[Amc-list] POLISHING STAINLESS - ALUMINUM - was - Re: '65 Classic Headli
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[Amc-list] POLISHING STAINLESS - ALUMINUM - was - Re: '65 Classic Headlight Rings - [ http://grassrootsmotorsports.com/images/bill/FitandTrim.pdf ]



Message: 11
Date: Mon, 29 Oct 2007 20:51:44 -0700 (PDT)
From: d stohler <das24rules@xxxxxxxxx>
Subject: [Amc-list] 65 classic headlight rings
To: amc-list@xxxxxxxxxxxx
Message-ID: <983641.97598.qm@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
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ok, so how do i tell if they are anodized aluminum or stainless???

dave stohler
http://picasaweb.google.com/das24rules





===============================================================




http://grassrootsmotorsports.com/images/bill/FitandTrim.pdf




dave: If it is Stainless Steel - it isn't Anodized -
download the above .pdf for a Read: 

here's some Quote:



Grassroots Motorsports 113


Is It Chrome, Aluminum or Stainless?
When talking about modern-era cars, there are three common
bright trim finishes: chrome, anodized aluminum and stainless
Older American cars tend to use chrome-plated steel for
their shiny trim. This provides perhaps the shiniest silver finish
available. The process involves sanding, polishing, and buffing
the steel, which is finished with three plating processes: copper,
nickel and finally chrome. It is a labor-intensive process involving
corrosive chemicals, and can be quite expensive.
In the old days, before the EPA, every city had plating houses
that would plate anything. Today, the industry is regulated, and
most platers only want to hang big parts like bumpers. Most of
the ones that will do small parts charge way too much. Few, if
any, will quote you a price over the phone. They want to see
the work.


If you have lots of parts to plate, do-it-yourself kits from
companies like Caswell, Inc., present an alternative to sending
your parts out to a plating house. The initial investment to get
into triple-chrome plate production at home is between $450 and
$650, plus polishing and buffing supplies. This is a bit steep for
most of us, but if you can get your friends or local car club to go
in together on the kit, you can save big time.
Many older European imports use aluminum trim which is first
polished, then anodized, and finally color buffed. Since the final
brightness is a surface buff, this shine will dull over time; repeated
polishing or buffing eventually wears out the anodizing, leaving
you with plain, dull, oxidized aluminum. This polish-anodizecolor
buff process is not very common today.


Most modern aluminum trim is just anodized, resulting in a
tough, but not very shiny, finish. While it is true that aluminum
can be chrome-plated for a very high shine, many plating shops
stay away from aluminum.
Dale Watson of Colors, Inc., provides advice here. "There is
a modern alternative that will give your aluminum a very shiny
and long lasting finish," he explains. "We pioneered this finish
several years ago just for applications like auto trim.



It is called
'bright dip anodizing.'"



