View Full Version : Bedding epoxy alternatives
October 19, 2007, 11:13 AM
What different types of epoxy have you guys used? I am currently out and was hoping to find something local so I can bed a new stock this weekend.
October 19, 2007, 11:49 AM
JB Weld makes a good bedding material. I don't care for the quick cure but the regular JB Weld works pretty good.
I also re-did an old boat last year and have since done several guns in the real fiberglass matt or cloth. It is by far the easiest to use and makes the neatest job.
I just did a Marlin 56 this week in a combo of both. The wood was so hollow from the factory that I damed things up and poured areas in the front and rear of the stock full of JB Weld and then drilled it and pillar bedded it and put real glass around the reciever and under the first couple of inches of the bbl.
The real glass can be cut to fit and laid in to where you want it and the resin brushed into it and the action set in like you would with epoxy.
It is by far now my favorite.
October 19, 2007, 12:37 PM
The standard for bedding materials is AcraGlas, sold by Brownells. It cures hard and can be sanded, filed, cut, or drilled. It is impervious to any solvents normally used around guns, plus several others I can think of that I know have been used on it. It is easy to use, very forgiving, and can be patched or cut out and replaced if you make a mistake. It can be thinned and used as a stock finish, can be used to repair stocks, and can be used to make small parts. All other bedding materials are eventually compared to AcraGlas, and most come up short. Best of all, you can generally find it at your local sporting goods store or gun shop.
October 19, 2007, 06:43 PM
You are really better to wait for some Brownell's Acra-glass.
It's the best.
With that said, in a pinch I've used hardware store 1 hour epoxy.
The trick to getting the most from 5 minute and 1 hour epoxies if to get an exact 50/50 mix, and to mix it thoroughly.
On the 1 hour stuff, I'll mix for 5 minutes.
Try to keep from forming air bubbles in the mix, since this weakens the strength and hardness.
When curing, put the stock in a warm place.
A really good mix, and warmth make for a tougher finished product.
October 19, 2007, 07:46 PM
I've used JB Weld and/or MarineTex boat hull repair epoxy (gray) a number of times with good results.
There is nothing harder than properly mixed and cured JB Weld, but it gives you little room for error. Espcially the version that cures in four minutes.
October 19, 2007, 09:39 PM
Best stuff i ever used was Micro Bed, stuff is awesome:)
October 20, 2007, 02:30 PM
Brownells Steel Bed is probably the best from the standpoint of withstanding repeated battering, as in match shooting. The % steel in the filler is much higher than in JB Weld or Devcon Plastic Steel. The 5-minute epoxies all have much lower tensile strength than the slow cure epoxies, so I would not be sanguine about their durability without some careful testing. Nor, given the heat evolved in the fast cure mixes, would I be comfortable assuming it has the same ability to hold shape against the metal being bedded. Same with polyester-based fiberglass. Especially not if the gun is doing both summer and winter weather duty. A well-filled, slow cure epoxy will exhibit very little change in size as it cures and will remain strong to pretty low temperatures. You may get away with less, especially if you only put a few tens of rounds through the gun each year, but you are better guaranteed good results if you get the right stuff.
By the way, there is a school that feels the rigidity of epoxy bedding is both too unforgiving of wood stock changes with humidity and a little too able to transfer recoil shock. A hard bedded rifle does punch you a little more sharply than a wood stock without bedding. One solution has been to go to a rubber-like bedding material. Devcon Flexane 80 is the most common one. It has a durometer hardness of 80, so it is pliant, but still contacts the gun the same way each shot and still prevents if from shifting in its stock, the main goals for bedding. Just an idea for you to play with.
October 20, 2007, 04:07 PM
The advantage I see to using the Acraglas, is that they give you a release agent to put on the metal parts so they don't stick to the epoxy! And it is colored to hopefully match the stock more or less in case any shows.
October 20, 2007, 04:18 PM
I like the Acra Glass Gel from Brownell's. It's thicker and easier to use. The kit comes with everything and will do plenty of guns as well as other bonding chores around the shop.
October 23, 2007, 02:53 AM
Your local ACE will have the Devcon Plastic steel. It works well and is easy to mix. The steel bed looks tempting. but it's several times the cost....
