Seems like a lot of work to me. You would have to switch both power and gas, unless you are going to run 2 different gasses. Then you need to control each individually.

With some outside-the-box thinking I'm sure you could figure a way to do it, but if there isn't a "kit" available from a manufacturer in that the set up for dual guns isn't already figured out and supported you're blazing your own trail.

Keep in mind, your settings for both are going to be different anyway. All you are saving is the swapping of the parts. Are you changing over between materials that often/quick to justify the work to do what you are asking? Seems like a lot of work to me, but if this is a hobby for you so be it.

 

The higher end Miller machines, like the MM 252, 255, 355, etc., have this as a feature. You can leave the spool gun and the regular MIG gun connected (they have different connections so nothing to swap) and which ever trigger you squeeze, the machine reverts to the last settings for that gun. When I has a 252, I would leave hard wire in the machine, and aluminum in the spool gun. The spool gun connected directly to the regulator on the argon bottle, so need to even change gas regulators if you had a dual bottle cart and two regulators. Pull the trigger on the regular MIG whip, and the brains of the unit would pull up the last parameters I used for steel. Pull the trigger on the spool gun and it would automatically pull up the last parameters I had for aluminum. Easy peasy.

I don't know if other brands can or cannot do this, but I know I have personal experience with it on the MM252 and 255

 

Almost all the mig machines made in the last few years seem to be spool gun ready. If yours isn't, its not that big of a modification to add one. Usually there is only 4 wires involved, two for trigger closure, and (+), (-) DC voltage for the feed motor. What machine do you plan to modify ?

HTH

 

I'm planning to add the feature to my Eastwood 175.

 

It's fairly simple to add a spool gun to a non spool gun machine in the back end is correct ie: Miller style or Tweco style. *Much more difficult with euro connect*. Most new spool guns are 24v motors same as the drive motor. Requires 4 pins and a 2 pole toggle switch. I've done it many times. You just splice the switch in between the drive motor board and the motor. Flip the switch to activate the other 2 pins for the spool gun drive motor. I have a crude but readable drawing if you want a copy.
( most machines have a 4 pin socket with only 2 pins in it for the trigger wires but as long as you have 2 for the trigger and 2 for the motors you're golden )

 

Thanks for the info, Rondo. I think I have it figured out, but am interested in your schematic, if you will, kindly, post it.

 

Picked up a spool gun with my last Hobart, have not tried it. Think I will, Richard needs some stuff done on his aluminum trailer at the tailgate. Just need a bottle of argon and some wire.

 

https://youtu.be/nSKGXHCv0y8?si=fI5RnAebchG8zQgx

 

This is my method of adding a secondary attachment for hooking up a spool gun to my Eastwood Mig 175. I had repaired the original wire drive connector with a 3D printed gas supply ring, which accepts the gun hose plug, so put it to use. I had ordered a replacement drive housing from Eastwood, and made a functional strain relief plug to hold the hose end.

The machine cabinet was lacking sufficient room to add the drive housing, so I attached it to the side support rail of the cart. Rather than employ a second gas solenoid for the Argon gas, I chose to use a diverter valve, downstream from the original solenoid in the machine, which tucked, neatly, inside. Now, it is a simple matter to change from one gun to the other by interchanging the small gun trigger plug, flipping the diverter valve, and switching from the machine drive to spool gun drive. I have my C25 and Argon gas bottles plumbed to my machines with a variety of T connections, so it is easy to change gases.

 

The rest of the photos...

 

One thing you might want to check is how the speed of your MIG gun motor is regulated. There are two common ways to regulate the speed of DC motors: pulse width modulation and variable voltage. The difference is that for variable voltage motors, the motor torque drops as the voltage drops. For PWM, the torque remains constant with speed. If you use a motor designed for PWM with variable voltage, you could have problems with the drive stalling. I think that most newer machines use PWM, but possibly not on low price units. Worth checking since when you read reviews on spool guns, it seems that some people have trouble with the drive stalling.

 

Not to worry, Bradley. Since I wired the connector for the spool gun in parallel (electrically) with the original wiring for the gun, the supplied voltage is unaltered. I just ran a jumper wire from the connector terminal to the newly installed hose connector, so everything operates as expected. Voltage and wire speed is still managed by the pots on the front of the machine. Thanks for your comment... we're all here to learn and, hopefully, pass along useful information.

Spool gun use for aluminum is, fairly, new to me, and I'm lovin' it.

 

You are missing the point. Just connecting the new motor to your existing wire is not a sure fire solution to the potential problem. If your original wiring varies the voltage and you try to use that to drive a motor that uses PWM, you may run into a torque problem on the new motor. Since yours happened to work, there was no mismatch problem.

 

The spool gun was sold with the Mig 175, so I assumed that Eastwood would supply compatible units. Apparently, I was correct.