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AK build - heat treating your receiver with vodka (picture fat)

Boris

Son of Kalashnikov
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God created Man
Colt made them equal
Kalashnikov made some more equal than others



Warning: using this method will guarantee that your receiver will deform like Russian letter Я, so when that happens, do not run to uncle Boris, crying that your hands grow from your ass and you can not make a simple thing done good. Already, I disappoint in you.

Do not worry, if the receiver will be warped, it will not affect your shooting accuracy, just buy another magazine or two. Have a shot of vodka, it will look straight, have another and you will have two receivers. Listen, you are not worthy to lick the sweat off Michael Kalashnikov’s underpants, so do not try this to impress your devochka.

I read many articles on internet about how to correctly heat treat your AK receiver. Some say that they are made by bearded ladies in Romania and so you can do it in your mother’s basement. Some say that it can only be done by professional “experts” with more degrees from MIT than my mother-in-law anal thermometer. I tell you the truth: they are both wrong! I don’t care how many diplomas you bought from my buddy Vlad. You can not take 4130 and forge it into samurai sword, hard as comrade Stalin will, supple as Natasha’s …. never mind.

4130 is not the most expensive steel with limited range for heat treatment. Having a heat treating oven and plenty of experience would go long, but then you would not be making an AK from scratch.

Another note. I see this picture when people heat-treat only holes instead of all receiver. What is this crap? You are too lazy? Do you also not wipe your entire buttocks after Mexican feast?


OK, let's see the receiver that I'm about to destroy:

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Heat treating ovens and proper tools in general are very expensive. I had to scrounge my milsurp heap for something tubular. Any resemblance to distilling equipment is purely coincidental. Basically, you need something to contain the flame. This thingy actually has refractory lined inside, which makes it more useful.

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Next I insert Chinese weed burner. They are $20 at HF, when on sale.

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It is useful to practice ... a lot. Technically, you need to let your work piece soak in atmosphere controlled furnace, for a while to relieve the stresses of bending. Of course you used some s****y jig to bend it, so your receiver is already f****d. These pictures were taken in a bright sun, so you don't see the flame. It would still take out your arm hair and eyebrows. It has to be neutral at very least, but slightly reducing at best. Otherwise you'll burn out your s****y receiver, or worse, it will become so thin that it won't be able to support anything and you won't know it until the gas piston is trying to find your only brain cell in your skull.

Ok, this is a practice piece of sheet metal to get a hang of flames etc. Do it, it helps.

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Heer, I prepare a quenching solution. I start with pure Baikal water ...

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and then I add first secret ingridient

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then second

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... and now I need to drink more beer

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The rest is simple, heat the receiver and quench it. Do it fast and even. Then stare in the bucket, smoking trying to figure out who is the ugly comrade who lives in the bucket.

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Receiver has gained its soul!

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The next step is to temper the receiver and rails. You need very least 400F. Most kitchen ovens go 450 - 500. Do that. A few hours, throw in some potatoes to celebrate later.

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Ok, I know some comrades like science and want talk Brinell hardness but no one has the tester. Here is a quick way to check the hardness using a spring loaded center punch. Brinell, Rockwell ... f***k 'em.

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I took the punch and made a single mark on my heat treated receiver, a demiled RomyG receiver, part of RomyG receiver that was quenched but not tempered etc.

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The next step requires a microscope. I read the web and people come up with crazy contraptions it is not amusing. I took one webcam and pull the guts out. Did nothing to it. It's just easier to hold it close to the piece. I also used a small part of a magnet wire to compare dimensions of the impact dimple to a constant dimension.

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Here is the spare 4130 receiver flat (annealed), so if you only bend your receiver that's how soft it is:

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This is a piece of RomyG receiver that was quenched to full hardness and was never annealed (it would still not shatter to million pieces like some tool steel)

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This is an original RomyG receiver destroyed per ATF:

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This is part of a RomyG receiver that came with the kit and that I demilled:

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and finally, this is my receiver completely heat treated:

mine.jpg


it's pretty damn close to original RomyG receivers, i.e. almost full hardness with enough tempering. I don't think that you need to go beyond 500F to temper the receiver.


