I have a Wilton shop king with 4" wide jaws. The screw on it is missing a chunk of metal about 4 threads long an 1/2 way into the screw at the deepest point.

I have never seen anything like that. I originally thought it was over tightened but the handle is straight. I would think the handle would bend before the screw looses a piece. So that makes me think poor manufacturing. Truly I have no idea why and those are just guesses.

I thought about repairing it, an need some feedback. I was thinking I could tig weld several passes. Once I have the area built up I could take a lot of time with a file an shape the threads.

It would just be a light duty vise for my own shop. Of course that's when I get a shop again. I got it from my buddy for free, an it just sits in our shed. Worse comes to worse I just take the jaws an swivel for another vise down the road. It would also be good to practice tig welding something besides aluminum.

Any input is appreciated.   

Nothing to loose but your time. It would be good experience. The weld may be stronger than the rest of the screw.

Yeah, you might as well give it a try. It does make me wonder though what could have happened to cause the chunk to break off. Can you post a picture of it?

I could have been hammered on when clamping something in that [position.

Thanks for the motivation. I think that's what I will do. I just have to dig it out of the shed.

Since you asked for suggestions my young friend, my first would be to do some measuring of the rod and see if it's a standard Acme thread.  If it is you can buy a 3 foot piece from McMaster for a lot less than it will cost you to try rebuilding what you have.

Second suggestion would be that you grab a chunk of acme thread rod from something and practice your planned technique before you tackle the vise.

Third, did you ever learn to weld up to a carbon plug while you were in school?  I'm thinking if I was going to try TIG on an Acme thread I'd invest some time seeing if I could fill the areas not to be welded with a mix of carbon dust and a glue and then cut the thread area out with a die grinder.  It might stink like roasting a skunk during the weldup but it's going to save a lot of grinding to get to the thread you want.

Aunt Phil-

I have yet to actually dig the vise out, from somewhere in the back of shed. I went over to the shed an didn't have the key with me so it will be another days task. With that said I have not measured the thread.

My tig skills are not perfect. I don't do any tig at work on stuff that goes out. I mig alluminum daily, but thats not rocket science. I practice tig welding a few times a week on my lunch break. As long as I bring my own electrodes I can practice on anything in the scrap bin. Almost everything is alluminum, but some mild steel.

Honestly it's not meant to be a precision repair that lasts a life time. It's just one of those things I was bored thinking hey I wonder if it would work. I already have a broken vise an a full tube of lincoln ER312. It's not the perfect rod but of what I already have it's the best match. I don't wana have to buy anything for a vise I don't really need.

I have never done carbon plug welding, nor do I know much about it. I never finished school for welding either. I will go back when money allows.

The short version-
Carbon has several unique properties, 2 most important to welding are it's electrically conductive and unlike damn near any other element, SHRINKS rather than expands as it gets hotter.

Carbon is a repair weldor's best friend and a machine tool operator's worst enemy because a weldor worth his stinger can build repairs that eliminate most of the machining.
By shaping the carbon to act as a mold, a weldor can easily build a tooth back onto a gear rather than build a pile and let a machine tool operator carve it to the shape of the tooth.

Carbon is easy to shape, and can be clamped into place.

On the down side, carbon is single use, and filthy to work with.

BTW Nola, welding is something you NEVER stop learning.  I been burning up metal for 50 years and I'm still learning.  Damn little of the learning was done in any school.  A weldor has the job completed in his head before the machine is turned on.  A welding machine operator is just somebody behind a mask repeating day after day.
From what you've posted you got the makings of a weldor inside you, a few thousand hours of practice you'll be a mechanic.

Measure the thread. I have a couple lengths of acme threaded rod in my shed. If it is the same, I'll cut you a piece and you can fix the whole thing, like Aunt Phil said.

Aunt Phil- thanks for the knowledge. I am gonna look into it as it sounds pretty cool an usefull in some applications.

I know I have a lot to learn, mostly time under the hood is what I need. I have learned more in the real world version of welding from guys I work with then I did in school. It was a lot of theory at the local community colloge an welding on 6 inch pieces over an over again. No real world application. I learned a good amount about layout. I think school can help but you need more then that to be successful. Real world application is everything. I get so frusterated when someone boasts about there 4 year degree, yes a degree or certificate can be helpful but can you apply it in the real world. I think of anything you need dedication, good work ethic, an some good morals to succeed in any career.

Quote from: keykeeper on March 01, 2015, 07:23:28 PM
Measure the thread. I have a couple lengths of acme threaded rod in my shed. If it is the same, I'll cut you a piece and you can fix the whole thing, like Aunt Phil said.

Thank you very much. I will report back when I get it out.

Nola you got a handle on the situation, and a pretty good grip on the handle.
Like I told you, the weld is made in the weldor's head before the machine gets turned on.  There are always multiple ways to do a job, and as time goes on you learn what the best is.

School is where kids get to spend 4 hours making a 1 minute weld.  The real world is where school children learn a job is worth exactly the minimum time it can be done right in.  The Degree in the picture frame is just a ticket that gets you in the door to watch the movie.  Degrees on protractors and thermometers are worth a hell of a lot more in the real world. 

QuoteThe real world is where school children learn a job is worth exactly the minimum time it can be done right in.  The Degree in the picture frame is just a ticket that gets you in the door to watch the movie.  Degrees on protractors and thermometers are worth a hell of a lot more in the real world.

Well said, Aunt Phil!

Quote from: Papaw on March 02, 2015, 02:12:36 PM

QuoteThe real world is where school children learn a job is worth exactly the minimum time it can be done right in.  The Degree in the picture frame is just a ticket that gets you in the door to watch the movie.  Degrees on protractors and thermometers are worth a hell of a lot more in the real world.

Well said, Aunt Phil!

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