Where to have a lower anodized?

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[ARCHIVED THREAD] - Where to have a lower anodized?

Posted: 5/7/2005 8:14:34 PM EDT

I don't think my lower is particularly well anodized. I'd like to have it redone. What FFL does this?
Class III anodizing to much to hope for?

Approximate cost??

Posted: 5/7/2005 8:44:14 PM EDT

[#1]

Here are two:

Tech Plate $125, approximately a two week turnaround.

P. C. of Titusville $145, approximately a two week turnaround.

Posted: 5/7/2005 8:58:45 PM EDT

[#2]

Good night! I had no idea anodizing was so expensive....

Paul

Posted: 5/7/2005 9:06:46 PM EDT

[#3]

PC is higly recommended

Posted: 5/8/2005 3:59:44 AM EDT

[#4]

I believe P.C. is the company that anodizes for Bushmaster as well.

Posted: 5/8/2005 5:23:21 AM EDT

[#5]

Alternative to annodizing.

www.pre-ban.com/forums/index.php?showtopic=19024

Posted: 5/8/2005 6:40:42 AM EDT

[#6]

Quoted:
Good night! I had no idea anodizing was so expensive....

Paul

In other words, it's cheaper to buy a new lower; unless the piece you have is some sort of collector's item. Or, you can use a paint type finish, and either do it yourself or have it done for about $40-$50.

Posted: 5/8/2005 6:54:28 AM EDT

[#7]

I just refinished with molyresin, I was surprised that it is easy to get good results - as long as you degrease very well.

Posted: 5/8/2005 11:37:52 AM EDT

[#8]

Indeed a Stag arms, or even a Fulton lower would be cheaper...

The part does have serious sentimental value, however. Tremendous sentimental value.

So.... does the moly resin protect the aluminum as well as anodizing? If so, I'd go that way in a second. I have an airbrush, compressor and oven. And I'm home during the day 2X a week when my wife is at work, free to smell up the house... :)

Posted: 5/8/2005 4:40:00 PM EDT

[#9]

Quoted:
Indeed a Stag arms, or even a Fulton lower would be cheaper...

The part does have serious sentimental value, however. Tremendous sentimental value.

So.... does the moly resin protect the aluminum as well as anodizing? If so, I'd go that way in a second. I have an airbrush, compressor and oven. And I'm home during the day 2X a week when my wife is at work, free to smell up the house... :)

Adonizing is expensive if you only have one piece done. New-arguy and four of his friends got together and had their preban purple Bushies done by PC and it came out to $75 each shipped. Norrell's molyresin will protect the adonizing. I did a Colt lower 2-1/2 years ago and it still looks great. I did six thin coats total, baking between coats and it has held up very well. An 8oz bottle of Norrells will go a long way. BTW, the smell is not that bad. I had no problems with my wife. I did a lower, a bunch of uppers and mags. Just keep the windows open.

Posted: 5/8/2005 4:57:17 PM EDT

[#10]

Ever look at the Brownells Baked on laquer? I don't know if it will stick to non-ferrous metal, but since its baked on maybe it will stick to anything that will take the 350 deg cure.

Posted: 5/8/2005 6:59:50 PM EDT

[#11]

Here is an old A1 upper I refinished with Molyresin. This is the "Flat Black Socom" color. Note the exact match with the new DPMS lower I stuck on there for comparison.

This is not a mere paint, it is very tough. Anything that would scratch it would also scratch the original anodizing.

Posted: 5/10/2005 12:23:46 AM EDT

[#12]

Anodize it yourself!
this, this, and especially THIS are good.

Posted: 5/10/2005 8:32:16 AM EDT

[#13]

Heard of folks doing it at home with a car battery, water, and acid.

Posted: 5/10/2005 5:14:51 PM EDT

[#14]

Are you required to do a class 3 hardcoat or is it possible to get a regular anno job on an upper receiver??

Posted: 5/10/2005 5:27:47 PM EDT

[#15]

Quoted:
Heard of folks doing it at home with a car battery, water, and acid.

I have done it. I anodized an 80% lower and then gunkoted it for color. Assuming you have a battery charger you can do it for about $50 in materials, but you will still need to paint the lower once you are done. And find a place that accepts battery acid. And not receive chemical burns in the process. I managed to pull all of those off.

Do not confuse anodizing with painting. Anodizing is a way to harden the surface of aluminum, while coatings simply give it a nice color. If you construct an 80% and only paint it you will quickly have the holes egg out and porbably have the buffer tube come flying out at some point.

Although industrial processes allow for coloring during the Anodizing process, it is essentially impossible for the average guy at home to color a lower with the Anodizing process.

Posted: 5/10/2005 6:14:24 PM EDT

[#16]

Quoted:
Are you required to do a class 3 hardcoat or is it possible to get a regular anno job on an upper receiver??

I've had discussions with people who really know anodizing and they seem pretty confident that a thick class 2 coat is nearly as durable as a standard class 3 coat. I believe thickness of coat is a product of time in the bath, but don't quote me on that.

