Weld a cracked rim or replace? 03 2.7t
 

Took my car to the local tire shop after having to fill it up several times over the course of a week. Was told the seal was bad and they "fixed" the rim and it should hold air. Few days later tire was almost flat again.
Took back to same place and said they found a very small crack by the seal.

My local "Car guy" said he could have a friend Tig weld it for me while an old friend who is a professional construction welder said not a good idea.

The rims are stock with the 2.7t.
Can be seen here:
http://www.wheelcollision.com/audi6a.htm
Part #H 58764

Thought about replacing all the rims any way as the previous owner like to grind them on the curbs. Also thought about having them refinished but haven't checked costs.

Other Idea I had was to call the local scrap yards and try to locate a replacement.

Never bought rims before. Read about these and from what I can tell options are limited because of the brakes.

Should I just invest in a new set all round? or Repair the cracked one?

its cheaper to find new rims, sometimes you can find really good deals on Craigslist and eBay if you just look around.

but always make sure the offsets are corrects. one time i bought Audi TT rims but it turned out there offset was like 110 not 112 or something and they would not fit my Audi 100...but they fit my Chevy cavalier which was a plus I guess

the ones in the picture on the left of my Sig was a Craigslist buy, I got them for 400 dollars(all 4) which was cheaper than having rims refinished 150 a piece.

Replace. WWW.wheelcollision.com or just google the p/n on your wheel. Chances are they can't repair your wheel if it's cracked on the outside, inside probably.

replace them. on ebay all 4 rims for 17'' are running around 400.

One more vote for replacing instead of repairing.

I repaired the same rim twice for bends... Should have dumped it initially. Took 2 tries to realize once it's cracked/bent, they're garbage.

Welding is a bad idea for several reasons...
 

...the weld metal will probably not bond well with the alloy the wheels are made of, and the heating will change the properties of that portion of the wheel. Do you really want to mess with the strength/balance of such a critical rotating part?
Plus, as previously pointed out, they are easy to find in Junk Yards and on e-bay. Or use it as an excuse to get some slick new ones...
Jim

Thats what my welder friend said too. Makes sense to me. Going to call the junkyards first to see if I can find an easy solution.
Was kinda hoping since it was a small crack it would be an easy fix. Can see how it would be a problem later.
Did plan on upgrading the calipers and brakes. Dont have alot of time to do the research on it. Know they take into account with rims and offsets. Just get a cheap doughnut for the trunk until I get everything sorted.

Yeah, the problem with welding on any type of Aluminum alloy is that you have to pre-heat the metal to get the weld to flow/spray properly, but the metal spreads the heat so much it's very difficult to get it right. And then you need to anneal the piece to get it back to the right strength and hardness. Almost impossible to do outside of a factory environment.

Most truly custom rims are CNC machined from a solid chunk of metal for just this reason...

Jim

I say it depends. I've had a dozen repaired; unles the wheel only costs $125 or less to begin with, try to have it repaired.

I have welded more aluminum rims than I care to remember. They weld just like any other aluminum casting. 4043 filler, no preheat, cover with cardboard for a slow cool. I have never had one come back. With that being said, I would NEVER use one on my personal car.

I probably wouldn't use one on a race car...for the street, not a problem. Of dozens of rims repaired over the last 30 years in the DC/MD/VA area, I've never had one break where it was welded/repaired. That's not to say the same wheel wasn't bent somewhere else and heated/straightened.

Forged wheels..different story, but then again, so few are forged. Hasn't proven to be an issue.

Don't ever describe a KISS concert if you haven't seen it....

Sratching my head here....
 

...What?

Or am I reading into a "Keep It Simple Stupid" cliché that this old (currently lives in Ohio, but formerly) Detroit rocker may of missed in the 70's while dabbling in the substance’s of the times.

The point was conventional wisdom doesn't count if you haven't welded or seen one welded. joshe8695 has it right. The rims weld up just fine, you do have to watch for hydrogen bubbles in the weld, minimize with proper cleaning and shield. Don't have to TIG either, MIG works fine with 4XXX wire (4043 commonly available); I prefer preheat to 200F and let it cool in the oven. Of course, that's if you are refinishing the entire wheel...you want to strip it first. If you're just repairing one leak/crack, sand the area around it the to-be-welded, clean it with acetone and then brush with a stainless steel brush used only on aluminum..if it's a power brush keep the speed down so you don't rub/sweep contaminants into the soft metal.

ER5356 is just too damn strong for most cast aluminum and will tend to crack when it cools. You also use a PUSH rather than drag weld technique (MIG)...if you backhand it chances are you'll get H2 embrittlement from inadequate shield.

Yes, I have done similar alloy welds with a MIG and...
 

..Oxy/Acet with 30% silver for ACR joints with a nitro purge trace (trade related only) and your dead nuts right on the rims.

But all kidding aside what does a "Kiss Concert" have to do with this thread
with all due respect of course.

Jimmy Buffet song.....perhaps eejimm had never seen a KISS concert...or welded a rim.


Manana
By: Jimmy Buffett
1978
She said I can't go back to America soon
So goddamn cold it's gonna snow until June
Yeah, they're freezin' up in Buffalo stuck in their cars
And I'm lyin' here 'neath the sun and the stars

Customs man tells her that she's gotta leave
She's got a plan hidden up her shrewd sleeve
Wants to find her a captain, a man of strong mind
And any direction he blows will be fine

Chorus:
Please don't say manana if you don't mean it
I have heard those words for so very long
Don't try to describe the ocean if you've never seen it
Don't ever forget that you just may wind up being wrong

Tried and I tried but I don't understand
Never seemed to work out the way I had it planned
Hangin' out at a marina when Steve Martin called
Singin' anybody there really want to get small

But women and water are in short supply
There's not enough dope for us all to get high
I hear it gets better, that's what they say
As soon as we sail on to Cane Garden Bay

Chorus:
Please don't say manana if you don't mean it
I have heard your lines for so very long
Don't try to describe the scenery if you've never seen it
Don't ever forget that you just may wind up in my song

-- Spoken: "Alright let's reggae reefers!"

Called all my friends on those cheap nightly rates
Sure was good to talk to the old United States
While the lights of St. Thomas lie twenty miles west
I see General Electric's still doing their best

I got to head this boat south pretty soon
New album's old and I'm fresh out of tunes
But I know that I'll get 'em, I know that they'll come
Through the people and places and Callwood's Rum

Chorus:
So please don't say manana if you don't mean it (don't mean it)
I have done your lines for so very long
Don't try to describe a Kiss concert if you've never seen it
Don't ever forget that you just may wind up being gonged

Coda:
And I hope Anita Bryant never ever does one of my songs
No no no

Very Cool!
 

I Did not Know this...

I had a large crack on the inboard barrel of my 2000 Golf's wheel (a 17" BBS 17x7), and I filled the crack with JB weld. It's got 6,000 very hard miles on it and one flat repair from a nail (tire off and back on is the point), no issues whatsoever. Not to say there won't be, but a 20-minute $2 fix beats the hell out of buying a set of wheels.

Holy Sheet. I would hope you at least drilled the end of the crack to keep it from propagating.....

This is one app for JB Weld I would not have thought of although I have seen various metal-filled epoxies (DEVCON titanium-filled comes to mind for putting CTIS hubs on axle ends of 2 1/2-ton military trucks being reworked to diesel/automatics at AMG in South Bend). Perhaps the steel-filled JB Weld is stronger than the parent aluminum but I doubt it.