It might cost less, the nice thing about the old welders is that they’re made with hefty transformers. I would imagine a tool and die maker might find a TIG welder even more useful.

the gas valve should be powered from a separate low voltage transformer and since the motor for the wire feed is usually powered from one, it should be available. Just tap it to power the solenoid, the post flow is a little more challenging but unnecessary to get this project moving.

I have resurrected many old machines to have them eventually replaced with new ones that are more efficient. I have 2 old MIGs that take up space and gather dust.

 

It might cost less, the nice thing about the old welders is that they’re made with hefty transformers. I would imagine a tool and die maker might find a TIG welder even more useful.

the gas valve should be powered from a separate low voltage transformer and since the motor for the wire feed is usually powered from one, it should be available. Just tap it to power the solenoid, the post flow is a little more challenging but unnecessary to get this project moving.

I have resurrected many old machines to have them eventually replaced with new ones that are more efficient. I have 2 old MIGs that take up space and gather dust.

I need a MIG welder perhaps once a year, so efficiency would not be a big deal in my case.
The gas valve control should be isolated from the mains, but the valve itself can be mains operated. Then a timer can start the wire feed after the gas has reached the tip. a gas saving trick is to have a low-pressure opening check valve in the inert gas line very close to the tip, so that the pure gas does not leak out between welds. It saves a bit of time as well because the delay does not need to wait for the whole line to fill.

 

What sort of material and thickness are you welding? My first machine tapped the transformer for 4 power settings similar to this and it was all but useless to get the voltage right. Anyhow I understand the challenge of getting an old machine working. Just tap it off the feed motor.

Make sure you’re DCEP if you’re running gas

 

a gas saving trick is to have a low-pressure opening check valve in the inert gas line very close to the tip, so that the pure gas does not leak out between welds. It saves a bit of time as well because the delay does not need to wait for the whole line to fill

That is a another tell that you don't know a thing about Mig welders. the first was -

If you can put the solenoid gas valve at the weld gun

The second is here -

So pushing the button on the gun would first start the gas flow, then switch on the power and start the wire feed.

 

The problem with a flux core welder is the price of the wire. Expensive and not available everywhere.

What world are you living in? If you know anything about Mig welding, you would know the flux core is real close in price to plain wire, and cheaper if you figure in the cost of buying both gas and the bottle it comes in.

 

I found a great source of my Argon do NOT go to Airgas, they are a rip off. I get fill about once a week when I’m busy. It’s the largest component to cost when welding. To run 2 lbs of wire with the $5-10 more for flux wire which is easily sourced anywhere including Harbor Freight, would not even get close to the cost of maintaining and filling the gas. I have to purchase, get my tanks certified and filled. None of which is cheap.

 

The original post posed a question whether it was worth fixing, my $0.02 is no. Just use it as a flux machine. That way the investment is about $10-15 for 2lbs of wire and start sticking metal. Flux must be run DCEN. Don’t put any money into the machine. This allows you to test the machine without a large investment. I think you will be disappointed.

if your welder had a voltage dial for infinite control that would make it worth considering. Many times these old machines have aging caps. We are talking about 500 mF @ 50v or bigger and they cost too much to replace (if they even added these on this machine)... I have an old Century with infinite controls that need new caps, I won’t fix it

again you can find inverter machines that will work incredibly well for not much money and probably less than you need to invest in this thing to try to make it work. With a digital read out you can dial in exactly what’s needed for a given situation. Plus if it’s for home use the duty rating are fine on these small machines.

 

I have to purchase, get my tanks certified and filled. None of which is cheap.

I don't use my Mig, Tig or oxy/acet for any thing but hobby work so a tank fill last me a long long time. And almost always end up paying for the re-certification, think the last one was $85 plus the cost of gas. And due to the loss of almost all industry around here Airgas is my only supplier.

 

The original post posed a question whether it was worth fixing, my $0.02 is no. Just use it as a flux machine.

Plus there is probably a reason the gas system was removed in the first place. But then I still say it was a flux core from the factory, a picture of the back of the unit would clear things up fast though.

