Blackening Aluminum

Hi all,

Does anyone have a reasonably simple recipe for blackening aluminum?
The simpler the better, household or hardware store chemicals would
be ideal.

Cheers & thanks
Hans Durstling
Moncton, Canada

G’day Hans; This isn’t a recipe but a suggestion; simply anodize the
aluminium and dye it with household dyes.

Immerse the workpiece in a vessel containing pickle or sodium
sulphate solution, (sold as Glaubers Salts in a pharmacy), to act as
an electrolyte. Connect the work to the positive lead of about 6-12
volts direct current (batteries) and a piece of stainless steel to
the negative, stir occasionally Leave it for half an hour (you can
experiment with scrap aluminium) wash and then use a dye - black -
in your case obtainable from most supermarkets, or even pharmacies.
Wash the work well in hot water and dry properly. The dye should not
wash off or rub off easily, because it is attached to the thin film
of alluminium oxide produced by aluminium.

Cheers for now,
John Burgess; @John_Burgess2 of Mapua, Nelson NZ

Hi Hans,

Try Aluminum Black Metal Finish made by Birchwood Casey, Product

I used this to blacken some aluminum parts on one of my.45 caliber
Colts, which is what it is designed for.

Wayne Emery

Hi Hans,

I like Birchwood Casey (maker) Aluminum Black. It will give aluminum
a matt dark black finish. If you want it glossy spray a non
yellowing polyurethane on the piece. Once it’s dry you can take it a
step further and wax it.

Birchwood Casey is used by gunsmiths to blacken alum parts on guns.
It can be purchased at a gun or sporting goods store.


Rather than pasting the links, I’ll just tell you - I just googled
“blackening aluminum”, and the first two links were just what you
want - probably further, too.