Hand Guard Epoxy Nightmare

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[ARCHIVED THREAD] - Hand Guard Epoxy Nightmare

Posted: 9/10/2018 3:40:43 PM EDT

Did a real stupid thing. The epoxy that came with my free float hand-guard, which is supposed to be used to attach the hand guard to the outside of the barrel nut, I went and used instead on the threads of the barrel thinking it was a special lube that came with the barrel nut.

Yeah, it's so stupid it's funny so no offense taken if you want to laugh out loud. The instructions were also pretty clear.

Well now the barrel nut is pretty much welded onto the barrel and I guess it's OK since it is fit properly but it annoys the living heck out me and I want to take it off, clean it and put it back right.

It's too tight to use with the torque wrench and the nut adapter (the adapter just flies right off). Is there some way to loosen that epoxy up so I can unscrew it?

Since I've already admitted to one mistake I guess I should go ahead and mention that I put the hand guard onto the barrel nut using the epoxy as well (yes, even after realizing I made the mistake) so that has to come off first. Not sure if that means the hand guard must be broken off. If so, I could live with that but stripped barrel threads - no. I'll just leave everything alone if that is the case.

Posted: 9/10/2018 3:43:52 PM EDT

[#1]

Heat is only thing that may work.

Posted: 9/10/2018 3:52:04 PM EDT

[#2]

Was it blue or red or green?

Posted: 9/10/2018 3:55:46 PM EDT

[#3]

Shoot it.

Leave it alone.

Posted: 9/10/2018 3:57:52 PM EDT

[#4]

Throw it all away and buy new. Less nerve wracking.

Posted: 9/10/2018 4:00:46 PM EDT

[#5]

As long as it's properly aligned and won't come loose, leave it. Heat will probably work but I'd leave it alone. Live and learn.

Midwest Industries?

Posted: 9/10/2018 4:05:03 PM EDT

[#6]

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Quoted:
As long as it's properly aligned and won't come loose, leave it. Heat will probably work but I'd leave it alone. Live and learn.

Midwest Industries?

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Yes G3 M-SERIES M-LOK FREE FLOAT

Yeah. Leave it alone. How do you remove these hand guards if you must? Don't think I'll ever by any epoxy based parts ever again if I can avoid it.

Posted: 9/10/2018 4:10:50 PM EDT

[#7]

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Quoted:
Was it blue or red or green?

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Green

Posted: 9/10/2018 4:16:07 PM EDT

[#8]

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Quoted:
Green

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Quoted:

Quoted:
Was it blue or red or green?

Green

Green is recommended for locking preassembled fasteners, e.g. electrical connectors and set screws. The product is categorized as medium-to-high-strength for wicking. It is also available in a liquid form, cures in 24 hours and can be removed with heat and hand tools.

Leave it alone though. Really.

Posted: 9/10/2018 4:49:38 PM EDT

[#9]

I agree with the others, if it is aligned and setup correctly just go with it. Green is not hard to remove however. I worked on a PRI tube with red loctite and it gave me fits but the scorpion I did a barrel swap on with whatever euro white stuff they have laughed at heat and my vice but I was determined and got that off eventually.

Posted: 9/10/2018 5:19:39 PM EDT

[#10]

First of all, if you used the included green adhesive then it is not epoxy. It is an adhesive and not all that strong of an adhesive either.
To break it off the barrel nut, reverse the forend clamp screws, insert a thin piece of metal between the forend clamp halves and tighten up the screws against the metal, spreading the clamp halves. Just spread it a little and it will break the bond and the forend can be wiggled off. Not a big deal at all. I am always switching things around and remove the forends after being secured with the green adhesive all the time. This is a stupidly simple task and takes all of two minutes.

As to the barrel nut being bonded on the upper, throw some heat on it and it will come loose.
A heat gun will work but so will a propane torch. Don't go crazy and burn it though, just enough heat until it starts smoking and be ready to unscrew the barrel nut when it does smoke.

Don't make things sound worse than they are. It is just a mild adhesive, like blue Lock-Tite, not some kind of super glue epoxy which can be a bitch to break.

Posted: 9/10/2018 5:25:12 PM EDT

[#11]

Heat and torque in inexperienced hands does not inspire good thoughts.

Posted: 9/10/2018 5:31:41 PM EDT

[#12]

Quote History

Quoted:
To break it off the barrel nut, reverse the forend clamp screws, insert a thin piece of metal between the forend clamp halves and tighten up the screws against the metal, spreading the clamp halves. Just spread it a little and it will break the bond and the forend can be wiggled off.

