[alt-photo] Re: odd tintype observation

[Christina Anderson]

John, I've been scouring! WIth a heavy duty scour brush. But, come to think of it, I haven't used my trusty Scotch Brite scouring pad that I use for gum so you reminded me! Out with the arsenal.

I was going to have to take out the steel wool but didn't want to mess up the metal plates.

Etienne, it is definitely as you say, below, anodized, then, not painted. I wouldn't know my aluminum from my silver even if my father was a metallurgist...
Chris

Christina Z. Anderson
christinaZanderson.com

On Nov 23, 2010, at 3:38 AM, John Brewer wrote:

> Just use a scourer Chris. Every gummist has a scourer in their arsenal don't
> they?
> 
> J.
> 
> On 23 November 2010 05:13, etienne garbaux <photographeur at nerdshack.com>wrote:
> 
>> Christina wrote:
>> 
>> I got the trophy metal plates (black painted aluminum) from a trophy store
>>> 
>> 
>> I can't comment about the particular plates you got, but aluminum engraving
>> plates are generally anodized (anodizing is an electrolytic oxidizing
>> process).  The oxide layer is dyed black (or yellow, blue, red, etc.).  It
>> is a bonded (not applied) finish.  It is almost always given a hydrophobic
>> sealing as the last process step, to improve environmental resistance.
>> Before it is sealed, anodizing is quite porous and holds many kinds of
>> coatings well.
>> 
>> Best regards,
>> 
>> etienne