Refurbishing an old Miller Thunderbolt 225AC

   / Refurbishing an old Miller Thunderbolt 225AC #1  

stravis

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Apr 17, 2009
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Location
Henderson, GA
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2009 John Deere 5101E Limited
Now that y'all have answered my plug question, on to the next phase.

I'm as green to welding as they come. For years I've wanted to learn. I live on and run a small farm. I have dozens of uses for one. I broke a bush hog mower at the mount Saturday and long story short, I've been given an old (very old) Miller Thunderbolt 225 AC style HD-6. According to the Miller website, it was built in 1973 or 74. It has been sitting unused since 1993. I'm told it worked when it was put up.

My shop is wired with an RV plug and I'm building a extension / adapter cord for a 6-50 receptacle tomorrow night. Before I plug this thing in, I wanted to run it by y'all.

I downloaded the manual from Miller's website and followed the maintenance instructions to grease the shunt block. I oiled the fan bearings. The fan turned fine and had no wobble to indicate a bad bearing. I cleaned it all up inside and blew out all dust. Checked the wiring for obvious shorts. Cleaned connections. Everything looked to be in running order to my untrained eyes.

Anything else y'all can think of that I need to do prior to trying it out? Do I have any chance of this 38 year old welder running? Any other tips?

I intend to clean it up more and repaint if it works. Here's a pic.
2011-08-15_20-00-24_107.jpg


Thanks in advance for any help you can offer.
 
   / Refurbishing an old Miller Thunderbolt 225AC #2  
I bought a used, 30 year old lincoln AC-225s, hadnt been run in years, plugged it in, and it worked perfectly, didnt have to do anything. I am sure the miller will work just fine.
 
   / Refurbishing an old Miller Thunderbolt 225AC
  • Thread Starter
#3  
I hope you're right. Thanks for the reassurance.
 
   / Refurbishing an old Miller Thunderbolt 225AC #4  
That looks mint compared to some of the TB's ive used in barns.

Plug her in, ill bet it works just fine.
 
   / Refurbishing an old Miller Thunderbolt 225AC #5  
That thing is actually in very good condition for a welder that old, better then my lincoln.
 
   / Refurbishing an old Miller Thunderbolt 225AC #6  
...Do I have any chance of this 38 year old welder running? Any other tips?...

That welder will more than likely still be working for your grandkids 50 years from now. Most dependable welders ever made are AC only buzzboxes from Lincoln or Miller. They are so simple that there is very little to ever go wrong with them.

An AC buzzbox is the perfect addition to a backyard shop as it is actually a very versatile tool. Obviously it can weld metal. It can also cut metal - stick some 6011 in the stinger and crank up the amps and you have a way to cut metal. Also build a twin carbon arc torch and you have a way to heat metal as hot as oxy acetylene can for nearly free. Twin carbon arc is NOT for cutting metal though.

Not sure how much stick welding you have done but 7014 runs great on AC (commonly called idiot rod since it almost welds itself), 6011 is handy for dirty rusty metal, and 6013 runs well too but I use it on thinner metal and applications not requiring maximum strenght. These 3 were always my goto rods. After you get good then give some 7018AC a try as well.
 
   / Refurbishing an old Miller Thunderbolt 225AC #7  
Not much to poop out inside of an old SMAW machine except the switching contacts and if its ac/dc, the rectifier. It's most likely copper wound (big plus) and the old machines are way overbuilt.

The biggest plus is it was MADE IN USA by Americans, not in some third world hovel by a cooley making 50 cents a day and a bowl of rice.
 
   / Refurbishing an old Miller Thunderbolt 225AC #8  
As I recall, there are warnings in the welder product manuals that they can throw sparks 35 feet. There's been some discussion here about fires starting after someone has closed up shop for the day. So when you fire it up, be careful where you weld and keep an eye out.

Good looking welder, too.
 
   / Refurbishing an old Miller Thunderbolt 225AC #9  
Anything else y'all can think of that I need to do prior to trying it out?

I recently picked up an older Miller Thunderbolt clone. Not sure if it was done at the factory or by some idiot later on, but I would recommend checking where your welding leads go into the two plug jacks (You will need to remove the little plastic cover which is simple). On mine, none of the insulation was stripped off the cable and the only connection was made by where the set screws barely pierced through the insulation - this was a marginal connection and my leads were getting extremely hot due to it.

Welder worked much better after I stripped the insualtion back a little bit so the leads went into the brass receptacle for a good proper connection.
 
   / Refurbishing an old Miller Thunderbolt 225AC
  • Thread Starter
#10  
Thanks for all the advice. There were a few dirt dobber nests inside and even about 3 feet of plant material. It cleaned up well, though. I didn't see where any mice had been chewing wires. Everything appeared fine to me. There is some surface rust on the cover and face, but I'm not worried about that.

I bought some 6013 to play with because I heard it was easy to strike. I don't intend to do any structural welding with it, just practice. I appreciate the tips on rods to use, rankrank1. I'll double check the lead connection as well.

I'll let you all know how it goes tomorrow.
 
 
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