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To put it back just apply more adhesive? Does the old adhesive need to be cleaned out somehow? Where do I get more?
Thanks

Posted: 9/10/2018 5:50:47 PM EDT

[#13]

We all do stupid stuff, don't be hard on yourself. I personally would leave it unless I planned on selling it someday, then I would either fix it or notify the buyer of the situation.

Posted: 9/10/2018 6:08:03 PM EDT

[#14]

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Quoted:
Heat and torque in inexperienced hands does not inspire good thoughts.

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Leave it, but if you do decide to heat and torque, video it!

Posted: 9/10/2018 6:47:08 PM EDT

[#15]

Leave it. If you can't live with it, trash it out.

Posted: 9/10/2018 8:02:55 PM EDT

[#16]

Assuming they provided a green retaining compound such as Loctite 680 (not threadlocker) if it's for joining the hg to the surface of the barrel nut. If so and you insist on removing it, propane torch it to a solid 250F and bust it loose. Or a good heat gun. Don't use oxy-acetylene. Too hot. If all is well as is, I'd leave it as is.

Posted: 9/10/2018 10:07:33 PM EDT

[#17]

after you break it all down, and go to reassemble the barrel nut, use JB Weld instead.

just kidding! honestly, I don't use the green stuff that MI provides with their rails, because I know that rail's gonna have to come off at least 5 more times before it's all said and done. something like that. the Gen 3 locking tab and the knurling seems to do the job, keeping the rail secured to the barrel nut, probably more that locking tab thingie than the knurling.

Posted: 9/11/2018 10:20:26 AM EDT

[#18]

Quote History

Quoted:

To put it back just apply more adhesive? Does the old adhesive need to be cleaned out somehow? Where do I get more?
Thanks

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I only use a couple of drops total, one on each side of the barrel nut, so I always have lots left over for many applications. If the forend will slide over the old adhesive I just add another drop or two and get on with it. If it has built up to the point the forend will not slide over without some fuss, then I wire brush off the barrel nut and inside the forend, if needed. You do not need to remove every trace of old adhesive and usually only the barrel nut needs a light brushing. I have heard 91% alcohol will remove it but I have not had any luck with that or Acetone removing set adhesive.

Before MI started including the green or blue adhesive with the forends, I used Blue Lock-Tite. It may not be intended to bond the forend to the barrel nut but it does a fine job of doing so. Since it is not specifically designed for that use, it breaks loose easily just like the stuff MI includes with the forend.

Posted: 9/11/2018 10:09:47 PM EDT

[#19]

I have quite a few of the MI G3 hand guards. I don't apply the adhesive and have not had any issue yet.
I'm not extremely hard on my gear but don't purposely take it easy either. Typical use is 3 gun style dynamic shooting and hunting.
Obviously they include the adhesive for a reason but I feel for most users it is overkill.
YMMV

Posted: 9/12/2018 8:16:01 PM EDT

[#20]

With the G3, I cannot comment with absolute certainty since I have never tried the G3 WITHOUT the adhesive, but on the G2, I have had them slip if the adhesive was not applied on the .30 HRT and .458 SOCOM. After using just two drops of adhesive though, no more slipping and with only two drops applied, it is a breezed to break the bond and remove. As I said earlier, I am always finding some reason to tinker with these expensive Lego sets so nothing stays put for long before I find a reason to remove it to change something, even if it is just a muzzle device and I need access to the barrel for using the barrel vice. Even if MI told me it was not necessary to use it, I would on these calibers.

Posted: 9/13/2018 7:23:02 AM EDT

[#21]

No adhesive and close to 8k without issue. If you have the lock plate that prevents the HG from slipping forward you do not need it. Also, look at Loc-tite's site, they have the temp, yield/break strength on there. Green isn't that strong and unless you have the high temp version, no more heat required for any color.

Posted: 9/18/2018 9:28:45 AM EDT

[#22]

Barrel nut, handguard, barrel, etc. all installed properly and functioning fine?

Leave it.

Posted: 9/18/2018 10:15:24 AM EDT

[#23]

just out of curiosity - what brand handguard? Never seen one that used epoxy to help hold it

Posted: 9/18/2018 1:46:36 PM EDT

[#24]

Quoted:

G3 M-SERIES M-LOK FREE FLOAT

.

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Quoted:
just out of curiosity - what brand handguard? Never seen one that used epoxy to help hold it

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Posted: 9/18/2018 2:48:44 PM EDT

[#25]

I would probably leave it alone.

