Mig or tig, Which would you choose? Options

[r_towle]

Lots of sheet metal body welding, flares, patching, several cars.
I did use a mig for years, upgraded to gas mig.
My son took it.

So, I’m getting another welder.
I still have a gasless mig, and a scratch start tig
Neither are very good.

So, which would you choose? Why?
Willing to take the time and learn.

Rich

[Superhawk996]

@nathanxnathan

Try this TIG technique on dual layer panels:

It’s often the air trapped between the panels rapidly expanding that spits out of the weld puddle causing the electrode contamination - not the corrosion contamination between the panels.

Try pre heating the zone around the weld with the torch and light current before attacking. This heats the air between the panels and gives it time to expand. Then go in hot quickly to establish a puddle, then feed filler quickly and heavily. Sometimes I would need to downsize filler rod to avoid having too much filler going into the puddle at one time and sucking the heat out of the puddle or resulting in too much weld build up.

It sort of mimics the MIG process. Not fool proof but it usually worked for me. TIG welded all of my 914 chassis sheet metal replacement. Sometimes up to 3 layers.

[nathanxnathan]

@nathanxnathan

Try this TIG technique on dual layer panels:

It’s often the air trapped between the panels rapidly expanding that spits out of the weld puddle causing the electrode contamination - not the corrosion contamination between the panels.

Try pre heating the zone around the weld with the torch and light current before attacking. This heats the air between the panels and gives it time to expand. Then go in hot quickly to establish a puddle, then feed filler quickly and heavily. Sometimes I would need to downsize filler rod to avoid having too much filler going into the puddle at one time and sucking the heat out of the puddle or resulting in too much weld build up.

It sort of mimics the MIG process. Not fool proof but it usually worked for me. TIG welded all of my 914 chassis sheet metal replacement. Sometimes up to 3 layers.

@Superhawk996

I will give it another try when I work on the other side this weekend. I do preheat quite a bit with just a little bit of pedal. I tried to fill the lower hole that goes through both layers. I drilled it slightly larger to get the rust from the edges, and backed it with copper. The layers are tight there, very little space between. I then heat the center of the copper for about 8–10 seconds as the fill rod will go toward the heat. I have found that if you can get the smallest bit of weld to stick to the piece and then weld to that... it's like there's a threshold of dirtiness that you can't go past or it all flairs up. I've managed it in the past, but just as often I need 1 more second to finish the weld and bam, it all blows up and there's a huge blob of weld stuck to your electrode. I went through a whole electrode just grinding off blobs trying to fill 2 holes there before I brought out the mig.