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Keith Marshall
 
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Default type of gas and pressure setting for mig

Had an extra set of gauges and fittings and guessed around 12 lbs for
pressure.


The regulator should be adjusted for flow rate, not for pressure! The flow
should usually be about 20 CFH (cubic feet per hour) if you're in still air.
If there's a slight breeze you can up it to 25 or maybe even 30 but if the
breeze is that strong you can probably forget it.

Look at the gauge on the low pressure side of your regulator. If it reads
CFH or SCFH you're in business. If it reads actual pressure you have the
wrong type.

A friend told me he didn't think you used argon but a mix of CO2 and
something.


Pure argon should be OK for stainless and aluminum but depending on your
welder you probably won't have much luck with aluminum. There are aluminum
kits available for the brand name welders such as Lincoln and Miller and
even with the kits it isn't the best choice for aluminum. The kits usually
include a new teflon liner and a different feed roller that can grip the
aluminum better.

For normal mild steel you're better off with a mix of CO2 and argon, usually
25% CO2 and 75% argon, often referred to as C25.

I'm guessing that your cheap MIG won't be able to handle aluminum at all and
probably won't be so good for SS either. Even if it can handle it you
should practice quite a bit with mild steel first. If you can't get it to
do a good job with that you can forget either of the others. And based on
what I've seen of that type of welder you're probably going to be limited to
about 1/8" thick with gas, maybe 3/16" with fluxcore.

As for the mild steel, what welder are you using? What size wire? If we
knew that we could offer tips such as wire speed and power settings that
should help.

Best Regards,
Keith Marshall


"I'm not grown up enough to be so old!"


"monkeydave" m wrote in
message . com...

Now I'm really confused.
I bought a cheap mig, sold as "Combo Mig-with gas or without" .
Wasn't surprized to find it didn't come with a gas bottle but it does
have a place for one and a hose. It actually works well with flux core
wire (included) so I thought if I bought a bottle It might work as well
with gas.
Welding supply store sold me a small bottle filled with argon and said
thats what I needed.Also bought a spool of wire for stainless and one
for aluminum.
The manual shows diagram to reverse cable connections to change to
non-flux core wire but no specs for connections or guages/pressure
etc.
Had an extra set of guages and fittings and guessed around 12 lbs for
pressure.
Gas comes on and off with trigger and sounds about the same as I
remembered but it's been 10 years at least since I used a mig.
Tried to weld thin stainless but with all the wire speed, heat, and
pressure combinations I tried, couldn't make a weld I would trust (or
want anyone to see)
A friend told me he didn't think you used argon but a mix of CO2 and
something.
Anyone out there have this info ?


--
monkeydave