Heard back that the serial number is HG039431. That doesn't come back in the manual search on the millerwelds site, but that should work out to the April 1976 manual.

 

It has a mechanical valve in the handle. If the valve works, use it that way until you can afford the update parts. My dad's 35s is the same vintage and still works fine.

Sent from my SM-G960U using Tapatalk

 

This is a sweet unit with the spot welder option.

You can update with newer tips and diffuser.
https://weldingweb.com/showthread.php?705562-Millermatic-200-GA-20c-gun-update&highlight=

 

My gun and consumables look different:

 

I was able to look at the welder tonight and decided it was worth the risk. I got it home, replaced the power plug and then stripped off about 100' of rusty wire from the spool and powered it up....fan came on, wire feed seems to work properly and respond to the dial, etc. It was missing the regulator, and I don't have the kind with just a nipple for the gas line, so I wasn't able to weld with it. I did strike an arc a couple of times just to see if it would, and it did. The gun and hoses/wires seem fine, but the shield over them is trashed, so I'll have to find a replacement...I'm thinking maybe large shrink wrap, or a short canvas cover like for TIG lines...I'll come up with something.

Time to order a regulator, work clamp and do a bit of cleaning so she's ready to go!

 

Looking at the miller manual, the gun side is 1/8" male pipe thread. To use bernard or miller parts you would need 1/8" to 1/4" male pipe thread brass fitting.

Look up bernard ds-1 diffuser and T series tips and choose a nozzle. Also need a insulator.

Used heat shrink tubing with adhesive to repair the gun cable assembly.

 

The gun side seems to be 1/8" female pipe thread. I would think a 1/8 to 1/4 MPT brass fitting would let me use the Bernard 1/4" parts, right?

Looks like a Bernard 4335 diffuser, 4323R insulator, 7400 series tips and a 4391 nozzle would make a complete package.

 

Yes on brass fitting.
Not sure on part numbers.

If you need the liner, get a .030 - .035 miller liner from ebay or welding supply store. They are about 15.00 or less.
Remove the brass back end, either unscrew or cut it off. Remove the bushing from old liner and reuse it on new liner. Used electrical line pulling lube to Install new liner. Cut new liner to correct length once brass adapter is install on the gun.

 

I got one just like your white face a while back and have yet to even plug it in. Missing a gun too but came with a nice regulator.

 

This is a link of discussion MM35 older guns.
https://forum.millerwelds.com/forum/welding-discussions/9616-retrofitting-a-millermatic-35-mig-gun

 

Thanks...I found that one as well. I have a regulator inbound today and I'm going to see if I can get it to weld with the original gun setup. The valve and switch in the gun seem okay, but it did need new seals in the valve. If it welds, I'm going to convert the gun to modern consumables and run it a bit. If not, I'll probably start sourcing the parts to add a solenoid and convert it to a modern gun like in the Miller forum discussion.

 

So the regulator got here late on Sunday and I didn't have much time to doing any testing. As soon as I connected it and opened the valve I could hear gas coming out of the torch, so I may not have put the new gaskets in the valve properly. Hitting the trigger did increase the sound of gas, but it wasn't flowing out the nozzle enough to be able to weld, so something is wrong.

I'm probably going to just convert it to an electric solenoid/valve setup and put a modern gun on it similar to the discussion linked above from the Miller forum. I've given it a quick cleaning, replaced the work clamp and pulled the wrapper off. I was shocked how clean it was inside...the picture was taken without any sort of cleaning done to the inside. I really don't think it got used much at all, and that fits with the story the seller told me...it was his grandfather's and sat in his barn.

 

Tweco used to sell a kit the adapted the welder for use with a tweco miggun. Gas valve could be mounted on the adapter or
inside the case. valve got its power from the weld contactor coil. talk to your local welding supply and see it they can order it or have one laying around.

 

Thanks. I've seen references to that kit before, and found some sites showing them available, but they're something like $265. I saw someone comment that Tweco doesn't list the kit, but sells all the parts, so they can put one together for you. The Lincoln adapter mentioned in another thread, along with sourcing my own solenoid and valve should be a lot less expensive and I think I'd be able to get it all together with a gun for less than what the Tweco kit alone costs.

I'm not trying to make any money on it, but would like to be able to break even if I sell it so my wife doesn't get mad at me :laugh:

 

Maybe this is an old information that you already know about but the gas solenoid (Tweco - MAK-353-S) is available from multiple online sellers but for $150, seems like all of them are united on the price. There is however an eBay seller that's selling the 120VAC (TLAK7-353-S) version for $40. I don't know how helpful that is for you, or if it could be adapted somehow.

There is also an online store (weldmart online) that has been mentioned on some forums as possibly having that solenoid and a MIG gun for a reasonable price. Worth giving them a call. If you were able to find the solenoid, maybe usaweld would have a gun that can fit?