 

I don't use my Mig, Tig or oxy/acet for any thing but hobby work so a tank fill last me a long long time. And almost always end up paying for the re-certification, think the last one was $85 plus the cost of gas. And due to the loss of almost all industry around here Airgas is my only supplier.

I bought a couple lbs of brazing rod and Air Gas added a environmental fee on it. I told the guy only hazard is at my garage. WTF. Look for an American Gases. It was less than half without all those made up fees. I pay about $40 for 80 cuft of Argon instead of almost $100. I love my Argon for TIG.

 

Look for an American Gases

None around here. 10 or 15 years ago there were many different brands of welding suppliers here but the only one now is Airgas, so for gases I'm stuck. But they did exchange my other brand bottles with no problem.

 

What sort of material and thickness are you welding? My first machine tapped the transformer for 4 power settings similar to this and it was all but useless to get the voltage right. Anyhow I understand the challenge of getting an old machine working. Just tap it off the feed motor.

Make sure you’re DCEP if you’re running gas
View attachment 220087

that is a picture of my welder...exactly!

I have taken 3 semesters of weld class at the vo-tech. And I own a miller AC buzz box. So I have the heavier stuff covered. So I've had access to a good mig at work, and I'd like to add Mig for thinner stuff and maybe some metal sculpture. : )

"just tap it off the feed motor" ? you mean the gas solenoid?

 

Yes there’s a low voltage tap or even a separate transformer for the feed motor. You should add a relay between the switch and solenoid. Keep it separate from the feed motor itself so you don’t have issues with wire speed and feed.

 

that is a picture of my welder...exactly!

OK, those welders are a rebadged Italian welder. A Cemont or CEM brand originally, they are also being made today in China and sold at Harbor Freight.

 

My first welder was the old blue MIG130 gas/flux from Harbor Freight, it was pretty bad. It was always too hot to weld light gauge Made even spot welding next to impossible.

 

I lucked out and got a demonstrator when they were changing models, a Millermatic 235. Not the new Multimatic but the old type. It was what they had at work so was what I really wanted, but wouldn't pay the money for just a hobby. Got it for around a third of the price because it was a demonstrator.

 

I lucked out and got a demonstrator when they were changing models, a Millermatic 235. Not the new Multimatic but the old type. It was what they had at work so was what I really wanted, but wouldn't pay the money for just a hobby. Got it for around a third of the price because it was a demonstrator.

Hey All! I'm back again with some new questions. So All cleaned up and half way back together. By tracing wires I thought I had figured out that the trigger sent current (from the weld stinger) back to a board that controls the wire feed motor. So tonight I powered it up on LOW (2 rockers to give a total of four amperages (?)) and jumpered the stinger to the connection on the wire feed board and it worked! The pot seems to control the variable speed OK.

So here's my new questions. When I did the jump connection, a large "box" clicked and something in it moved back until I broke the connection. A connector at the top of the "box" says 110V. could this be a solenoid for weld current? And could I piggy back the same to operate a new gas solenoid?

If you haven't been following along, the welder is a1980-1990 MAC WS1110. NO SOLENOID for the gas. A mechanical valve in the handle. Which, along with the original regulator, does not work.

Also I now have a new regulator with the ball float so that's good. And a newly swapped bottle of AR 75-CO2 25. And a new 2 lb coil of solid .030 steel wire. So what about the clicking box. (?)

 

My guess is the big click is the power contactor to switch on the weld power. I am thinking that the shield gas needs to come on a bit before the arc strikes so that the weld will be shielded. So you would need to add a time delay relay to delay the wire feed and the arc power just a bit. I suggested quite a while ago that a check valve at the "weld stinger" could prevent the gas in the hose from bleeding off between welds. Certainly there would be a fair bit of adjusting needed to get the pressures just right, but it could result in some savings on shield gas. Others claimed that I was totally goofy for having such an idea. But it is worth considering.

 

MIG does not need pre flow, just a sec or two post flow, especially with the valve at the gun. ARC needs a split second to develop. Technique also helps.

 

A mechanical valve in the handle.

Is it posible to get a picture of the stinger handle? Or possibly the valve you keep talking about that is in the handle. This stinger is unlike any thing I've ever heard of or seen. Where does the gas go into the stinger?

The *box* marked 110V, can you show a picture of it too?