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Discussion Starter · #1 ·
My first ever ak was a cheap wasr 10 and its been my project gun ever since I bought it. What Im doing is adding shims inside the mag area made of black delrin and I need some help with adhesive choice. Ive cut them to size and plan on drilling shallow holes to accept the adhesive but Im not sure which to use. Does JB weld have the strength to take friction from magazines being rocked into place?

Some might see this as a stupid project but I need something to do till my CMP garand gets here lol.
 

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Why are you adding shims? mag-wobble??? JB weld would be worth a try, I think the only thing that might get to it after time is oil...and it might break loose. Might not ever come loose...try it.
 

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Discussion Starter · #3 ·
The mag wobble sucks in it. I got spoiled since I built my polish underfolder and figured I had time and $5. Another thing I came up with was to notch the shim so it fits over the section of the lower rail that is SUPPOSED to stabilize the magazine. Im experimenting here in my head and havn't tried it in the rifle, so if it interferes with the bolt Ill just scrap that idea. Thanks 555th
 

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You got the right idea, I wish I had more details, but a shooting buddy did something like this but had metal shims welded in. You shouldn't need ones the go all the way to the rails but try to go the length of the mag well.
Sorry can't suggest an adhesive.
 

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I've never done it ,but how about a couple dedicated mags that have a thin layer of sheet metal spotwelded on? Might also be easier to inspect and repair if they loosen up.
 

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Why not spot weld metal pieces, or tap for a couple of screws. Screws installed from the inside and countersunk could be ground flush on the outside, and with some lacquer putty and paint you'd never know they were present.
 

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I think you will find it is very hard to get glue to stick to Delrin. Might help some if your shallow holes were wider at the bottom than at the entrance to add some mechanical resistance to "pull out" in addition to the glue bond.



From the Wiki:

"Bonding
Acetal polymers are typically very difficult to bond. Special processes and treatments have been developed to improve bonding of acetal. Typically these processes involve surface etching, flame treatment or mechanical abrasion. Typical etching processes involve chromic acid at elevated temperatures. DuPont has a patented process for treating acetal homopolymer called satinizing which creates anchor points on the surface, giving an adhesive something to grab. There are also processes involving oxygen plasma and corona discharge[4].

Once the surface is prepared, a number of adhesives can be used for bonding. These include epoxies, polyurethanes, and cyanoacrylates. Epoxies have shown 150-500 psi shear strength on mechanically abraded surfaces and 500-1000 psi on chemically treated surfaces. Cyanoacrylates are useful for bonding to metal, leather, rubber and other plastics.

Solvent welding is typically unsuccessful on acetal polymers, due to the excellent solvent resistance of acetal. Thermal welding through various methods has been used successfully on both homopolymer and copolymer."
 

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Happy Camper
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You should spot weld some metal plates into place. Delrin, if you can actually get adhesive to stick to it, will wear down on you. But I doubt you'd get that far.

Look here to see a factory metal shim weld job on a Russian RPK:

http://www.aa-ok.com/kr.htm
 

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Discussion Starter · #10 ·
Id like to weld some shims in because it sounds like a better idea. Ill wait till next year when I get the time to use some better finish than the grill paint I have on it now. Would I be able to weld through the existing shims, new shim, and receiver without blowing out one layer of metal? Ive never done any welding with my spot welder so Im pretty clueless with it.
 

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I'd get some sheet steel and build it up to the thickness you're shooting for on the receiver, and practice spot welding those sheets.

If you look at the pictures hcpookie provided, the factory RPK shims are made from bent metal - doubled over where the shim is needed yet a single thickness where spot-welded. That's spot welding has a maximum thickness, that varies by design of each spot welding machine, and works best on relatively thin sheets of steel, no more than TWO sheets thick.
 

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I'd go with JB weld to make sure they work, and also try a Yugo mag, all my yugos are thicker than normal, as well as BG waffles.

Once the JB holds up and it works, then I'd consider welding it.
 
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