October 23, 2007, 03:15 PM
The short cure time epoxies are less waterproof as the cure time decreases.
There are any number of epoxy vendors out there, some with all sorts of nice filler materials (like aluminum dust).
Epoxy itself is very thin stuff without thickeners or fillers added.
September 1, 2008, 08:09 AM
I used what is called kitty hair bondo it is fiberglass reinforst just wollow out the stock about 1/16" and dont krank the screws down all the way when it is setting up spray oil on the metal so it dont stick it leaves a mirror finish
September 1, 2008, 08:59 AM
Automotive fiberglass. It's hard and non sandable tho. IMHO Bondo is too soft. Not sure how it would hold up under recoil.
September 1, 2008, 02:09 PM
LongRifles, that is some fine work there!
September 1, 2008, 05:28 PM
In my experience
If you want a general use quantity epoxy,the West systems marine epoxy can be had in a qt can with a small can of catylist.There are fast and slow catylists,and a fairly inexpensive ratio pump is available to put in the cans.
They have a series of additives,from lightweight microbaloon filler to flock,wood flour,etc.Some thin this down for stock filler,but I lack experience with that.They build airplanes and silboats,etc with this stuff.
If you don't have much experience and want a good product that is forgiving and easy to work with(relatively) I like accraglas Gel.It does not run or drip.
While it is true an accraglas kit is expensive,it gives you what you need,the research and guesswork has been done,and Brownell's IS an outfit we want to give our business to.The stuff works!
Regular accra glass is still flowing when you use it.That is good,for fill and penetration.If you are just learning,it can make you sad to see the resin running out the bottom and gaps forming up top.
Steelbed I used in a Hi-tec specialties stock.It adds a little weight,but it was a 30-338.I'm happy.
Polyester(general auto fiberglas) is OK when it is the original matrix in a boat or something,but it does not stick as well as epoxy.Epoxy is what you want.
NEVER mix epoxy and polyester components.Very bad reactions occur.
That ACE hardware epoxy putty that comes in a stick is pretty darn handy stuff!
Devcon titanium is interesting.I used some once in another application.It seems to have a very high solids content,and "stacks" a bit.
I have used quite a bit of flexane to build fixtures ,etc.It is about like a deadblow hammer.It is available in 94 duro.You likely will have some bubbles with it.It does not evacuate in a vacuum chamber well.Haven't used it in a firearm.It really sticks!!
h,and my compliments to the pix,flawless,Beautiful!!I love the box of media!!Walnut hulls?
September 2, 2008, 12:22 PM
+1 on LongRifles Devcon products. They are by far the best. More High Power match rifles such as Garands and M1A'a are bedded with it.
With bedding compund one thing that alot of people forget to consider is toughness.
Having a hard bedding compound is good, but it also needs to be very shock resistant. The compund has to be able to stand up to the repeated pounding and shock of recoil. This is where Acra-Glas, Marine Tex and Devcon really shine. They have a certain degree of flexibility to them that makes them very tough and able to withstand the shock. This results in a long lasting bed.
The West Sytems slow cure Epoxy may work, but I will stick with the Devcon.
Bondo, Kitty Hair, standard POLYESTER resin fiberglass, JB Weld and such are very hard when set, which makes them brittle also. I have seen a rifle where Kitty Hair was used to bed the action, only to chunk out after about 50 rounds.
Not the kind of work I want my name attached to........
The slower the product cures, the stronger and tougher it will be. The cure time dictates the length of the polymer "chain". Quick setting formulae do not allow sufficient time for a long chaining to occur at a molecular level.
The longer the "chain" the tougher the end result. It also allows better "flow" time which means the compound will fill all the nooks and crannys better.
Another thing that will denote a quality bed job is the stock preperation. The stock must be properly undercut and in some instances "Anchor" holes drilled to give the bedding something to "key" into. Between the bedding and the stock you need to have a superior mechanical bond. Otherwise you will end up with a nice fitting rifle/bedding but a crappy bedding/stock relationship.
September 3, 2008, 09:07 PM
working in the marine industry for 40 plus years, worked with many epoxies. Splash Zone is one of the best. very stiff, very forgiving as to mixing ratios, machinable and xtremly tough
vBulletin® v3.8.7, Copyright ©2000-2013, vBulletin Solutions, Inc.