Quote:
Originally Posted by Krylon32
When we were boxing deuce rails for about 10 years in my chassis fab shop we used a wire between S1 and S6 both for strength and ease of grinding. I can't find the exact number anymore. We used 75/25 gas. The man that worked for me for 10 years boxing rails got to be a dam good mig welder. When he first started he left a lot of material to grind but after a few years he was leaving minimal excess. We never had any complaints about rails separating so he must have burned them together good. Still seemed like we went thru a lot of 24 grit discs over the years
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I would bet this man you had welding took more time to make better fitting
joints. When welding with MIG you are always applying metal. On joints that
but up to each other depending on the thickness of the metal leave a slight
gap. .023 wire will make any welds required on autos. You can cut the speed
of the wire down real slow which cuts the amps or speed it way up and get
close to 200 amps. The voltage has to be adjusted to properly burn the wire
at the tip. You can speed smaller wire to get more heat or amps but you can
not cut large wire for real low heat. I got into MIG welding back in the late
40's when MIG welders were giant machines made by Arco and GE. They
were used on welding heavy metals. I made the first body shop machines
which we called Fender Menders. At that time C25 {75% argon /25% CO2}
was not available. We used a bottle of argon and a bottle of CO2 and mixed
them with a "Y" hose. The gas would build up pressure when you were not
welding and come out in a big gush when you pulled the trigger and disrupt
the arc for a few seconds at start. I put a small length of .035 contact tip in
the gas hose where it entered the handle of the gun. This cut the gas surge
and also let a little gas bleed out on the small ball of wire on the end of the
gun. This cooled the wire in gas making it easy to start the arc the next time.
My company made MIG welders for Air Products, Hobart, Forney and Snap On
tool company for years. I sold the company over 40 years ago and they still
make MIG welders for Snap On. In fact I think they are almost 100% Snap
On. For light MIG welding you need a lighter shaded glass than on larger
diameter wire heavy metal welding. I am close to 90 years old, my eye sight
is 20/20, hand is still steady and still do a little MIG and gas welding. Back
when we first started there was only a couple makes of small MIG wires made.
They were all hard and hard to grind but we got by. G.M.