If you want something to worry about, I would ask if the thread locker was already setting up, maybe even hardening before the barrel nut was installed. If it was there might be a possibility it didn't allow a good metal to metal fit between the barrel and the nut. Maybe down the road it melts and the barrel loosens up.

All of that said, if I was going to side eye the weapon all the time worrying about it, maybe even not trusting it, I would surely take it apart and do it right. If I couldn't get enough purchase on the nut because of an inadequate tool I would find a way, any way to grip the nut or destructively remove it and replace the nut.

Posted: 10/2/2018 1:55:06 PM EDT

[#26]

I took it to a gunsmith and had him fix it. The barrel nut wasn't screwed in all the way and couldn't be moved due to the loctite so the barrel was jiggling slightly. He told me he had to use a pipe wrench to get it off after heating it up. It came off without any damage to the barrel nut and he was able to clean it, grease it and get it back on right. Probably could have done it myself but I'm glad I had it checked out.

Posted: 10/2/2018 8:00:33 PM EDT

[#27]

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Quoted:
just out of curiosity - what brand handguard? Never seen one that used epoxy to help hold it

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And you still haven't. It is NOT epoxy that is used, the OP used the wrong word, it is just a bonding agent like Lock-Tite to help keep the forend from slipping on the barrel nut with heavy recoiling rounds. On something like a 5.56, especially with the G3 version, it is likely not even needed, but on something like a .458 SOCOM or .50 B, a little bonding agent will make doubly sure the forend does not slip on the barrel nut.

Actually, I stand corrected, there are forends out there that do use epoxy for the forend/barrel nut interface. I have an old Clark carbon fiber forend that came with something like JBWeld that you mixed and used on the forend to bond it to the barrel nut. The ONLY thing holding that carbon fiber tube to the barrel nut was the epoxy that they supplied, but the MI G3 is nothing like that.

Posted: 10/2/2018 8:39:49 PM EDT

[#28]

First - don't know how I missed this thread.....

No offense to OP, but YAYYYYYYY! I am not the only dumass that used the MI adhesive on my barrel nut! Everything is tight and after about 500 rounds it is a sweet shooting pistol so I am going to leave it as is. When instructions say to read all the instructions first, please read all the instructions first, or join the dumass club

Posted: 10/2/2018 9:31:13 PM EDT

[#29]

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Quoted:
First - don't know how I missed this thread.....

No offense to OP, but YAYYYYYYY! I am not the only dumass that used the MI adhesive on my barrel nut! Everything is tight and after about 500 rounds it is a sweet shooting pistol so I am going to leave it as is. When instructions say to read all the instructions first, please read all the instructions first, or join the dumass club

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Ha ha. I would have left it alone too but I panicked and backed out a little and then couldn’t. This made things worse and left the barrel loose. All good now and I met a great local smith willing to clean up and point out my mistakes.

Posted: 10/2/2018 10:19:26 PM EDT

[#30]

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Quoted:

Quoted:

G3 M-SERIES M-LOK FREE FLOAT

.

Quoted:
just out of curiosity - what brand handguard? Never seen one that used epoxy to help hold it

Midwest Industries but, as Big-Bore pointed out, there was no epoxy involved. It was just green thread lock.

Posted: 10/3/2018 3:14:08 AM EDT

[#31]

You should probably watch this installation video at the end it shows how to release the adhesive.
https://www.youtube.com/watch?time_continue=561&v=ilZdWk9y_Yo

Posted: 10/4/2018 4:54:17 PM EDT

[#32]

Benchrest guys used to glue their actions into the stock.

I'd just leave it be until it comes time to rebarrel.

Posted: 10/6/2018 11:43:31 AM EDT

[#33]

Something epoxy doesn't tolerate well at all (almost all epoxy adhesives) is cold. I don't mean a little cold, I mean like -45 degrees F.
It becomes brittle, shrinks away from what it is adhering to, and loses strength.

I agree with everyone here who says leave it alone and shoot for now.

If in the future you want to take it apart, purchase some dry ice at the local supermarket (the Publix near me carries it) and some methanol (wood alcohol) from the paint store.

Find a metal or ceramic container that isn't overly large, put in your dry ice and then the methanol. The methanol is there to evenly distribute the cold (from a physics perspective it's there to carry away the heat). Put in your receiver (barrel pointing up) and submerge to the level of the barrel nut.
Wait 15 minutes and then remove the barrel nut as normal.

Did I mention that epoxy doesn't tolerate cold?

G.