Posted: 5/10/2005 10:29:03 PM EDT

[#17]

I fear misinformation may have been spread:

1) MILSPEC AR's are *not*, to the best of my knowledge, Hardcoat Type III anodized. Type III anodizing is VERY hard, requires extraordinary control over voltage & tank temperature, and hence is usually un-dyed as it's difficult to do. That's why T-III anodizing is almost always seen in an olive-ish or "natural" color. Think Surefire flashlights, which are all T-III anodized.

Type II black-dyed anodizing is plenty hard, and it's the customary AR finish. Open your Yellow Pages and you'll find plating shops local to you that have the capability.

EDIT: Disclaimer: I don't know if an FFL is required for someone to do this work to your lower. I'm no legal expert.....and I'm not advising anything here. Just pointing out a few things.

/TCP

Posted: 5/10/2005 11:33:01 PM EDT

[#18]

Quoted:
it is essentially impossible for the average guy at home to color a lower with the Anodizing process.

Ahem, did you read any of the links I posted? It is NOT "essentially impossible!" to add color, it is a simple step.

Posted: 5/11/2005 3:51:51 AM EDT

[#19]

Quoted:
Quoted:
it is essentially impossible for the average guy at home to color a lower with the Anodizing process.
Ahem, did you read any of the links I posted? It is NOT "essentially impossible!" to add color, it is a simple step.

That's not class 3 hardcoat, though. When you step up in classes of hardcoat, it gets harder and harder to add color, except for maybe black. There is a big difference between the links you added and milspec class 3 hardcoat. Class 3 is done at or near 40F and at a much higher voltage than your standard run-of-the-mill anodizing, both of which are hurdles that make it very hard to properly anodize a receiver in your home.

Posted: 5/12/2005 9:26:37 AM EDT

[#20]

.

Posted: 5/12/2005 10:02:20 AM EDT

[#21]

Quoted:
That's not class 3 hardcoat, though. When you step up in classes of hardcoat, it gets harder and harder to add color, except for maybe black. There is a big difference between the links you added and milspec class 3 hardcoat. Class 3 is done at or near 40F and at a much higher voltage than your standard run-of-the-mill anodizing, both of which are hurdles that make it very hard to properly anodize a receiver in your home.

Interesting, I did not know that about anodizing, thanks.

40F, that's a bit on the cool side. (the following is just me thinking into the keyboard) Anyway, one should be able to conjure up highish voltage even at reasonable current simply by taking a variac, output bridge rectifier, and a bank of caps. It would not the the cleanest DC ever, but it should get the job done. With this, you could get upwards of 120volts. Come to think of it, you could probably get away without the caps, and just live with the pulsed DC out of the bridge rectifier.

I see why the high voltage is necessary, as the metal anodizes, the resistance will go up, and you need more voltage to punch through the coating to add more.

Posted: 5/12/2005 10:29:58 AM EDT

[#22]

Can someone define what "higher voltage" is necessary for a class 3 anodizing job?

40F is nothing, why is that such a concern? I can find a used refridgerator or freezer for $100.

Posted: 5/12/2005 5:20:54 PM EDT

[#23]

Actually, Type-III is much more than just low temperature. It requires 50-80amps/sq ft (low voltage though 15-25v). The higher current produces a lot of heat, which requires a circulatory pump to eliminate the heat build up around the part being anodized, and it requires a chiller that will maintain the temperature between 28-38F. The circulation pump also eliminates the bubbles that are produced. The bubbles have a tendency to 'stick' to the part being anodized which cause the area under the bubble not to anodize. On some dyed items, this will show itself as pinpoint sized white spots. It also requires a higher concentration of sulfuric acid.

Posted: 5/12/2005 7:06:46 PM EDT

[#24]

Quoted:
Actually, Type-III is much more than just low temperature. It requires 50-80amps/sq ft (low voltage though 15-25v). The higher current produces a lot of heat, which requires a circulatory pump to eliminate the heat build up around the part being anodized, and it requires a chiller that will maintain the temperature between 28-38F. The circulation pump also eliminates the bubbles that are produced. The bubbles have a tendency to 'stick' to the part being anodized which cause the area under the bubble not to anodize. On some dyed items, this will show itself as pinpoint sized white spots. It also requires a higher concentration of sulfuric acid.

Yep, here's the anodizing reference I was talking about. I'm a damn knuckle dragging mechanic - voltage/current - it's all the same to me.

Posted: 5/12/2005 9:17:49 PM EDT

[#25]

Quoted:
I fear misinformation may have been spread:

1) MILSPEC AR's are *not*, to the best of my knowledge, Hardcoat Type III anodized. Type III anodizing is VERY hard, requires extraordinary control over voltage & tank temperature, and hence is usually un-dyed as it's difficult to do. That's why T-III anodizing is almost always seen in an olive-ish or "natural" color. Think Surefire flashlights, which are all T-III anodized.

Type II black-dyed anodizing is plenty hard, and it's the customary AR finish. Open your Yellow Pages and you'll find plating shops local to you that have the capability.

EDIT: Disclaimer: I don't know if an FFL is required for someone to do this work to your lower. I'm no legal expert.....and I'm not advising anything here. Just pointing out a few things.

