Author Topic: 57 Brougham - Chrome plating Aluminium bumpers?  (Read 1473 times)

Offline Ross Morgan #22943

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57 Brougham - Chrome plating Aluminium bumpers?
« on: May 07, 2009, 04:55:47 AM »
I'm looking at casting the rear bumpers on a '57 Brougham (mine are very pitted) and one of the materials the foundry can use is aluminium. Does anyone know if there are difficulties in choming this metal and it lasting?  I will ask the local plating shop but I wanted to get some feedback from the forum.  Thanks!  Ross.

Offline Otto Skorzeny

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  • 1956 Coupe de Ville aka Bismarck
Re: 57 Brougham - Chrome plating Aluminium bumpers?
« Reply #1 on: May 07, 2009, 10:16:44 AM »
Use the search function above on this forum to find a recent lengthy discussion on the subject. A couple vendors were listed. It's a complex and expensive process.
fward

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Offline Ross Morgan #22943

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Re: 57 Brougham - Chrome plating Aluminium bumpers?
« Reply #2 on: May 07, 2009, 07:57:02 PM »
  For some reason, I was thinking the bumpers were an aluminium alloy but reading the thread http://www.cadillaclasalleclub.org/forum/index.php/topic,104460.0.html   , it appears that they are aluminium.  Good news though that with careful selection of a plater, chrome plating aluminium can be done with long term success.  Regards, Ross.

Offline Walter Youshock

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Re: 57 Brougham - Chrome plating Aluminium bumpers?
« Reply #3 on: May 07, 2009, 08:08:08 PM »
They were sand-cast aluminum, as were the wheels.  Saber wheels and the bumper ends on '55-'58 Eldorados were also like that.

The plating process is very different.  Decent originals in the hands of an inexperienced platers will melt in the wrong solutions.
CLC #11959 (Life)
1957 Coupe deVille
1991 Brougham

Offline Whit Otis, 1188

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Re: 57 Brougham - Chrome plating Aluminium bumpers?
« Reply #4 on: May 07, 2009, 09:16:56 PM »
I believe the wheels were forged light alloy, not a casting, in order to have the strength to endure the lateral stress that wheels experience on turns.  Also, I forget for sure, but the center hub was not a light alloy forging.... anyone know for sure?
Whit Otis
Whit Otis - 1941 6219D Custom; 1941 6219D: 1940 7533F; 1948 6069X; 1985 Eldorado Biarritz
Drawing of AP Sloan Custom by Terry Wenger

Offline Mike Josephic CLC #3877

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Re: 57 Brougham - Chrome plating Aluminium bumpers?
« Reply #5 on: May 07, 2009, 11:06:38 PM »
These were hybrid units.

The outer part of the wheel was an aluminum alloy (once piece including the center hub)
that was riveted to a steel inner wheel.  That's how all of the sabres were made starting in
1955 until the end of production.  The riveting process changed, the dimensions of the inner
steel wheel also changed (starting in 1957) to accomodate larger brakes. Kelsey
Hayes made them for Cadillac with technology from Alcoa for the aluminum issues.

I have a few spares in my basement and 5 restored ones in my 1955 Eldorado. 
BTW, they can be replated nicely by somebody who knows what they are doing.
Recommendation:  Valley Wire Wheel in California.  They are expensive ($1,000 per
wheel) but you will not regret it.  I had mine done 3 years ago and not a sign of a
pit, flaking chrome or any other problem.  Yes, they hold air well even with tubeless
tires as they should (they were designed for that).

Mike
1955 Cadillac Eldorado
1973 Cadillac Eldorado
1995 Cadillac Seville
2004 Escalade
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Past: VP International Affiliates, Museum Board Director, President / Director Pittsburgh Region

Offline Peter Nieuwlandt

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Re: 57 Brougham - Chrome plating Aluminium bumpers?
« Reply #6 on: May 08, 2009, 02:26:13 PM »
Of course Mike is rigth on the Sabres .These wheels consist of 2 parts and are rivited together.
I've found that not many people know how to disassemble and reassemble the Sabres,but the Porsche guys can help You out because the 911 model uses exactly the same type wheels .

Peter
Peter Nieuwlandt
CLC 17863