was an auto darken visor, it was worth every penny. The metal cutting band saw was from a previous project and made the cutting of the parts a doddle. Accurate angles and lengths made the assembly and tacking fairly straightforward. The finish welding caused a few backtracks but the finished chassis came out to the mm thanks to the excellent cutting list in the book.

I remember having a go with all the welding techniques in school - my favourite was TIG, I was pretty bad at the other two
But practice should help! And naturally I'm not gonna take on the task without being sure I'm good enough.

I used an autodarken mask, and a regular one (as well as one of them old style hand held ones (!)) and definitely loved the autodarken!

[Trif]

sounds like your starting from a better level than I was at, go for it, it's part of the fun!

[locostkiwi]

ive been a welder for the past 20 years
im welding my chassis 25x25 shs 1.6 thickness, using a 170 amp single phase mig, gas im running will be carbon dioxide, ( use plenty of anti splatter spray ).
For all my front and rear end suspension parts, ill use mig to tack them up but over here in New Zealand all final welding of suspension parts MUST be tig welded up then crack tested.
Also we arent allow to weld the steering shaft MUST be splined and pinched bolted to the universals.
hope this helps

[acra]

Originally Posted by locostkiwi

ive been a welder for the past 20 years
im welding my chassis 25x25 shs 1.6 thickness, using a 170 amp single phase mig, gas im running will be carbon dioxide, ( use plenty of anti splatter spray ).
For all my front and rear end suspension parts, ill use mig to tack them up but over here in New Zealand all final welding of suspension parts MUST be tig welded up then crack tested.
Also we arent allow to weld the steering shaft MUST be splined and pinched bolted to the universals.
hope this helps

That does help mate, it's interesting the regulations you have for welding, but a good idea I think. What level of crack testing do you have to conform to? I can do surface crack detection (dye-penetrant Non-destructive testing) but unless I get my hands on some of the fancy gadgets I can't do sub-surface myself, and we don't test for cracks to my knowledge.

Out of interest, would you reckon that Tig produces a better weld, if suspension has to be Tig?

[locostkiwi]

for non destructive testing i will get my A arms etc.. X-rayed,
cost is about NZD$40/item.
My personal opinon is that TIG welding does do a better weld than MIG, but i have seen people TIG weld and it looks like s**t, by the way I,m getting my arms etc.. TIG welded by a real pro at it. im not that good at TIG welding so will leave it to experts..