MIG welding

[k8icu]

Anyone have any advice on mig welding on the 151 body? I'm doing some repairs on mine and I keep burning through the metal. I've got the welder down as low as it will go.

Thanks

[Spike]

What size wire are you using? Are you using flux core or a shielding gas?

I don't think I ever burned through with mine.

[Ralph Fuller]

Frequently asked questions about Mig welding at Eastwood.com:
http://www.eastwoodco.com/jump.jsp?item ... SubCat=857

[k8icu]

Flux core .30 wire....Which is the smallest the machine will take.

It's not a Linclon-Electric variety of machine...more like Harbor Frieght variety and I did get some spots that welded very nicely, but where the metal is thin from rusting it would just burn right through.

[Ralph Fuller]

I'm using .025 wire

[halftracknut]

back up your welds with a piece of brass...weld will not stick to it and the brass will help with burn thru...you may have a machine problem... I use mix gas 75-25 argon-Co2 with a flo rate of 25 and .023 0n thin metal...you might have to cut back to thicker metal on your body?.............HTN

[Spike]

I don't think much of flux core unless you're welding outdoors. I only use an arc welder for outdoor stuff like my dozer or tractor otherwise I take the part off and bring it indoors. I think shielding gas is the way to go. I'm no professional, but I did take a class at the CC years ago. When you have a ranch something always seems to need to be welded.

If you're welding rust you might as well be welding air, there's nothing there. The "trick" or rule to doing a quality weld is all in the preparation. The weld site needs to be shiny metal, doesn't matter how you achieve that...sand blast, wire wheel, grinder or hamburger pad. If the metal is already thin use a scotch brite-type pad for a grinder (hamburger pad.) After you clean it up, if you find it's just a small thin spot you can use the brass backing trick mentioned by HTN. I have smashed a piece of copper pipe flat to do the same thing (it also acts like a chill plate). If it's a larger cancerous area you really need to cut out all the cancer and replace it with a suitable piece of the same gauge metal.

I have done welding on old thin metal, like a housing cover, and was too lazy to change my whole set-up for one weld and just turn everything down low; move the wire back and forth between the seam and make a small puddle weld let it cool, then move down a little stitch weld-style do another... repeat... then if needed I will turn it up a notch (one power and feed-rate level) and go over the weld real fast to make it more uniform and monolithic.

If you practice welding, and have the right lenses that are clean, when you start welding you can tell by sight and sound if the settings are correct. It sounds like bacon cooking to me. You will have a puddle going, if you look at that puddle you will see what I call an eyeball, on that eyeball is a cornea. You are moving the cornea back and forth across the seam. Like anything it just takes practice.

Another mistake people make with mig welder is welding one-handed. I hold the gun in my right hand and use my index finger on the trigger. I hold the top of the tip about where it threads to the gun with my left hand, my left elbow is pointing up and my right arm is closer to my side. This provides the best control and is less fatiguing. All the right hand is doing is controlling the trigger the left hand is doing most of the motion.

A good set of clamps and magnets are a must.