Acraglass question

[Brother_Love]

It has been many moons since I used Acraglass. Now there is a Acraglass gel which I am not familiar with. It sounds like it would prevent runs but is it as good?

Opinions welcome! Thanks

 

[RBHarter]

The used some aero space glass balloons , aka bead rods , vs glass fiber in it so it forms and stays sort of put .
Based on description and adds .

In aviation it is used extensively in formed finish areas for strength and fill while saving weight . The balloons that is . The resin is the latest version of acro-glass .

 

[RicinYakima]

Having known Harvey Anderson, who "invented" Acraglass, here my experience. The original 1/10 hardener to base was good stuff when mixed with powdered fiberglass, but was only good for about 40 years before it crumbles. The "gel" is the same chemistry except it is thicker and the build in filler is close to nylon and so far has indefinite life span. But it is not hard, will wear if you take the action out often and sometimes does not re-bond well for repairs. The same chemistry is used with both powder aluminum and steel and sold under different trade names. The advantage of the ones sold for stock making is that if the action sticks, you can put it in the freezer overnight and will usually break out the next morning.

Devco and JB weld use a little different chemistry, are less forgiving but stronger.

Acraglass gel is trouble free for beginners, and strong enough for any reasonable gunsmithing chores.

 

[Chris]

Acraglass is very easy to work with, does not run as much. What Ric said. My first choice for bedding.

 

[Ian]

It's ok if you don't mind crumbling it out every 20 or so years and re-doing it. Had two fail so far, one using the original and one using the gel. Very frustrating that the bedding won't last the life of the rifle.

Been using Devcon liquid steel and Marine Tex grey for about a decade now and have had no failures so far....time will tell.

 

[Pistolero]

Wow. I Acraglassed my R77 in about 1977 and it is still perfect, looks and feels like the
day I finished it. Used it on a couple of other rifles, only about 10-12 yrs on them, hope they
hold on.

I wonder if they changed the formula after I did my old Ruger?

Bill

 

[RicinYakima]

Two things with Acraglass: it is temperature sensitive when you mix it and use it, and it is humidity sensitive when you mix it. It really only has a range of about 65 to 85 degrees and that includes curing temperature. Only failure I had was a batch I mixed at 100+ degrees and less than 10% humidity. When I took it out the next afternoon, it all crumbled like brown sugar. When all else fails, read the directions.

 

[Ian]

My rifles have seen a lot of temp swings over the years, particularly heat. I'm sure the humidity was high enough when mixed, temperatures were for sure out of range (it's Texas, 65-85 is a 15 minute swing range here) so both factors probably contributed to the degradation of the epoxy over time. I've installed a couple of barrel liners using AcraGlas and chilled it per Brownell's instructions for longer pot life, so far so good, so I'm not sure the lower temperature limit for bedding cures is entirely accurate, or may be only a recommendation for bedding actions due to tolerances and not necessarily a lower limit for the chemicals to work properly. Nothing cures correctly in high heat, not paint, not urethane, not even cyanoacrylates.

The stuff is ok and I've used a lot of it for little jobs, but lean toward the others I mentioned for everything now except for skimming in scope bases, which is a job for red Loctite.

 

[fiver]

I have used the regular stuff with good results.
I don't have the weather issues Ian does.
65-70 is just the indoor temperature, and humidity in the 30% area is common.
50% is comment worthy in town.

 

[Intheshop]

Smooth On EA 40 is a staple epoxy in bow building.It's magic in rifle bedding because it damps and soaks up vibrations.Been around for well,ever.Taint cheap,but the good stuff rarely is?We use it on some pretty serious wood engineering efforts as well....where there can't be mistakes.

Don't use it for everything,so it's not like some snakeoil nonsense.And got to be a safety nazi here....uncured and to a slightly less degree,cured epoxy should be treated with the utmost respect towards personal safety.Gloves and positive air flow.Be especially aware of grinding("sanding") the stuff.