Welding Tips and Tricks

I've had a Miller Thunderbolt 225 AC/DC for 20 years and done lots of little stuff with it. I use DC only and have never removed the leads from the machine. I decided to get new and longer leads to make things a bit easier. The push in ends to the machine have evidently corroded or got stuck as I couldn't get them out. After (too much) twisting the positive came out but in doing so I broke the wire from the transformer to the back of the positive lead where it mounts to the case. It's about 3/16" square that looks like aluminum. I've done a lot of soldering copper but not aluminum. Question is, can I solder a new copper ring terminal to the square aluminum to connect to the positive lead? I want to make sure this will work before i try it.

Launchteam1 wrote:I've had a Miller Thunderbolt 225 AC/DC for 20 years and done lots of little stuff with it. I use DC only and have never removed the leads from the machine. I decided to get new and longer leads to make things a bit easier. The push in ends to the machine have evidently corroded or got stuck as I couldn't get them out. After (too much) twisting the positive came out but in doing so I broke the wire from the transformer to the back of the positive lead where it mounts to the case. It's about 3/16" square that looks like aluminum. I've done a lot of soldering copper but not aluminum. Question is, can I solder a new copper ring terminal to the square aluminum to connect to the positive lead? I want to make sure this will work before i try it.

Welcome aboard!

You can, indeed, do this. My suggestion would be to tin the aluminum with solder first. Get it clean as for surgery, paint it with an acid-flux, and use a butane micro-torch to get it hot and tin it with solder. Then, clean all traces of the acid flux off it, and you're ready to solder on the new terminal with a safer rosin-core solder.

More than one way to skin this cat, so this is my suggestion and others are sure to follow.

Steve S

How about soldering a ring terminal to solid copper, then using a split-bolt connector to hook to aluminum?

I like the split bolt idea. I'll assume they can handle the amps well? I've never used them so I don't know what they're capable of.

Launchteam1 wrote:I like the split bolt idea. I'll assume they can handle the amps well? I've never used them so I don't know what they're capable of.

The split-bolt will handle tons of current. I'd suggest using a barrier cream like No-Ox-Ide A or some similar dielectric grease to prevent electrolysis between the dissimilar metals.

Steve S

Otto Nobedder wrote:

Launchteam1 wrote:I like the split bolt idea. I'll assume they can handle the amps well? I've never used them so I don't know what they're capable of.

The split-bolt will handle tons of current. I'd suggest using a barrier cream like No-Ox-Ide A or some similar dielectric grease to prevent electrolysis between the dissimilar metals.

Steve S

Yes dissimilar metals will corrode quickly so maintenance will be needed.

I got the split bolts and No-ox-id. Do I put the no-ox-id on the wires FIRST and then clamp them in the split bolt or clamp them first and grease over the connection?

Launchteam1 wrote:I got the split bolts and No-ox-id. Do I put the no-ox-id on the wires FIRST and then clamp them in the split bolt or clamp them first and grease over the connection?

Put it on first. It doesn't take much, but too much hurts nothing.

Steve S

Launchteam1 wrote:I got the split bolts and No-ox-id. Do I put the no-ox-id on the wires FIRST and then clamp them in the split bolt or clamp them first and grease over the connection?

Put it one the conductors first, then reef down the split-bolt and put a light coating over it, to just make sure the wires are covered. No need to drown the whole split-bolt.

Finally got time to work on this. The split bolt idea worked great. Thanks for your help and ideas.

Great! Glad you have it sorted out, and that we could be of help!

Steve S