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welding alum tubing

bobnoffs

Well Known Member
hi all,
i am fitting aluminum flanges and a piece of tubing and need a way to lock it all in position to take to the welder. i was thinking of a little epoxy along the joints in a few places. after the welder tacks it rigid he could clean off the epoxy with a wire wheel. anyone got any other ways to do this? think my way will work?
thanks for any input.
 
hi all,
i am fitting aluminum flanges and a piece of tubing and need a way to lock it all in position to take to the welder. i was thinking of a little epoxy along the joints in a few places. after the welder tacks it rigid he could clean off the epoxy with a wire wheel. anyone got any other ways to do this? think my way will work?
thanks for any input.

I weld quite a bit and would not want to clean epoxy off particularly...
A simple single-use wood JIG would be preferable to contaminants on the metal.
IMHO
 
I agree with Kentlik. I too, weld a lot at work for a living and the hazards of burning substances that are not cleaned off are very hazardous. The risk of some epoxy getting in between the joint and not be accessible to proper cleaning is a real danger.

The jig is one way.

Alternately, you could fit the parts really well and mark them in place so you just line up the marks when taken to the welder and tack weld them. Return home and test fit. If all is well, go back to the welder and have him finish the welds.

None of it is 100% reliable as the metal will move and distort during the welding. The only way to do it once reliably is to hire a portable welding service, while the pieces are firmly clamped into position and fully welded in place.

Good Luck!
 
I weld quite a bit and would not want to clean epoxy off particularly...
A simple single-use wood JIG would be preferable to contaminants on the metal.
IMHO

I dont weld a lot, but enough to be called an above average hack and I agree with kentlik. AL is temperamental with cleanliness (not as bad as SS however). I suppose the welder could grind out the epoxy- its ok, but not optimal.

You ought to ask the welder what he can tolerate really. It also depends on what the part is being used for, or what stresses it'll encounter. AL welds are not as strong as the parent metal (steel is the opposite), so application will play a part in his decision about what you ought to do for him.........
 
Aluminum Cleaning

Don't use the epoxy!

Aluminum needs to be extremely clean.
Using stainless steel wire brushes is step One> Step Two-acetone wash.

Learning how to TIG aluminum right now.

At first; Could not get the ARC started. Cleaned the aluminum again, and was able to finally start welding.

Best to ask the welder what he prefers/transportation ideas....

Mike
 
I would mock up a wooden part to fit in final location. glue all parts. Then make a Jig to fit the wooden part. Fit your finished parts to the jig and weld up...... Now you can make the same part over and over.

On location is far easier but not always practical.

Update...... If there are only a few simple parts, just jb weld them and then make the jig and another set of parts for the finished item.
 
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AL welding

hi all,
i am fitting aluminum flanges and a piece of tubing and need a way to lock it all in position to take to the welder. i was thinking of a little epoxy along the joints in a few places. after the welder tacks it rigid he could clean off the epoxy with a wire wheel. anyone got any other ways to do this? think my way will work?
thanks for any input.

Don't contaminate the AL with epoxy. Use hose clamps clamps or secure it to plywood somehow....?? Hard to say with out seeing what you have.
 
Bob,

I think you would be better served if you were to use a few small strategically located pieces of duct tape to hold the parts together so the welder can lay down a couple of tack welds on the parts. Once the parts are secure, the tape can be removed and any leftover adhesive residue removed with a good scrubbing using Acetone or Alcohol prior to finish welding.
 
Agree with all of the comments above regarding jigs, anything will do to hold it until tacked. Depending on the shape of the parts, there is also PET welding tape https://youtu.be/KV3rLBetM4I. Have also seen parts "tacked" with the smallest amounts possible of cyanoacrylate (crazy) glue. The torch just vaporizes the tacks. YMMV.
 
thanks guys , a lot of info i never thought of.
the u tube with pet tape was good. a fabricator demonstrates several tapes for holding pieces. masking tape even works but clean up is a pain. the pet tape doesn't burn and comes off with no residue left behind. gotta get some of that.
 
Bob -

Just had a thought which I feel may be an eloquent non-adhesive solution for holding the aluminum pieces together for welding.

You mentioned the pieces you want to weld have flanges .... my suggestion is to get a handful of strong Alnico magnets and place one magnet on the flange of the part to be welded and a second magnet on the outer side of the aluminum it is to be welded onto. The force of the magnets pulling towards one another should keep the two pieces held snugly together while a couple of tack welds are laid down.

Sounds good in theory
 
I weld almost daily, can't say anymore about how important aluminum is to be clean.

I would mark it best you can, whoever you have weld it take it to them to tack it, bring it back to verify it is still good. 2 steps but is much better than the 2nd step being cut it all back apart.
 
Sounds like a great excuse to buy that TIG welder you wanted for xmas but didn't get.

After years of talking about it, I finally bought a Lincoln TIG 200 at Sun-n-Fun last time at the Lincoln booth for around $1250 IIRC with no tax and free shipping. Great little machine.
 
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Back in my industrial days, we aluminum brazed 3003 tubing for automotive A/C fittings for making hoses. Worked well.

Tom
 
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