/TCP

Tech Plate and PC of Titusville and many others that anodize weapons have FFLs as required by law.

Posted: 5/13/2005 2:23:21 AM EDT

[#26]

Do it yourself! Battery Charger, battery acid, hydrometer (battery acid tester), cheap hot plate, thermometer, plastic pail, stainless sauce pan from the flea market and optional color dye.

I like Ron Neuman's page for the step-by-step. I have anodized two lowers and several other items myself.
http://www.focuser.com/atm/anodize/anodize99.html
Hard anodize isn't all that great. It is about as important as having "Colt" magazines. The hard is just a skin backed up by soft aluminum. Good for large bearing surfaces, but won't prevent dents and nicks. Plain old home anodizing isn't as hard, but it isn't soft either.
Regards, Ray

PS: You will have to strip the old anodizing first. Ron's page tells how to do it with lye.

Posted: 5/13/2005 6:21:05 PM EDT

[#27]

There are 4 benefits for anodizing.
1) Put a harder surface on soft aluminum as ray-vin points out.
2) Provide corrosion protection.
3) Increased lubricity of the surface.
4) Increased wear-resistance.

To be technically correct, there is absolutely no difference in 'hardness' between Type-II, Type-III, "Hardcoat" or "Mil-Spec" anodizing. Aluminum oxide is aluminum oxide is aluminum oxide and is the same 'hardness' no matter what you call it as long as it is properly grown. The difference between them is the thickness of the coating and the density of the anodic cells. Neither of these factors increase the hardness of the surface or increase the corrosion resistance. They DO increase the wear-resistance and lubricity of the coating.

Applied coatings such as Norrell's, Durakote are and all the others are excellent in providing benefits #2, 3 & 4, but they are no where as hard as an anodized surface and will suffer wear damage and hole enlargement much faster than a similar part that is anodized (although this may not be evident until 50,000-100,000+ rounds or more). If you are planning or expect your lower/upper to see hard service, then there is no substitute for anodizing.

The perfect finish would be an anodized coating of 1-2mils thickness along with Norrell's, Durakote, etc. applied over it. This would give you all the benefits of both and none of the individual shortcomings.

Posted: 5/13/2005 6:37:34 PM EDT

[#28]

The anodizing info in this thread has been instructive for me, I will have to ~~try~~ do it sometime on some of these Al things I have laying around. I do have that regulated 40v/40a powersupply laying around... could be useful hty.gif

Once the holes enlarge, all one would have to do is enlarge the holes slightly more, mill a small rim on the inside of the lower and add some sort of hard metal insert that will fit in the larger hole, being stopped from passing through by the rim in the lower, and provide a hole of the appropriate size at the appropriate location for whatever was there in the first place.

I would assume that this is illegal, since nearly everything is, but still might be interesting to do if it is legal.. but probably cheaper to just get a new lower. Might be able to send it back to the mfgr and get a new one with (replacement, they keep the old one) the same SN. Wait, that might be illegal too....

Posted: 5/14/2005 9:55:48 AM EDT

[#29]

A 40a/40v power supply is perfect, as long as it will work in constant current mode. For a lower (about .6 sq/ft), anodized at 6amps/sq ft, it only requires 3.6amps constant current if using a 3:1 mix of water to battery acid. Voltage will peak about 12-15vdc. To get a 1mil thickness, it will require 2hrs of anodizing.

You may not have to worry about using inserts or bushings on the holes. If there isn't any excessive wear, and the lower hasn't already been stripped twice before, it shouldn't be an issue.

Posted: 5/14/2005 10:14:31 AM EDT

[#30]

TAG

Posted: 5/14/2005 12:56:06 PM EDT

[#31]

Quoted:
A 40a/40v power supply is perfect, as long as it will work in constant current mode. For a lower (about .6 sq/ft), anodized at 6amps/sq ft, it only requires 3.6amps constant current if using a 3:1 mix of water to battery acid. Voltage will peak about 12-15vdc. To get a 1mil thickness, it will require 2hrs of anodizing. (snip)

Yea, it will do constant current. It is kind of fun to hook a thin copper wire across the outputs, crank the voltage to max, then turn the current up until the copper starts to glow. When I get around to anodizing something, I will keep this in mind, thanks.

Posted: 5/19/2005 3:43:44 PM EDT

[#32]

The reason I suggested the Norrell's to the original poster, his lower is already anodized, and that should not be removed. So he has all the surface hardening. I assume he is just dissatisfied with uneven color in the anodized surface.

Do NOT confuse color with anodizing. An aluminum part may be well anodized, but the color not even. Happens all the time. I sell anodized aluminum products. Some are the natural aluminum color. They ARE anodized, just not COLOR ANODIZED.

Anodizing leaves the surface porous so that a dye may be added and color the surface. This is done after the acid bath. Then the final step is a sealant, to seal in the color.

If it is only color, or eveness of color, he does not need to strip and reanodized. He can do the Norrell's himself, with minimal equipment. The hardness of the surface is already there.

[ARCHIVED THREAD] - Where to have a lower anodized?

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