Well, here is the receiver, ready to be painted

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it looks bad ass just as it is

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oh, yeah, here is the secret ingredients for the quenching solution:

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... and Vodka? You drink it.
 
You are killing me with your posts. [smile] I had read the samauri sword effect of heat treating too. Couple of questions. Why didn't you attach the rails before heat treating? Why not using oil to quench over water? Are you going to sandblast before painting? Why food coloring in the water? Have heard to add salt and dish detergent if you use water. Also read to temper at 700 degrees.

Your use of the of web can to verify hardness is incredable. Hats off!

I see you have more than one AK project lined up.[wink]
 
Why didn't you attach the rails before heat treating?

I am really paranoid of warping and with this part dimensions it's really pushing it. Without rails, part thickness is even everywhere. I never tried it with rails, I don't know how it may turn out. My other thought was that all weld joints will be annealed (when I weld them), so if there is a hit on the rails, the joints will yield enough until the force is evenly distributed over all joints. Otherwise, most stress may be placed on just one joint, mostly, so if the rail hit hard it will give (rather than yield) out and other joints will follow like dominoes.

Why not using oil to quench over water?

I did a lot of research and 4130 is pretty common steel (also one of the cheapest). Old timers (when they mention I Love Lucy, you know that they are old) recommend that oil is used for large, thick parts, where uneven cooling is a huge issue. For sheet metal, I heard that plain water based quench is just fine. Actually, one guy posted a link to an Aero-manufacturer that heat treats 4130 1mm sheet metal in water based quench, so how can I argue with that? I got all kinds of oils, it's not a cost issue, but if plain water works best ...

Are you going to sandblast before painting? Why food coloring in the water? Have heard to add salt and dish detergent if you use water. Also read to temper at 700 degrees.

Yes, I think beadblasting is what people do, but I just got plain sandblaster. DuraBake is arriving on Wednesday. I was trying to duplicate the color of p*ss then berate the first person who is going to think that it really was. I suck when it comes to mixing colors. I heard about salt and dish detergent. I don't know why it's needed, well, at least detergent would change the surface tension, so that may work. ... OK, I'll admit it, I was too f****ing lazy to go inside and get the ingredients.

My oven only goes to 450, otherwise, I'd definitely gone higher. I looked at charts for tempering of 4130. It's range is not very dramatic. The difference between 500 and 700 is something like 5 Rockwell points and somewhat of a decrease in tensile strength. There was another paper that said something like toughness decreases after 500 but then picks up around 700-800. I think that's totally open for debate, but I was very curious about the temper of the original RomyG receivers, and looking them, I think that they were not tempered very high.


I see you have more than one AK project lined up.[wink]
be vawy, vawy quiet!!! Wife thinks it's a bunch of tools, but I had to order another barrel pin and end up getting an underfolder to ... you know, just to fill the box. [wink]
 
this is just awesome. outstanding work!

you are funny as hell, boris.


Comrade Flintoid, if not for your insane antics of building AKs in an apartment, I'd never started this and so far, this has been one of the most enjoyed projects I had in a really long time. Thanks man! Keep on rocking in the Free World!
 
My oven only goes to 450, otherwise, I'd definitely gone higher. I looked at charts for tempering of 4130. It's range is not very dramatic. The difference between 500 and 700 is something like 5 Rockwell points and somewhat of a decrease in tensile strength. There was another paper that said something like toughness decreases after 500 but then picks up around 700-800.

Is the oven self cleaning? The self cleaning cycle on my oven jacks the heat up to something like 800 degrees.....

From my HTC EVO via Tapatalk
 
I am really paranoid of warping and with this part dimensions it's really pushing it. Without rails, part thickness is even everywhere. I never tried it with rails, I don't know how it may turn out. My other thought was that all weld joints will be annealed (when I weld them), so if there is a hit on the rails, the joints will yield enough until the force is evenly distributed over all joints. Otherwise, most stress may be placed on just one joint, mostly, so if the rail hit hard it will give (rather than yield) out and other joints will follow like dominoes.

