Unusual welding problem

[Stan in Oly, WA]

A student had a problem with a small table she made that I haven't been able to think of a good solution for. The table (more of a piece of art than a functional table, really) has a top made of 3/16" steel plate in the shape of an artist's palette. There is a bracket welded to the underside with a small, coarse threaded lag bolt sticking down so that a cutting of a branch with three limbs can be attached for legs. After the bracket was welded in place, the table's top surface was polished to bright steel, then heat treated to bring out straw, and gold, and reddish brown colors. Unfortunately, she must have neglected to preheat the steel before tacking the bracket in place, and got the typical good looking but inadequate weld that inexperienced users often get with MIG. After the table was finished, the bracket broke off.

The problem is that the bracket can't be welded in place now without ruining the colors of the heat treated surface, and I don't think 3/16" is thick enough to drill and tap without pushing right through. I suggested that she ought to look into using some kind of epoxy to reattach the bracket, but I'd be glad to get some other suggestions.

Thanks,

Stan

 

[Anonymous-0]

I think you're right to go with an epoxy like JB weld. You don't want to ruin the color of the table and it sounds like the bracket doesn't need a whole lot of strength.

Do you have a small piece of 3/16" plate you could heat to get similar color? You could put a little weld on it and see what it does to the plate. The weld might make a really cool color mark on the other side, kind of like stainless makes neat looking colors..

 

[dr sportster]

For things like welding in holes to remove door handles on cars and least affect the surounding area.I make a paper mache mix with newspaper. I got the idea from Eastwood Company that sold a product but had more fiber and such. Have one person rub the paper mache back and forth while someone else welds the bolt back on. { It is after all, an art piece so there is no right or wrong ]. I'm picturing she has it as a gold like finish as in heated stainless and will not want a blue spot . I don't know if she wants to chance it but that's what I would do. Don't give any garrantees. Hit it quick.
Stan you better do this for her yourself [with a disclaimer!]

 

[Adirondack case guy]

Weld a plate, say 3 inches in diamiter to the lagscrew head and then you have a larger flat surface for the JB to adhear to the bottom of the table.
Loren the Acg.

 

[wisbaker]

I'd make another plate 4"x 4", weld it to the legs and epoxy (JB Weld) the assembly to the table under side.

 

[old-9]

An old welder friend told me of using copper bar as a heat sink when welding holes shut. Another made a rig of a copper tubing coil, with water running through, to keep thin ss cool while welding. Try a scrap piece to see what works.
joe

 

[Stan in Oly, WA]

I agree with that approach, most of the time (finding a way to incorporate a mistake into the design so that it appears to have been intentional), but there are two drawbacks to that in this situation. Number one is that it's risky when she hasn't expressed a willingness to repolish the surface and heat treat it again if it goes wrong. Number two is that even if the cobalt blue color that welding is likely to produce on the table's surface is attractive, it's going to come through as all or part of a rectangle---the shape of the bracket. I'm sure she won't go for that.

Thanks for the suggestion.

Stan

 

[Stan in Oly, WA]

It's an interesting sounding technique, and one I'll tell her about in any case. I guess what it comes down to is whether she wants to fix it right at the risk of damaging the colors of the finish, or do it in a way that won't hurt the finish but might not be the best fix.

Thanks, dr.

 

[Stan in Oly, WA]

That makes sense. I didn't take a close look at the bracket because its configuration wasn't the cause of the problem, but if it doesn't already have a good amount of surface area as you're suggesting, I'll advise her to do that.

Thanks

 

[Stan in Oly, WA]

That's a good suggestion. I'll advise her to do that unless the bracket can already be used exactly that way. I didn't take a close look at it at the time.

Thanks

 

[Stan in Oly, WA]

Thanks Joe. Pretty interesting. The issue with it is pretty much what I said to stick welding and dr sportster---the artist may prefer to go with a less than perfect repair that won't risk hurting the finish rather than a good repair that might.

I may try the methods you described on my own test piece just out of interest.

Thanks

 

[Michael Soldan]

If its just a table I'd glue the bracket on with industrial epoxy,it will hold as good as a weld and not discolour her work.We use a glue for construction work that is incredible,you can glue concrete blocks together and you have to smash them with a sledge to get them apart

 

[Stan in Oly, WA]

Thanks Michael. That's encouraging. I'll let her know.

Stan

 

[Chip812]

I'm really surprised no one suggested making a bracket with the same contours as the original piece and then the welds will follow the outline of the original and look like it was done on purpose.

 

[Stan in Oly, WA]

Clever. I'll pass that idea along, too.

Thanks