Anodizing Question

[boar308]

Do i need to bead blast my 80% lowers before anodizing them? I did one with a type 2 ano, and was not really happy with the results. Please let me know.

[drkphibr]

I guess that depends on the look you are trying to get. If you bead blast before anno, I'd imagine you'll get a powdered or dusted look to the finish vs. a polished or glossy look. Anno is no a coating in the sense it covers any possible blemishes of finish of the material. Anno enhances or magnifies the "grain" of the finish or blemishes.

I would recommend sending your lower to a shop that does paintball gun anno work. You'll LOVE the results and what they can do. If you search pbnation.com, you'll find plenty of examples.

[kcstott]

Exactly
Any anodizing does nothing to cover surface imperfections. What ever finish you start with is what you end up with just high lighted or magnified. Even the grain lines in the polish will stand out.

[VaderSpade]

If you use etch in the process the finish will be about the same as if you bead blast it.
I found bead blasting to be a waste of time.

[Rusty Scabbard]

Are you home anodizing ? Bead blast isn't needed, but absolutely clean parts are. I anodized a couple 6061 TM10-22's and a few unrelated 7075 parts with good results. I used a 3 quart tupperware thing for the ano tank that I found at a thrift store. I also picked up a drink cooler (1/2gal) that made a perfect dye dipping tank, and a few tupperware rinse tanks at the thrift store.
Clean parts well. Degrease with carb or brake cleaner, dry, then wash with 140 F water with a little dish soap. Rinse well, rinse again with distilled water. Don't let anything dry at this point - have the ano bath and rinse pots all set up before you get stuff cleaned and ready to go. Depending on the alloy, you may go straight to anodize, or etch and desmut. 6061 seems to work fine going straight to anodizing after cleaning. My 7075 parts came out better with a short lye etch and desmut step.
Anodize at 12A/sq ft current density for 1 hour in 17% H2SO4 solution. Be sure the anodize bath temp doesn't heat up over 72 F, and keep it well mixed with an air sparger. With small ano baths, the temp will rise. A lot. I put my 3 quart tank in big cooler / water bath, and added ice as needed. After the ano, rinse the part well with distilled water, and rinse it again. Rinse water temp should be around room temp.- hot water can form the hydrate. Then dunk into dye solution at 120 -140 F. Not over 140F. Deep color should be obtained after around 10-15 minutes. Finally, pull parts from the dye and dunk into nickel acetate sealing solution at around 200 F for 20 minutes. It's done ! Hang parts to dry. They'll look chalky. My 7075 parts had a grey haze. But after rubbing with oil, they came out great. The 7075 parts needed to be buffed a little.
If the anodize is screwed up, strip with lye solution and try again. Be careful with the lye solution that the parts don't get etched too bad. It only takes a few minutes to dissolve the anodize layer.
If you're using a battery charger, you won't be able to adjust charge current as easily as an adjustable supply allows. But at 14.4 volts typical of battery chargers, it'll be reasonably close to the target current density of 12A/sq ft as long as the bath temp is 66-70 F and the H2SO4 concentration is around 17 %. If you miss 12A/sq ft, adjust the anodize time accordingly (i.e., if current density is 10A/sq foot, anodize for 72 minutes instead of an hour). I ran the 10-22's at 5.4 Amps for 60-70 minutes.
Wear safety glasses when the chemicals are out. No exceptions. Costco sells big boxes of baking soda that's great for cleaning up spills and neutralizing the acid when you're done.
Good luck ! I did a couple trial pieces, and had to re-do my first 10-22 attempt, but then I got the anodizing to come out great.

[boar308]

thanks for the input. My uncle (who is a machinist) set up an anodizing tank for me. i just thought anodizing would have covered all the imperfections, if i had bead blasted the lower. Im happy with the results, but its not perfect like i imagined. Thank you rusty for taking the time, and giving me a tutorial on the setup process. My uncle spent an afternoon with me at his shop, making sure i knew what was going on. The 10-22 will hit the ano tank on sunday.

[kcstott]

Just be meticulous about being clean. Wash your hands wear clean gloves don't cross contaminate etc.... Any little bit of dust, dirt, grim, or oil in the air will screw up the dye

[goober]

all great advice
my $0.02:
the electrical connection to your part is crucial. it must be good and must not be compromised during the ano process.
+1 to never touching the parts with ungloved hands once its clean
+1 to avoiding cross-contamination by rinsing the part in distilled water between baths
+1 to never letting the parts dry once you've started. the warm part will air dry faster than you think if you let it. keep your rinse container of distilled water (clean) handy at all times that you can drop the part in quickly if you need to for any reason (have to pull the part out of a bath to fix something, slight delay between baths, etc.)

[Gunsmith Dan]

If you want to hide the imperfections paint it or powder coat it. Use epoxy filler made for aluminum, fill all the bad spots, sand it with very fine grit paper, clean it VERY good (nylon scrub brush and acetone) then paint or powder coat.

Also if ypu plan to paint it you can get a aluminum primer, a good primer will not only increase adhesion but also hide alot, not all, of the imperfections

Plating or anodizing will not hide surface imperfections. (unless you want to go through a VERY tedious process of zincating the aluminum, copper plating ....sanding, plating, sanding, plating until all the imperfections are filled in then plate it with a harder metal).