Fit & Trim How to Make Your Car's Brightwork
Look New Again
story by pete dubler . photos by camrenne dubler
Once the trim pieces have been removed from the car,
the old finish needs to be removed. A professional shop
can easily handle this job, but the do-it-yourselfer can
achieve good results by carefully sanding away the old
finish. A drill press can make this job easier.
Once the major problem areas have been handled, wet
sanding will be next. For optimal results, start with
rough, 220-grit paper and work all the way through
2000-grit. In theory, you'll spend the most time with
the coarser papers.
Grassroots Motorsports 114
When most of us think of anodizing, we
tend to think of colored finishes like the red
or blue used on Aeroquip-type hose fittings
or the black of modern anodized trim. Dale
explains that anodizing is first clear, but
can be changed to any color. "Anodizing is
actually the process of growing aluminum
oxide crystals on the surface of unoxidized
aluminum."
The process begins with a cleaning of
the parts to get the aluminum really shiny
and chrome-like, Dale explains, followed
by a bath in a special bright-dip solution
that brings up the shine.
"After bright dipping comes the anodize
process, which is a bath of sulfuric acid
with DC current," he continues. "This bath
puts on an oxide coating in varying degrees
of thickness based on time in bath and
temperature of solution. If dyes are added
during this stage, the aluminum will take
on color, any color, even patterns of colors,
such as camouflage. Or, if no color is required, then the parts are
sealed to close the pores of the oxide coating."
Dale explains that when his company is dealing with car restoration
parts, about 95 percent of them are sealed after anodizing
for a bright, chrome-like finish. "Sealing is an absolute must due
to the open pores that result after anodizing which will absorb anything
that comes in contact with the part, even fingerprints."
The finish is tough when complete. Even though it's only
about 3/10,000 of an inch thick, the hardness is right up there
with a diamond.
Anodizers are a dime-a-dozen, but very few will do small
batches and even fewer do bright-dip anodizing, which is the
process you want for your aluminum. For example, bright-dip
anodizing a full set of trim off a Porsche 914 costs about $110
plus shipping. This is a minimum lot charge, so most sports cars'
trim sets should cost in the $75 to $125 range. The key is to get
as much as possible done at once to lower the cost per part.
There are two other alternative treatments for aluminum. First,
you could just polish the metal, and keep polishing it periodically
with an off-the-shelf aluminum polish like Mothers. This
typically results in a higher luster initially, but dulls quickly
between polishings.
A final alternative is to polish the aluminum, clean it, and
then have it clear powder coated. This finish is durable---but not
quite as durable as anodizing---and may cost as much as or more
than bright anodizing. Since it is slightly shinier, it will not quite
match the original finish. Still, clear powder coating is a popular
alternative worth considering.
The third type of bright trim is stainless steel, popular on older
American and British cars since it's both shiny and durable. Its
strength makes it a good choice for long, thin pieces like body
side moldings. When picturing stainless steel trim, think of the
side pieces on a '57 Chevy or early MGB. How to tell stainless
steel from chrome? Stainless looks a little less shiny than chrome,
and like aluminum, it is non-magnetic.

Unlike chrome-plated steel and anodized aluminum, stainless
steel receives no separate surface treatment.

Stainless is an alloyed
metal, which is typically harder and resists rusting and pitting.

While it holds up well to daily abuse, removing dents and dings
can take a lot of grunt work thanks to the material's strength.

Making stainless bright and shiny is just a matter of polishing,
though it will never be quite as shiny as chrome-plated steel.

Regardless of the final finish---chrome, anodizing, bright dip
anodizing, clear powder coating---or the material---steel, stainless
steel, or aluminum---the preparation, which any hobbyist can do,
is virtually identical.

In fact, for stainless trim, the "preparation"
is the final finish.

Actually, there is a fourth option for automotive brightwork:
chrome-plated plastic. More common on newer cars, chromeplated
plastic can turn white over time. Restoring this trim is
usually not an option, so new pieces must be found.

First Do No Harm

Twenty years of hitting bugs at highway speeds can really wear
on windshield trim. Thousands of ons and offs of a targa top will
wear grooves in the rollbar trim. A little battery acid or acid rain
might even wear through the anodizing or chrome around the engine
compartment. The only solution is to remove the old finish, sand
down the base metal, and prep it for a new final finish.

The first step is to remove the trim without damaging it.
Standard
trim removal tools go a long way in this department, but experience
goes even further.

Don't just start pulling!

Research how each piece of trim is attached to the car's body.
Most trim is just held on with snap-on clips of one sort or another,
but surprises lurk under the most expensive pieces of trim.

For The aluminum will get shinier each step of the way. From
left to right, we have pieces of aluminum trim after different
steps in the process: 2000-grit sandpaper, Emery,
Tripoli, White Diamond and rouge.
After wet sanding, the aluminum will be polished with
our four different compounds---Emery, Tripoli, White
Diamond and rouge---each one finer than the next. Periodically
rinsing the piece will reveal any problem areas
that still need attention.



-- 

    =Bt=
milnersXcoupe
"The Heretic"


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