Aluminum Mold Anodizing?

[bdbruce]

Working here in the Silicon Valley at a Semiconductor Company, I read and see many "High Tech" things. Also being new to this forum, I was wondering has anyone ever tried getting a aluminum mold block clear hard anodized. I know you can specify the thickness of the anodizing. I believe anodizing is a process that both reduces and adds to the dimensions of the mold. (the surface of the metal is converted to aluminum oxide). If your mold can tolerate some slight dimensional change, would it help in appearance or the ability of the boolits to fall out of the mold easier. make the mold more durable?

Now I wonder if I should of searched for previous threads regarding this Post, again I'm a newbee.
Getting even crazier, sprayed ceramic coatings?

Big Daddy Bruce

[geargnasher]

I've done it, there's a thread here somewhere where the things you mentioned about thickness, etc. were discussed. I added about 1.5 thousandths to the thickness, but the mould I used was oversized for my intended use, as I wanted to go .457 down to .453 or so, it worked like a champ and I wish that all aluminum moulds were anodized.

http://i1328.photobucket.com/albums/w538/Geargnasher/thum_89094feba647d7c48_zpsf551ca6e.jpg (http://s1328.photobucket.com/user/Geargnasher/media/thum_89094feba647d7c48_zpsf551ca6e.jpg.html)

Gear

[btroj]

Would anodizing reduce galling? Prevent lead from adhering to the mould?

What sort of cost is involved?

[geargnasher]

Anodizing eliminates the galling and sticking almost completely. The oxide is really, REALLY hard, it will blunt a TiN-coated drill bit. The biggest challenge to doing the coating is removing every single piece of non-aluminum from the mould. On some of the offerings from the custom manufacturers, it would be tough to remove the alignment pins and such without damaging them. This old two-banger Lee mould was a cinch, though.

Something I did that needs to be taken into consideration was I removed just over a thousandth from each block face before doing the coating so the resulting bullets would still be ROUND after the coating was applied, albeit smaller in diameter.

Gear

[btroj]

So it is best done as part of the manufacturing process.

[MtGun44]

Yes, although it is not particularly complex to do. Basically, apply electric
power to the mold while submerged in cooled sulfuric acid solution, then boil
in fresh water to finish the process. Color will depend on thickness and alloy.
It is porous and will absorb dyes, this is why most anodized parts are colored.
Surface is aluminum oxide.
This is what is done to AR-15 uppers and lowers to make them "black" and to
harden them for wear resistance.

Bill

[dkf]

Most anodizing shops will charge a minimum. The shop I use for type III hardcoat has a $95 minimum. Keep in mind that all anodizing is not the same. Type III hardcoat is about the hardest and thickest you are going to get and requires specialized equipment to do.

[frnkeore]

I've only done Mil-Surp anodizing and the standard thickness is .0002. I could build up parts by at least double that but, I don't remember what the max build up was for it.

I checked into a commerial anodizer here for doing some gun related stuff and their min is $80 for a batch. It's not so bad if you have a lot of molds to do or someone to go in with you. The batch size is very large, about 2 ft x 4 ft.

Frank