Anodizing Q

[going_home]

Why does real light colored anodizing seem to rub off when dark colors dont seem to do that ?

I always liked black or dark colored anodizing, seemed to hold up good.

Picked up a 2012 marker recently, very light, almost opaque color.

When I got it I was disappointed, the color is worn down to the bare metal on the asa and barrel.

:(

[athomas]

It might be coincidence that your aluminum products with the lighter finish were not sealed as aggressively. This could result in a surface that wears faster and lets the color wear off.

[BigEvil]

I think that is more of a coincidence Allen. You probably have just run into some sub par anno work.

[GEE TEE]

Are you sure it's actually worn off or just faded?

Some pigments used in annodising dye process aren't very UV stable and fade or discolour fast when exposed to sunlight

[Spider-TW]

There is a possibility but it is not common on commercial jobs. The ano temperature and rate affect the pore size and hardness of the layer at the same time. Good current and cold gets toward the hard, type III ano process with small pores. Long low current and warmer makes a softer layer that may have pores so big that the dye washes out in the sealer. The actual dye color doesn't affect the hardness, but some dyes will be able to work in larger or smaller pore sizes by either sticking in large pores or penetrating small ones.

Once you wear the seal layer off the top, the open pores can loose the dye, especially from larger pores.

[luke]

What these guys said.
The actual anodizing of the aluminum has nothing to do with the color. Color is just a dye in the annoed layer.

[going_home]

I expected Bob Longs stuff to hold up better than this.


:(

[Spider-TW]

Some dyes fade in the sun badly. New dyes seem to get released without much testing sometimes. Other than that, caustic chemicals and the baking craze are about the worst things for ano and ano dye. If it's a recent BL, you might contact them about it. They have a pretty good service reputation.