ANODIZING- FAILURE TO LAUNCH

[f100rat]

Well I tried my hand at anodizing this last weekend and everything looked good till I got to the dye stage, the receiver would not take any of the black. Everything I read said Rit would work, just not as good as a commercial dye. After one hour in the dye I rinsed it off and it did nothing. The receiver is 6061 alloy, the battery charger was putting out 35 amps for an hour and ten mins, the battery acid was mixed with equal amounts of distilled water, all the connections were good, and everything fizzed.
I really want the receiver anodized as the last two I finished I used Wheeler Engineering ceramic-coat from Midway. It looked really good to start with but in just normal handling it chipped real easy and I'm tired of touching it up with a permanent marker. Any help with the anodizing, or a better home finish would be greatly appreciated.
Thank you to any one with some advice.

[uxo2]

vaderspade i beleive has a
DIY on ar15.com

Or you can ask him

[kcstott]

Your acid mix is a little hot. Correct ratio with pre diluted (ready to use battery acid) is 3-1 bath must never exceed 75 degrees F or your anodize will be very thing and soft.
Rit dye does work just not the black. Buy the stuff from caswell plating it work great nice dark black color.

You'll have to strip, polish degrees and reanodize and dye again once you get the correct dye.
I used to do fishing reels and Rit does work. Blue, Green, Purple, Blood red, all came out great. Black just dulled the finish didn't work at all. Bought the Caswell plating Black dye tried again worked great black as midnight.

[f100rat]

Thanks,
Between kcstott and vaderspade's info I hope it will go better when the dye I ordered comes in. My only concern now is how to decide how long to leave it in the acid bath. Too long sounds like it will hurt the aluminum and too short a time, the dye won't soak in.

[kcstott]

How long is a matter of amps over time based on the surface area of the part.

Here's a calulator720 calc

81.8 square inches = 3.41 amps @ 15 volts for 1 hour to get .0005 thickness.
Remember that anodizing build it's thickness 50% on the surface and 50% below. So a .0005" thickness would equal a .0005" change in part size.

[858casper858]

Damn Kerry, my head hurts! Pfft... This is why I stick with my Ak's.

[kcstott]

Yep parkerizing and rattle caning is way easier then Anodizing. Hell even Cerokoting is easier

Here's the thing I USE TO do anodizing. I wouldn't do it now at gun point. Send that stuff off to someone that does it full time.

[f100rat]

Darn, I might have to take my shoes off to calculate that much!!

[kcstott]

Hey I can count to 21 naked

[Rusty Scabbard]

35 A ? Sounds like a lot current unless it was a big part. For type II, ideal is to run 12A/sq ft. of surface area for 1 hr. Adjust the bath time if the amp density is a little off. Keep temp of the anodize bath 65-70 F and be sure the dye bath isn't over 140 F.

[f100rat]

O.K. I received my com. black dye and had a go of it again this last weekend. I set the battery charger at a lot lower 12 volt setting (6-10 amps), kept the 3 to 1 battery acid to distilled water at about 70 F with water frozen in plastic bottles, changed the lead cathode to aluminum, cleaned my receiver about 20 times, and let it cook for a little over an hour. It came out perfect. If I could take time and figure out how to post pistures I would show it. I tried a small test piece of aluninum in Rit black dye at the same time and it looks just as good. My first time the acid was too strong, the amps was too high and it made the acid bath too hot. Now the only thing I'm not sure of is if the aluminum cathode in stead of lead made a difference. Once you get everything set up it's not a hard thing to do, if you want a finish that seems to last longer. Next week I'm going mix some batches of dark green, brown and tan dyes and try a camo pattern.