Does anyone know how to chemically strip annodizing? I've got an A1 upper receiver I want to refinish along with a couple other parts and I don't want use a sand blaster on it.

Anodizing cannot be stripped off with chemical. It is a surface hardening treatment to the aluminum. You might have better lick with steel wool or green scotch bright pads.

most people use an acid of some sort.  phosphoric is popular.

Are you trying to finish it to a different color
Or get a Battle field look

its one of the royal tiger cracked receivers i want to try to fix. and i just want to get it looking like the same color again once im done. the other parts are mag release buttons, delta rings, Charging handles, and a buffer tube i want to refinish to "Colt Grey"

Was not aware of that. Learned something new!

Dont bother stripping it.

Prep for welding
Weld
Grind

Sandblast and shoot it with Norrells.

Make a LYE and Water mixture. It will strip it off.

It reacts highly with aluminum so if you mix it too strong the glass container can get very hot and crack .etc Start with a little lye and add to the mixture.



I dip small aluminum parts in Naval Jelly until the finish is gone.

Naval Jelly works on parkerized parts.  I don't think it has any effect on anodized aluminum parts.

Where can i get the chromic acid and phosphoric acid?

http://www.amazon.com/Phosphoric-Acid-High-Purity-1000ml/dp/B009S05Z2Q

DRANO

but dont keep it in there too long. It can start to eat through the aluminium itself!  Ask me how I know!

Drop an aluminum ar15 trigger guard into it and leave it for an hour, it will strip the anodizing and dye off.



Here is me reanodizing the trigger guard. Notice the bare metal delta ring on the far right and bare metal trigger guard in the container.




 

Is it cheaper to get myself set up to annodize my own parts, or to just have someone else do them. Currently, I have 2 uppers, a buffer tube, 2 delta rings, a charging handle and 2 mag release buttons to do. I do plan on doing an 80% lower or two in the future. How hard is it to set up and do? To get the right color?

Quoted:







Type 2 isn't that hard, nor expensive to do.



The hardest part is keeping the acid bath cool enough ~70 degrees. It's hot in Louisiana so I went out at 2am in the morning to do most of my work. The advanced setups have chillers. I used a small fan to keep the cool night air blowing over my jar. I went with a tall glass jar so that I could put it in the fridge for a few minutes when the wife was asleep.





Now to anodize large things like a receiver you need more amps. Your amp value is dependent on the surface area of the part to be worked on. You would need a large bucket to do a receiver because it will heat up the solution quickly because of the higher amps. A larger volume of bath will help keep the solution cooler for longer but the outside air temperature should also be low to help keep it cool.



Chillers are used on nicer setups to cool. I've also seen some people insulate their buckets to help protect them from warmer ambient air.

Fish tank bubblers are also used by many hobbyiest to keep the acid bath and the dye bath agitated.





Battery Acid from autozone was around $10. A couple of these should do.


The lab power supply I have goes up to 4amps. It was ~$30 on ebay.


The rest of the stuff you might can get around the house. Lye, De-greaser (I like pressurized break cleaner), rubber gloves, lab thermometer that goes up to 200F, large pots, Distilled Water, Baking Soda. Aluminum wire, Aluminum blocks of various surface area.


I think you can get TYPE 2 setup like mine that can anodize a receiver for ~$100. I plan to try this myself eventually.





Here is my home anodized trigger guard and delta ring from the setup I posted above.