Welding Tips and Tricks

A friend gave me the handle and screw assembly to a large vice. The bar is about 1 inch solid with threads in good shape but it was split in half somehow. He asked me if I could weld what appears to me to be a cast material. What to use? DC tig? Settings? Do I need rod for cast material? Would this call for tig brazing and would it be strong enough to hold under pressure? Any suggestion would be appreciated.

Any chance of a pic?

Hard to visualize the job so a picture will help as already mentioned - a vice though can be cast iron or cast steel if it's a better quality one so a spark test to confirm material will help get good answers - both are possible to weld with Tig but you need to know.

I will try for some pictures later today. Thanks

It's worth a try to repair it, for the practice and experience.

It sounds to me like the draw-screw is fine, but the cast "arm" of the vise that the screw draws in is broken? If so, I'd vee it out fully, pre-heat the parts in my gas grill to a good 450+, and TIG it up with hi-nickel (old piston rings... Thanks, WerkSpace), and slow-cool it buried in a pile of sand or Vermiculite.

Good luck. This can be done, but it's not usually a beginner weld.

Steve S

Here are the pictures of the vice screw. I'm not sure if that is the right term. Comments please.

I sincerely hope someone comes up with a solution for you because to me that's a throw away.

Go the oxy acetylene route and bronze it. Tig brazing is a bit more of an experience thing.

It's an Acme thread. It definitely won't be cast, but it probably is hardened, looking at the crystalline structure through the fracture point.

Acme threads are quite standard, and you may be able to purchase a length and then just cut and weld the existing handle to the thread, then you don't have to worry about exact matching the thread pitch, which will be a problem.

There are products available on ebay:

http://www.ebay.com.au/sch/i.html?_from ... w&_sacat=0

My suggestion is to replace the thread portion with a new same size diameter and pitch acme thread, even if you have to fabricate a new handle section, bored to the OD size of the thread, insert and bronze weld the two together.

I have also seen Acme thread rod on McMaster, and you might even be able to source some through a local metal supplier (though that might a bit of a stretch!)

That's the kind of stuff an old boss used to have me save.

Grind a double bevel, weld it up, re-cut the threads by eye with a hacksaw, file, and cut-off wheel.

It will likely take several hours - but I wasn't getting paid much back then, so the boss didn't care

Good luck

(if possible, replacing it is the better choice - but doesn't make for a cool story)

May be weldable...

But perhaps you have someone with a lathe nearby? Make a new one.

I would say definitely YES. Reason I know this my brother broke a vise he was beating on handle trying to make it tighter cause thing he was trying to hold kept spinning. Needless to say He broke the threaded acme rod he wanted to hide it from dad all we had at our disposal to weld it with was a 120volt Lincoln weld pak I just recently bought. (First welder I bought with my own money). I V grooved the rod and using flux core welded it back together. I hate flux core, I admit it I am a TIG snob anyway some time with a dremel with abrasive cutting disk to cut threads and it was back together. This was 20 yrs ago that vise is still in use my brother has it now. He don't beat on vise handles anymore with sludge hammers

Measure it up and message these guys
http://stores.ebay.com/imsrv/Lead-Screw ... 4512483011