Sent from my iPhone using Tapatalk

 

This is how my 35s came equiped when I got it. Think I paid $50 but I can't quite remember as it was bundled into a deal with a $50 Big Joe lift and Kalamazoo bandsaw. I'd get better pictures but the machine is burried at the moment. It has what appears to be a decent Harris Flow meter hooked up to the gas valve that’s sitting on the outside of the machine where the gun plugs in. Not sure of the gas valve brand. Also I haven't looked yet to see what the serial number indicates for build date and version. Any ideas just by looks if I have the latest version or some hacked work around set up?

 

I took the torch apart, put it back together and now I'm getting gas out of the nozzle, but the valve is still leaking even with new gaskets in it. I could push the trigger backwards and get the leak to stop, so I know it's the valve.

With that in mind, I grabbed a piece of scrap and ran a couple of beads on it. I have to say the arc is very smooth and I was happy with the results.

I spent a bit of time with the multimeter and found the circuit for the wire feed motor is 12VDC and easily accessible. It actually goes from 12V to 18V as the fine adjustment on the wire speed increases, but that shouldn't be a problem. I found a 12V normally closed solenoid/valve combo that looks pretty decent, and is reported to be popular for welder conversions, so I ordered one. I'm going to order the Lincoln adapter, a Miller 4-pin socket for the gun, and an HTP gun for it and see if we can't get this old girl back dancing.

 

Feed motor voltage changes with the weld voltage taps. The speed control is just a fine control. The whole circuit is across the weld voltage.
Just unplug the yellow jack and the motor will not run. It is best to wire the gas solenoid in parallel with the weld contactor. 24vac

 

Thanks....I have been meaning to come back to this for an update. I found exactly what you mentioned after I spent a little more time with the multimeter. Around the same time I bought a second 35S that had one of the original Tweco adapter kits on it and that uses a 24V solenoid off the weld contactor as you suggest. They ran it to post #32 and #44 on the terminal strip. I checked that with a meter and it's more like 27V, but within range for the second solenoid I bought. I hadn't used the 12V solenoid so I'm going to return that.

I went through the second 35S, put a new gun on it, new wall plug, new gas line, new regulator, tightened a loose capacitor, added a new spool of wire, gave it a good cleaning inside and out and then welded a bunch with it in all the taps and wire feed speeds. I have to say I was pretty impressed with the arc quality. I put it on FB marketplace and it was gone the next day. I have to finish the first 35S, but that should be easy at this point...hopefully get to it this weekend.

 

Just thought I'd follow up with some more details and a few pictures. I used a 1/2" thick piece of acrylic (cutting board from Menard's) as a backer and drilled holes to fit the gun adapter, gun trigger receptacle and power lead. The adapter fit wasn't very tight so I epoxied it in place with JB Weld from both sides and now it's rock solid. You'll want to use nylon washers between the bolt heads and the face of the welder to insulate the bolts.

I made a bracket for the gas solenoid/valve out of some angle iron and mounted that under the contactor. That gave a pretty smooth path for the gas lines and kept the wire length to the terminal strip reasonable. I pulled 24V AC for the solenoid off the terminal strip at positions 32 and 44.

There are two things you really want to get right with this conversion. One, try to center the new gun adapter as close to being in line with the wire feed rolls as possible. I used the original hole for the gun as a guide when I drilled the hole through the acrylic. Two, you'll need some of the old monocoil material that wrapped around the liner along with a short section of liner. As you can see in the pics, they used a length of liner at the back part of the wire feed bracket to guide the wire to the feed rollers. On the other side of the roller (front side) the bracket is drilled to a larger diameter than needed if you would just mount a piece of liner in it. The original moncoil was the liner with a plastic shell that slid into the front of the bracket, and was held by a set screw. If you just put a length of liner into the front section it will be out of line with the feed roller. Add a section of the plastic monocoil shell, then slide in a length of liner that goes from the drive roller to the end of the gun liner and secure it with the set screw. If you fail to do that you will get one bird's nest after another (ask me how I know!).

I think it turned out pretty nice and really like the way it welds....it's got a really nice, smooth arc.

 

 

Fun Stuff !! I used to sell these back in the 80's. The original spring trigger gun was terrible on gas control but they came out with a solenoid kit later and then the black face units had the gas solenoid from the factory and better gun and things got better after that. Nice Unit !!

 

Yeah, it was a fun project. I'm not planning on keeping it, but I'm not in a big rush to sell it. If I break even, or make $50 I'll be happy and just glad it didn't go in the scrap pile.

Actually, Miller started adding an internal gas valve/solenoid before the black-face 200. In the linked thread a Miller tech says that Miller added the internal gas valve to the model 35 in 1980.

 

Thanks G-ManBart.
I have a question for you. I have installed the same gun adapter kit (the Lincoln K3347-1) and I'm installing a Miller GA-20C gun on to it, but the gas keeps flowing out the back side of the adapter kit (inside of the welder). Are there different (optional), ends that you can screw in the back end of the GA-20C weld gun? I have a tapered end on it now that doesn't seem to seal off at the inside end of the adapter, so it seems as if all of the gas is escaping before it enters the sealed (gas) area on the gun.

