Add spool gun, but keep steel gun

[carwhisperer]

I saw a writeup about a guy who added a spool gun to his MIG machine but kept the original gun. He could run steel through the OE feed system or aluminum in the spool gun, just by flipping a switch. I'd like to do the same. I have a cheap Harbor Freight 230V welder (I'm on the Oregon Coast, USA) with Argon. Previously I had a nice Eastman MIG machine with a spool gun and a second machine for steel. I'd like to think I'm downsizing, thus only one machine to weld both.
Anyway, as I understand it, the biggest issue is finding a spool gun whose motor runs off the same voltage as the feed motor on the welder. I plan to measure the voltage here today. Other issues include adding a switch or switches to shut off gun 1 while running gun 2. A further issue is that my cheap machine does not have a gas solenoid on the machine. The gas is turned off and on in the gun (actually I don't know how it works, whether it is a mechanical valve operated by the gun trigger, or something else). I suppose I would need a spool gun whose method for valving the gas is the same as what I have now./
Has anyone else done this, added a spool gun to a machine while keeping the original equipment gun?

 

[hotponyshoes]

Yes, you can add a spool gun on.
Either use a switching contactor to send power to the spool gun or, disconnect the power running to the torch and feed it to a dinze socket on the front panel to plug the spool gun into. Then feed a bit of cable out of the front with a dinze plug to connect the original torch power into.

If you get a spool gun with the same motor voltage then just put a socket for the spool gun on the front panel and a switch to change over.
You could use the same switch to activate the contactor (rather than swapping plugs) but you might also need a separate psu for the contactor.
In theory, you could skip the plugs/contactor and just have both the mig torch and spool gun live at the same time.
Might not cause any problems if you made up some holders for them so the one you are not using won't short on anything.

Never tried it in a welder without a gas solonide though. I expect you have a manual valve in the mig torch. I've never seen a spool gun with a manual valve though.
You could just put a t piece on the incoming gas line with a tap for the spool gun or, better, split after the reg and fit 2 flow meters with a valve on the spool gun one.

Might be easier (save gas) to fit a solonide for gas.

Before getting too into it maybe do a search to see if anyone has welded aluminium with that welder and how they got on with it?

 

[carwhisperer]

Thank you so much. I think you're spot on with everything you wrote. I also think adding a gas solenoid is a good idea. The last time I had one of these welders, I blew a hole through the gas line that goes to the gun. Not good to have something under constant
pressure that's buried inside that gun sheath