275 GTB Campagnola Wheel Alloy Question

I own and am restoring 275 GTB 08669 and am getting near completion- probably Christmas 2009. 08669 originally was delivered from the factory with Campagnolas and the wheels have a few rim chips that need to be rewelded. My restorer,who has a tig welder and has experience welding Mangesium, asked me what the magnesium alloy composition of the wheel is so he could get the correct welding rods. Any help would be appreciated.

 

Campagnolo wheels (not Campagnola), were made in a magnesium-aluminium alloy named Elektron.
Elektron was, and still is, a registered trademark of Magnesium Elektron Limited.
Try to click this website to get some datasheet and information about this issue:
http://www.magnesium-elektron.com/markets-applications.asp?ID=7

Ciao
Andrea

 

Nice link Andrea!
thank you
Craig

 

If the repairs are unduly expensive, those wheels are relativley plentiful; they were used on 330GTC/GTS and 275 GTS as well as longnose 2 cams and 4 cams. The sraight ear knockoffs that are correct for those wheels are somewhat scarce.

 

Andrea
Do you know if Daytona Cromodora Wheels where made of the same material?
Grant

 

I'm using AZ61A, and it has "good coloring" (near-perfect match) to the 308 and BBS wheels I've repaired (rim nicks/scrapes).

Furthermore, it is available from The Welding Warehouse, Inc., in one pound (1 Lb.) packages. Most places have a ten pound (10 Lb.) minimum (at $92.00/Lb.).

Please note that one pound (1 Lb.) of Magnesuim (1/16" x 39") is A LOT of rod!

The Welding Warehouse Inc. : 1-800-800-1150

 

Thanks everyone for the input. Magnesium Elektron in England advised me that the Alloy used during that time period for the Campagnolo wheels was AZ91 and the correct welding rod was either AZ91E or AZ101. A call to Welding Warehouse as suggested completed the deal.

 

John

Can you suggest some sources? I have looked hard for a set of wheels for my 330 GTC and most available are worse than my own, which are suitable for restoration.

Does anyone have any thoughts on the use of these 40 year old mags? On this side of the pond many wheel people won't touch old mags, citing porosity and concerns about structural failure. As far as i know, no one has made replicas although I did read that the original wooden molds are somewhere in Italy.

John

 

Personally I worry about the safety of some older mag wheels and have recast the ones for my P 3/4, 412P, and Dino Competizione.

These days you simply need a wheel to pattern. The cost all in is about 12K USD and you have as many as you need for about 2K each. The new ones look exactly the same and are much better. They also are tubeless and have the safety groove to lock down the bead.

 

The porousness of the alloy casting has always been there, addressed by the detailed painting process of the Technical Bulletin, but as Jim notes to run 'b@lls out' it should be examined CAREFULLY and OFTEN for signs of cracking, at the edges and the steel mounting inserts at the lug bolts....

But in my dozens of wheels, on three 1976 - 77 cars I have yet to "condemn" one....

But then, I just putter around town like a Grandpa......

There HAS been a 330GTC totally destroyed (well heavily damaged anyway) when a wheel let go from the lug bolts, so it's a valid concern on the V12s, I'd think....that wheel shattered in a spectacular manner....
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+1
Several of us in the Dino zone were silently scared when John Corbani developed cracks in his 25+ year old Gottis.

What material did you select to have the wheels made from?
Thanks

 

One recommended by the Wheel mfg. as being safe. Some sort of aluminium alloy. The wheels seem pretty light.

 

Good choise! Best wishes, Kare

 

RF wheel failure at 40 MPH.
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I think the deteriation comments above are valid, and a change to wires may be in order. I do have 16 mags (10 275/330, 6 Daytona) that appear good, but were taken of in favor of Borranis.

If you go with mags I siggest Eddy Wave, X Ray or Magnaflux testing, whichever is suitable before use

 

I have Borrani's in place too, but keeping them clean in our climate is a real bind!

Thanks for the tips about testing.

John

 

AKA Tecnomagnesio Not an easy task to say the least. You should have them tested before the rubber hits the road. In addition if you are going to paint them they will need to be prepped properly. Baked but not too high, primed and painted soon after so no moisture is trapped.

 

Jim,

That's some excellent advice there about the humps for tubeless tyres.

Too many people fit tubeless tyres on wheels that are not suitable for them, with the desasterous consequences when the tyres are laterally loaded and the tyres just give way.

If memory serves me right, the wheels suitable for tubeless applications have an H2 suffix on them, but that is general and not Ferrari related. Anyway, it is easily seen when the tyres are off.

 

That's the one..thanks.....interesting pattern of the failure crack, hard to say if it started at the square holes and travelled across the bolt mounting circle, or the other way around from a failed insert or over tourqued wheel bolt, I tell my guys "easy", on the air guns!

 

I was sent PM on the Ferrari Technical Bulletin for painting the castings..

It's printed out in my books at home..

Do any of you recall the post? Tom S. put it up, IIRC..

 

I'd just buy another set of modern but similar looking mags (hate wire wheels on anything but a proper vintage car, ie. 1930's) and keep the real wheels in the shed.

When you drift into a corner in your post-vintage Ferrari, I'm sure witnesses to this great event are not thinking "heck those wheels are not correct for that car" ... they are too busy clapping and cheering.
Pete

 

As it turns out, I have 8 Campagnolo wheels that came with my 275 gtb (08669). - 4 on the car, 1 spare in the rear. I now realize (but did not realize when he wheels were mounted on the car) , I have 2 6.5X14 and 3 7X14 so I can only assume that the 2 6.5 X 14s were mounted on he front. Has anyone ever heard of or seen this configuration on a 275 GTB long nose twin cam- 6.5X 14 on the front and 7 X 14 on the rears?

Were the 6.5 X 14s used on other cars?

What is correct for the spare for a 275 GTB long nose- 6.5X 14 or 7 X 14?

 

Roelofs in the Netherlands has reproduction 15" Campagnolo design wheel in 7X15 front and 7.5 X 15 rear. The also sell the splined hub inserts. I do not know the price nor do I know anything about them.

 

So what would you put on a 250TR etc???

 

wheels should be

4 of the same size wheels on the car (on the ground)

early car four 6.5 x 14 with a 6.5 x 14 as a spare
late (most) car four 7.0 x 14 with a 6.5 x 14 as a spare