Gunsmithing Loctite 620

[longrange454]

How can you get loctite 620 to release? It got in the threads on the barrel nut. I'm not overly confident about using a torch. 650 degrees seems like alot of heat around the face of the upper receiver. Thought about CAREFULLY splitting the barrel nut, and getting a replacement.

 

[Ravenworks]

Heat gun and solvent from Loctite.

 

[carlsbad]

Heat to 400 deg or so. Loctite's weakness is heat. the temperature needed to release loctite does not affect steel or even anneal brass.

Heat with a torch. I'd use MAPP gas. You're going to need a lot of heat for the large parts. heat evenly from 2 or 3 directions. You should smell the loctite release and see a little smoke if it can escape. I'm guessing you got in in through the scope mount hole, remove that first and you'll smell the loctite.

 

[Wannashootit]

TDS lists 250° C - 482° F- as the disassembly temp.

https://tdsna.henkel.com/NA/UT/HNAUTTDS.nsf/web/F5D77816C464A255882571870000D857/$File/620-EN.pdf

Color charts (online) or accurate IR temp gun will get you there. 500° F is far from "danger zone"/recrystallization temp. As mentioned, heat gun will get you there as will propane/MAP torch.

Keep in mind that even if you were to precisely slot the nut right up to the top of the barrel thread crests, I don 't see that as being any better - you'll still have the barrel nut "glued" to the barrel, and the slot you cut isn't going to aid in removal; the adhesive isn't going to release without heat.

JMO, YMMV

 

[longrange454]

I was worried about annealing the receiver, BUT i got it. Put the barrel in the vise muzzle up, sprayed Choke and Carb cleaner into the seam between barrel nut and barrel. Let it work for about an hour. Put steady torque on it for about a minute or less and it came loose. For the amount of 620 that set between the barrel and receiver i can't see how bedding is beneficial. It a FN upper/ lower and BHW barrel