O/T Welding Aluminuim

[Frank]

Hi all: I figured I could give it a shot, if anybody knows about welding Aluminium. What I had was a major screw up on a very elaborate part. It was completly finished, and all I had to do was put an "O" ring groove in the top, and used the wrong cad file, to generate the toolpath. "BIG MISTAKE" The boss says that welding that groove closed .104 wide x .052 deep would generate too much heat and screw the close tolerances that have allready been machined. I'm hoping that there is some way to weld it and direct the heat in 1 general area. And save this part.

 

Any suggestions would be appreciated.

 

Thanks,

Frank

[George Hardwick]

Maybe depends how big the parts is, use TIG and dont be greedy do it in little bites and let it cool between.

[Harryman]

Aluminum conducts heat like mad and is subject to hardness and dimentional change from welding.

 

How precise is this part?

 

Will it be anodized?

[Frank]

Figure +-.001 on some very critical dimensions. We have a lot of work hours in this part, and it just seems like it would be worth the try. The boss wants to just scrap it and start over.

[Philcott]

Frank,

 

Is it possible to cut out the damaged area, press in an aluminum blank, then face and re-cut the "o" ring groove? Just a thought.

 

Phil

[Brendan P]

quote:

---

The boss wants to just scrap it and start over.

---

IMO,the boss knows what he is talking about.

We do all kinds of welding/fab./machining here and I know for a fact that you part will be very distorted all over.

Not to mention that fact that in most situations,you need to get written approval from your customer to even attempt to sell them this "re-worked" what used to be a gem!

[Harryman]

+1 Phil

 

Heat kill, BAD

[MACHINEMASTERG]

+1 to phils idea.. ive welded aluminum to fix things in the past turns out ugly also anodizing will show... sometimes boss is rite make it over it always runs faster the second time after you mess the first one up ...been there done that

[Keithm]

I have to agree with your boss.

[Lars Christensen]

+1 Philcott

 

If you can upload the part to the FTP site, then we can all take a look, and see if there isent a good way to do a insert.

 

Lars

[Frank]

The groove is too close to a cylinder, so putting a patch on it wouldn't be possible. The cylinder also has a metal sleeve pressed in, so that causes another problem while welding.

[Roger Peterson]

I certainly don't see any harm in trying since the part is scrap anyway, as long as the customer will take a welded part. Preheat the entire part on a hot plate and take your time welding at the lowest amp setting that will work. I would heat up a practice block before jumping in. With every precaution I'm 90% sure you'll end up scrapping it out anyway.

 

 

good luck

[chris m]

Frank

 

Bummer on the goof, that sucks. My last life was at a shop where we ran aluminum almost exclusively and the torch was a VEEeeeerrry common repair tool when the guys said 'oops I just counterbored the wrong side of this $3,000 chassis'. If you are gonna junk the part anyway I'd take a whack at it but you have several things to consider first:

 

1) If the part isn't 6061 make sure that it is weldable as some Al alloys do not react to weld positively

 

2) If the part is going to be anodized, chromated, or subjected to any other acid-etch process the weld will show up like a sore thumb; this needs to be considered

 

3) If there are any holes or other features within an inch or so of the welded area of the part they will pull toward the weld when it cools

 

4) TIG is the only viable option, must be performed by someone who knows what they are doing, and the parts must be absolutely clean

 

Good Luck

 

 

C

[Guest CNC Apps Guy 1]

quote:

---

...4) TIG is the only viable option, must be performed by someone who knows what they are doing, and the parts must be absolutely clean

...

---

+1000 You'll want the smallest torch you can get your hands on, your Tungsten 'trode shoudl be SUPER sharp at the tip too so the arc doesn't get so large. I'd suggest a Square Wave TIG if you've got one in the house. MIG is absolutely positively out of the question also in case you were wondering.

 

JM2C and HTH

[Frank]

http://www.snapfish.com/slideshow/AlbumID=...0979/t_=5978627

 

It's not a great pic, but you can get the just of it. Thanks for the replies.

[Frank]

http://www.snapfish.com/slideshow/AlbumID=...6387/t_=5978627

[Charles Davis]

There are a ver few specialty welding shops that can do a great job of this. One here in San Diego called Clint Precision Welding saved my tail a few times.

[Harryman]

quote:

---

Clint Precision Welding saved my tail a few times

---

They WELDED your tail back on?!!

[Guest CNC Apps Guy 1]

 

ROFL!!

 

That musta hurt!

 

[Frank]

I definatly NEED THAT WELDER, because my tail needs to be welded

[Charles Davis]

That's a hoot.

[Jack Mitchell]

I would core the hole about .25" radially larger, then press fit the same material with about .003 interferance, then install the hole detail accordingly.

 

If this won't work then the part is scrapped anyways - give it round two and learn from the mistakes.

 

One place I worked at, we had to triple draw the mold inserts; it's the part where we sent them out for engraving for an automotive customer. The inserts returned after the final draw and the heat treater hardness tested the face

 

We had a magical welder that was good with H13 perform the miracle to save this job, prior to this I was unaware how often this practice occurs.

 

Regards, Jack

[George Hardwick]

Did not want to butt in, but some of you programmers would be horrified how often this happens on the shop floor. As I say if your carefull with it no probs..

But then this is the UK....

[SledGeek]

Tig would be the best choice if possible. Also remember once you start plasticizing alim. or steel it may,depnding on what it is, change the temper of the metal.

I used to use alot of spray welding applications(unfortunately) when regular welding could cause too much heat.Good for build up and fill in but not very precision.I beleive the source we used was in Metro Detroit area. Been 6-7 years so i don't remember who, but could probably find out...

[Müřlıń®]

Figure +-.001....if inserting wont do....

 

 

....the part is scrap....srry

 

Way too much heat....

 

 

Murlin