Alumaloy

[sun of sand]

Never used this stuff nor have I ever welded anything
Not that type of dude

Has anyone used it
Can it really be used to butt joint
How strong will that joint be? This will be used to repair to a clamping mechanism so it must withstand some minor
Squeezing? probably less than .5mm

I would take the ends to be welded and file away on each to create a V shape between the two and then fill in the V with the weld material.
Perhaps not exactly a butt joint by definition but this has to be stronger

Then grind, sand and polish to match the original shape. I'd rather not have a blob of material overlapping for "extra strength"

 

[Greg_E]

I think on anything that clamps I would find a machine shop that welds aluminum and take them the pieces.
http://www.merchantcircle.com/directory/NY-Rochester/category/Home.And.Garden/Welding.Services

 

[Bryce Parker]

I'm not sure what alumalloy is, but there are a few products on the market to solder, braze or weld aluminum a wire feed or TIG welding machine.
None of them will give useful results on stressed components...
Agree with the post above, take it to someone with TIG or wire feed equipment and a fair level of experience. Even then the part will not be comparable to a new one!

 

[sun of sand]

Thanks
Thanks for that merchant search thing, too

I'm leery of machine shops around here -based on my 1 experience-
I've taken a bicycle part to a shop before
All that had to be done was a drilling out of a screw section siezed in aluminum
Well, he drilled it out but enlarged the hole pretty well, too
That one part was worth about $200 and I tried to convey the importance of a neat job
Had to stick in a fat screw and reshape the head to appear as an original. Hole is oval.

I did another much longer screw in the back wheel dropout myself with a hand drill and a level
I drilled all but a sleeve of the screw
Tapped the sleeve and screwed in an original screw.

I don't think they care about such small $15 jobs.

I'm giving this crap a shot and if doesn't work I can just grind off the alumaloy and give it to a shop
I can probably refinish that other bicycle part while I'm at it.


I wonder if I could just form a block of alumaloy and shape it.

 

[Greg_E]

Over sized holes in aluminum are fixed with a product called a helicoil. They work great when used properly. Also known as a thread insert or thread repair insert.

If you know anyone at RIT I'm almost certain that they have the welding equipment in the art department for sculptures. Probably get a student to weld it for free.

 

[sun of sand]

I had researched helicoils and thought about using one but
This was on a front derailleurs set screws. Very tight space.
But the real problem was that it would show. This was a classic and rare component so I didn't want something like that even if the only time you ever saw the repair was after taking the screws out
I made that known. I didn't know what a helicoil was beforehand but I knew I wasn't going to be ecstatic about a large hole. that's just what I got. Large, oval hole.

I know past students of RIT.

I'll see what can be done. I ordered some alumwhatever and might try out JB Weld tomorrow just to see/feel the stress load.

 

[bdial]

I got a bike shop to helicoil the cable clamp on one of my front derailleurs a couple of years ago. It's a Campy derailleur, but not particularly rare, though old. They did it at a loss because they had to buy a Helicoil kit for about 70 $'s or so. But he figured he'd have the parts for future repairs. Permatex makes a thread repair kit that's basically epoxy. You spread the stuff in the hole, then thread in the fastener. Good in theory, but it didn't work well for me, and I don't think it would work well on a derailleur cable clamp.

 

[Greg_E]

There was one welding shop that said free pizza at lunch time, that suggests they like small jobs.

 

[sun of sand]

Or that the chef dabbles in metalworking while the pies are cooking

I'll call around in a couple weeks.

 

[Greg_E]

Well that was the other choice is that while the pizzas are in the oven the guy breaks out the welding gear to make a few extra bucks.

 

[BOBBYD]

Alumaloy is great stuff and very strong when used right, my son and i work on motorcycles and have used it. Follow the directions and you will be happy and proud of yourself for fixing the item