 

Can you post a picture of the back end of the GA-20C....the part that connects to the welder? I'm certainly not an expert, but I'm sure one of us can figure out what's going ont.

 

Small or large amount of gas? small amount is normal coming from the liner.
any gas from around the outside of the power pin is a bad o-ring.
You can use a little soapy water and see where the gas is coming from.
If a lot is coming from the liner. pull the liner out of the gun. there should be about two feet or more of plastic covering the metal liner. This covering is to push the gas down the gun before allowing it to leak into the liner.
I think the GA 20c gun is obsolete and the liner and most of the consumables are no longer available from Miller.

 

This is the gun that I have been trying to connect to the adapter. The adapter has a hole on the inside of the part (per the 3rd picture) and I think that is where the gas is coming out?? The back end of the gun is tapered and it is threaded, so it's removable. Maybe there are optional ends that I could get to put on to seal up the gun right on the very back end?? I'm not sure.
I put duct tape over the sleeve on the inside of the adapter and plenty of gas comes out the front end (where the gun attaches to). I even stuck my little finger in the sleeve, (with the duct tape on the inside yet), and there seems to be plenty of gas coming out of the adapter. It's just coming out the back end near the tapered part of my gun. Maybe I need to get a whole new style gun??
Thanks again everyone for your help with this problem.

 

This is the gun that I have been trying to connect to the adapter. The adapter has a hole on the inside of the part (per the 3rd picture) and I think that is where the gas is coming out?? The back end of the gun is tapered and it is threaded, so it's removable. Maybe there are optional ends that I could get to put on to seal up the gun right on the very back end?? I'm not sure.
I put duct tape over the sleeve on the inside of the adapter and plenty of gas comes out the front end (where the gun attaches to). I even stuck my little finger in the sleeve, (with the duct tape on the inside yet), and there seems to be plenty of gas coming out of the adapter. It's just coming out the back end near the tapered part of my gun. Maybe I need to get a whole new style gun??
Thanks again everyone for your help with this problem.

I hate to say this, but the adapter is installed backwards. The gas port is supposed to be towards the front of the machine....sorry. If you look at the pics I posted you'll see the adapter has several sections that have been turned down with a couple of steps...that end needs to be towards the wire feed. The install was nicely done, so I'm sure you can fix it, but I know that was a lot of time involved...ouch!

 

It's a large amount of gas coming out the back end of the adapter, (in fact all of the gas seems to be coming out the back end, none out the gun tip at all). It seems as though the gas is not getting to the gum at all. Maybe your right, I may need a newer style gun?? If so, I want to make sure I buy the right one.
Thanks again for your input.

 

two things first the o-rings on the power pin are damaged. you can see pieces are missing. they must be replaced. Next measure with a small steal ruler.
from the center spot between the o-rings and the stop step on the power pin.
them measure again from the front of the adapter to the center of the gas port.
You also can remove the gas hose barb and look in the hole while pushing the gun in.
you should see the o-ring go by and stop just past it. one o-ring on either side of the hole. The black insulator block might be to thick. the hole might need to be larger so the power pin will seat correctly. Plastic should almost torch the adapter.

 

You know what, I thought that right away when I first was assembling it onto may insulator plate, but I second guessed myself and put it on as assembled. I bought it on ebay and the box didn't have directions with it, so instead of relocating the gas hose on the opposite side, (like I needed to do), and putting the plastic coated plug on the back side, I just installed it as it was sent to me. I wished they had included specific directions for this part, I could have saved myself a lot of guessing & a lot of work! I will take it apart and switch it around on Monday, when I get back to my shop.

I'll bet all you seasoned veterans are snickering at this rookie mistake I made!, (although I'm already 65years old, I am a rookie at rebuilding one of these welders). I guess it is kinda funny, after thinking about it!! I kinda feel embarrassed that I didn't pay more attention to what end the hole was on, (on the inside, per the 3rd picture), that supplies the gas on this adapter. Thanks again for all of you help on this project. I'll let you know what happens after I flip it around the other way.
I'll have-to rename my site: Wrong-way weld, (per the 1970's airplane pilot on Gilligan's Island!) :laugh:

 

Don't feel bad....the first time I had one in my hands it took me a few minutes to realize it had to be installed the other way after swapping the gas connections, so it isn't just you!

 

Thanks again everybody for you ideas & help on this project. I pulled it out yesterday afternoon,cleaned it up nice and re-glued over night. I got it re-installed today after the epoxy set-up nice! It was surprising to me how easy it came out of my insulation plate yesterday! Maybe the JB Weld wasn't completely set-up yet??

It's amazing how nice these things weld, after you put them together the right way!! :laugh: