Ok, been researching on how to weld with a MIG welder both on here and Youtube. It seems as though people do it differently. Some weld full seams, others spot weld and use seam filler on the joints.

What are the pros and cons of these two methods?

If I overlap the joints, can I seam fill between the pieces of metal and pop rivit in place, then later when dry and all set, go back and weld everything up?

Do I need to weld joints top and bottom or can use seam fill.

Learning as much as I can before I start.

Thanks

 

If you are talking about sheet metal for like your floors you should butt the ends up and tack your way along the entire joint.
On thicker plate it depends on the project whether you stitch or fully well the joint.

 

what are you welding? Sheet metal? Like...floor pans?

If you're going to weld it just weld it - tack in place, then stitch weld the seams, then go back and seal the sections that aren't welded. If it's lapped you don't need to weld both sides - just seal up the opposite side.

 

What is the advantage of butting vs overlapping

2nd question:

For patching in other sections of the bed, do I need to get 16 guage or can I go with a little lighter? 16 just seems hard to manipulate

Thanks

 

more material to weld to - easier to weld a lapped joint and not worry about it blowing through.

I'd use at least 20 gage

 

Yes, this is all flooring

 

you will need to spot weld along the unibody rails at a minimum

http://www.naxja.org/forum/showthread.php?t=906957

 

Also, researching seam filler, what I found is costing in the neighborhood of 25.00 a tube. Can any other sealant be used in it's place? I've heard silicone will eat the metal. More cost effective?

 

silicone is not a good seam sealer. You need something with better adhesion, and you can't paint over it.

 

Quick question: If I am welding, do I have to disconnect anything because of the electrical system?

I'm going to be passing electricity through the vehicle with the MIG welder. Does that electricity just go to the weld or can it transfer to some of the other electrical components and fry anything out?

Thanks

 

Some say to disconnect your battery but I've never had a problem

 

Yeah I'm reading a multitude of different articles where as they say to disconnect the battery power, disconnect the battery ground, disconnect both, bolt both leads to the frame, disconnect the ECM, disconnect all the ECM's, and after all that, you can still fry out the transistors in the alternator, plus any electronics which are relatively close to where you are welding. Yikes!

Then you read where others have been welding for four hundred and seventy five years and have never disconnected anything and never had a problem.........I love consistency......

 

If I'm welding real close to a control module, It makes me feel better if I unplug it, especially if using a higher output for thicker material.

 

I've welded the on the jeep, my duramax, and heavy equipment without ever disconnecting anything

 

Your lucky and Brave !

Ive seen too many MSD boxes smoked due to welding on race cars.
Id be thanking your lucky stars you have not fried the control module on that Dmax ,I dont weld on anything anymore unless the batteries are disconnected its the rules at work. I build hydraulic coil tubbing units we have the ecms removed before doing any welding on the engine skids.