rit dye alone really wont penetrate..it might get a small tint..but thats just from the dye particles getting physically stuck inside the pores in the aluminum, which rub off quickly with use and will usually just stick to
crevices. it might actually look cool like that tho.
i tried this long ago with r/c car parts and rit dye.
one of the hardcore flashlight modders can probably verify if i miss anything.
you need:
rubbermaid bucket(walmart)
car battery charger 2/6/10amp (harbor freight or walmart)
1 gallon sulfuric acid(car battery acid- napa might still carry it-but in 5gallon jugs only?),
3 gallons distilled water(grocery store),
aluminum plate (hobby store definitly/true value/maybe jo ann fabrics)
aluminum wire( home depot/lowes)
rit dye(grocery store)
make a 3:1 solution of distilled water and sulfuric acid in your bucket.. enough to cover your light. pour the water in FIRST, and then slowly add the
acid..(never in reverse, as it will boil the acid quickly).
connect the negative wire of charger to the aluminum plate and dip the plate in the water-secure it to the side of the bucket. also dont let the clamp/copper negative wire touch the water/acid bath.
attach positive wire of charger to aluminum wire - bend and slip it through the flaslight body. hang it into the solution and do not allow it to touch the aluminum plate from the previous step. again only allow aluminum metal to
touch the bath.
i would start the charger at 2amp for a small flashlight and if you dont start
to see bubbles forming on your peice/plate then bump it to 6 or 10amps..
heat will form in the water..you want to keep it somewhat cool(as heat will seal the anodizing). so take some water bottles which have been frozen and put one or two in the bucket while the process is going.
i would say about 90 minutes would sufficiently build up a decent anodizing surface on the light. while it's in the bath..the flashlight should get a dull grey-yellowish tint to it. once that tint is uniform on the entire flashlight..take it out. if you leave it in too long, the anodizing surface can
become rough.
and while the part is nearing completion in the acid bath......
make a pot of water and put your rit dye in it and heat it up to 100 degrees..no hotter!
and heat up another pan with boiling distilled water....
when the part is done in the anodigzin bath, rinse it with COLD water
and drop it into the 100 degree rit dye bath for 15 minutes.
then drop the part into boiling water for a few minutes
let it cool and dry..enjoy.
EDIT: just picked up a 1 Liter/32oz container of sulfuric acid at autozone.
it was only $4. i'll mess with it later in the week.
