tig welding

[skip99]

I have used a lincoln weld pak mig for the past 20 years, it takes a little work, but is fine.
I have been told that a tig will produce a softer weld, less heat, and easier to work, I am about to chop a top on a 51 truck.
I would just like some input as to whether it is worth it..
I saw a neat little miller at the Good GUys show.

[CoolasIce]

i don't know about "softer" weld, but you can control the heat better with practice.
You'll need to practice a lot before trying to weld sheet metal. i would use the mig for the chop job.

[Hot Rod Mike]

I have used a lincoln weld pak mig for the past 20 years, it takes a little work, but is fine.
I have been told that a tig will produce a softer weld, less heat, and easier to work, I am about to chop a top on a 51 truck.
I would just like some input as to whether it is worth it..
I saw a neat little miller at the Good GUys show.

I would agree w/CoolasIce. Stay w/the MIG until you have time to try the TIG & practice on a lot of scrap pieces before trying to chop a top. I just completed chopping the top on my 33 Ford, filled the roof, bobbed the rear fendors, welded in new quarters & re-skinned one door using a MIG. I am no pro by any means, but I worked diligently w/hammer & dolly to achieve a level where no bondo will be required (hopefully 8). You can hammer & dolly MIG welds :0

I'll try to post some photos later.

Good Luck,
Mike

[slyhog22056]

Although TIG welding does produce a softer and better weld you must have a very close fit and have extremely clean sheetmetal,
MIG welds are harder than the surrounding material, very forgiving with sheetmetal cleanliness and not so close fits, however if you put a MIG weld on a large flat area no matter how good you hammer and dolly it or fill it the weld with plastic or "lead" it will be visable on dark colors. If you paint a section with black paint and prep it according to the way it is supposed to be done and set it out in the sun and let it heat up the sheetmetal will expand more than the weld and become visable. so dont mig weld a large flat area hide your welds along seams or natural crown areas. Back when i was younger a lot of top chops were done with a torch and steel wire, the expansion rates were pretty close and you couldnt tell where the welds are heated up or cold.

[CoolasIce]

Explain how the weld is "softer".

[slyhog22056]

Hardness and softness is determined by wire softness and amount of heat from welding current involved. TIG wire is extremely soft compared to an MIG wire and takes less current and heat to use