Erring on the side of caution for your first build is wise. There is so much info you don't know what is best. Don't think the weld joints would be effected by the heat treating process. Doubt the originals were done seperately. I don't think putting the rails on before heat treating would significantly increase the mass enough to cause any issues.



I did a lot of research and 4130 is pretty common steel (also one of the cheapest). Old timers (when they mention I Love Lucy, you know that they are old) recommend that oil is used for large, thick parts, where uneven cooling is a huge issue. For sheet metal, I heard that plain water based quench is just fine. Actually, one guy posted a link to an Aero-manufacturer that heat treats 4130 1mm sheet metal in water based quench, so how can I argue with that? I got all kinds of oils, it's not a cost issue, but if plain water works best ...

I think salt increases the density and therefore quenches more evenly. You are right about the dish soap.


Yes, I think beadblasting is what people do, but I just got plain sandblaster. DuraBake is arriving on Wednesday. I was trying to duplicate the color of p*ss then berate the first person who is going to think that it really was. I suck when it comes to mixing colors. I heard about salt and dish detergent. I don't know why it's needed, well, at least detergent would change the surface tension, so that may work. ... OK, I'll admit it, I was too f****ing lazy to go inside and get the ingredients.

You might want to park or black oxide before paint.[grin] Urine would contain salt and therefore be good for the heat treating process.[smile]

My oven only goes to 450, otherwise, I'd definitely gone higher. I looked at charts for tempering of 4130. It's range is not very dramatic. The difference between 500 and 700 is something like 5 Rockwell points and somewhat of a decrease in tensile strength. There was another paper that said something like toughness decreases after 500 but then picks up around 700-800. I think that's totally open for debate, but I was very curious about the temper of the original RomyG receivers, and looking them, I think that they were not tempered very high.

I doubt there was any love from the factories. They were made to be disposible. We just need to learn how to put the love back into them and improve their longevity. I have read there isn't much mass with the receiver so not much time is required to normalize the tempering.


be vawy, vawy quiet!!! Wife thinks it's a bunch of tools, but I had to order another barrel pin and end up getting an underfolder to ... you know, just to fill the box. [wink]
Your secret is safe with me. Mine gave up on me long, long ago.[laugh] What kind of UF?
 
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This thread is awesome!
Boris you are the man
I have a digitally controlled heat treating furnace, with specific heat treating oils and access to a hardness tester if you ever want to go about it that way.

Keep up the good work
 
Comrade Flintoid, if not for your insane antics of building AKs in an apartment, I'd never started this and so far, this has been one of the most enjoyed projects I had in a really long time. Thanks man! Keep on rocking in the Free World!

You're doing a hell of a better job than I ever have. I have yet to bend my own AK receiver and you're doing it with self-cast parts from molten aluminum. If I ever tried that I'd end up burning my hand that wasn't holding the adult beverage off.
 
As others have said I really enjoy your posts. I find myself wishing that you updated them more often. Some of it is funny stuff. O yah... I would love to see your garage/ mill surp pile. I don't throw anything out I think I can use again. I believe if I can find way to do it myself I will but man you come up with some smart stuff. I don't know you at all but am scared to even think about what goes on in your head. Lol
 
akma, I got Polish UF, I'm not touching that thing. The last build was more addictive than crack Rogaine or meth or both at the same time. Also, salt raises the boiling point of water, but it takes a lot of salt, so I'm still not sure about that quench. Vapor bubble formation would prevent uniform quenching over large surface.

Michael, thank you for your kind offer! I have not seen other than an industrial, ball-method hardness tester. What are you using? I will build a small heat treating oven for the next receiver. Backyard heat treating is a crap shoot without proper tools if at all.
 
Props to you. Only a руссиан would use piss to cool metal but be smart about it.
 
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