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Bedding thoughts ...

4K views 57 replies 21 participants last post by  Oldblades 
#1 ·
... like many of you I have used JB-Weld for many years as a bedding medium. It is inexpensive ... and readily available at Wally World, Lowes, Home Depot and most hardware stores. If one is careful it does an excellent job.

However, it does have one major drawback ... it has a fairly low viscosity in the mixed state .... darn it ... let's be honest ... it runs everywhere. This makes it difficult to use in tight, nadgery spots in the stock ... it won't stay put until you get the action snugged in place ... and not even then !

Was thinking the other evening ... normal practice while sitting in front of the idiot box ... ! Remembered that somewhere in my junk boxes there used to be a small tub of micro-balloons - left over from kayak/canoe mould patching chores. Yep ... there was ... so finshed up by mixing a few small batches of JB with pinches of micro-balloons added to the resin before stirring in the hardener.

It worked ... the resultant uncured mix DOES NOT RUN ... stays where you put it ! One unexpected result though ... the cured JB is not dead hard and brittle like a regular mix ... it has a slight flexibility, yet resists "sharp-edged" compression.

I found that as little as 15-20%, by volume, of micro-balloons to just the resin was sufficient.

Hmmm ! Could this make it more efficient as a bedding agent ? Remember the use of elastomeric materials I proposed years ago as a dampener/tuning medium ... later adopted for the US Olympic Air Rifle team rifles.

Mick - The Fuzzy Limey
 
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#3 ·
I've used the JB Weld method another poster mentioned to stop the running. I use the 24hr style JB and let it sit for 30-45 minutes before spreading it inside the stock for bedding. the 24 hr stuff has a long working time. after about a half an hour i start testing it with a spreader stick until it is about the thickness of warm peanut butter and then start to bed. JB is cheap enough that you can mix up a test batch to play with until you get the feel of how long to wait.
 
#4 ·
Good to see a post from you Fuzzy!
Got a question, what are the micro ballons made of? I'm trying to figure why the JB wouldn't get all crumbly ?
Wonder if the ballons would make Marine Tex a better bedding compound? (stuff I used would be glass hard but brittle)
Take care friend,
warren
 
#17 ·
Hi Warren ... long time no see/hear ! I'd figured that after Sandy last year, the OBX were so far offshore that you'd been annexed and converted to a Limey by now - lol !

The beads I have are finer than the bset flour and are of a phenolic resin. All the sample mixes I did are still very hard yet flexible after a couple of days curing. I re-bedded the barrel section of a 455 "Fuzzolution" stock this morning with some of the mixture - (24 hour JB) - turned out excellent. This was a stock that had previously had a heavy Varmint barrel installed and now fitted with an American.

Mick - The Fuzzy Limey
 
#6 ·
Hmmmmmm.....I have some of that microballon stuff that I use on wood turnings when I need to fill voids, etc. with epoxy.

I have about settled on Devcon as my favorite bedding compound, as it has all the qualities I like...plenty of working time and stays in place.
 
#8 ·
I stumbled on to something regarding JB Welds viscosity last winter. I keep it in the shop which maintains temp at about 40 degrees when I'm not in there.
I had to warm the JB to the point where I could even get it out of the tube.
At about 50-55 degrees was a nice temp to mix and get some 'staying power'.
So I thought that I would try sticking it in the fridge first on my next project.
 
#9 ·
Fuzzy,

You might stop by a hardware store and pick up some graphite dust near the locks and keys. It makes good thickener that sets hard and makes the JB nice and dark black.

Keep it away from any air movement, even breathing near it can make a real mess.

Oldblades, be careful with low temp settings on epoxies, you can get away with some range adjustments to make it thicker or thinner, but you can also wind up with a sticky mess that never hardens. But, if you get some that doesn't quite set hard, like Fuzzys micro balloons, you might try a heat soak to finish. I use an old electric/oil radiator, but you can set an oven to 170 F, then turn it off except for the light and put the parts in for an hour or two. Be sure your SO is away for the day.

Bob
 
#11 ·
Mick if you have ever seen the bedding kits from Midway called "Miles Gilbert" they COME with microballoons! I have bedded about 6 rifles with the kit and the microballoons in the kit work great.

In my AcraGlas days of the 70's and 80's I used "kitty fir" or chopped fiberglass for the same purposes:

1. Does not fun as much or at all depending on mix.
2. It almost eliminates the shrinkage straight epoxy has./
3. Greatly strengthens the bedding.

Recently I was reminded why we called it "glass bedding" for so long. I have a Rem Mod 700 .243 I bedded in one of the very first fiberglass stocks sold by Brown Precision in the late 1970s. These were REAL fiberglass hand laid up in molds and filled with foam almost like a surf board. For the first time in 30 years or so I took the barreled action out of the stock. Bedded with AcraGlas and chopped fiberglass the bedding was clear as glass and almost as hard. I was amazed at how good my second bedding project looked all these years later.

As for the microballoons in the 6 stocks I have done so far the stuff seems to hold up pretty well.

Many people forget that JB Weld all ready has one filler and that is powdered steel.

I recently got some AgraGel. I was surprised Brownells does not recommend glass in Acragel and so I bought a tub of their Powdered Aluminum. The also have Powdered Steel and Powdered Stainless Steel. You have to watch the powdered steel because it can rust right in the bedding if exposed to weather.

Getting back to your point thje microballoons do work quite well to stiffen up the epoxy and keep it from running.
 
#13 ·
I have a Rem Mod 700 .243 I bedded in one of the very first fiberglass stocks sold by Brown Precision in the late 1970s. These were REAL fiberglass hand laid up in molds and filled with foam almost like a surf board. For the first time in 30 years or so I took the barreled action out of the stock. Bedded with AcraGlas and chopped fiberglass the bedding was clear as glass and almost as hard.
Vincent, you're telling your age now. :D

Your comments bring back a lot of memories. I too purchased one of those Brown Precision stocks for a Rem 700 short action. I also did my bedding back then with the Acraglas, but don't recall if I used anything to stiffen it with or not. My buddy did have a lathe, and we turned pillars out of aluminum rods. I just recently sold that stock - still had the papers that came with it - to that same buddy.
 
#12 ·
Vincent you just gave me the idea to give chopped carbon fiber strands a try.

Sometimes a weave gets loose and some fibers fray out while I'm cutting the fabric and then when saturated in epoxy, the frayed fibers seem to almost gel up with the epoxy. I call it "carbon snot" because that's pretty much what it becomes. If "kitty fur" works, maybe carbon fibers will too!
 
#14 · (Edited)
#19 ·
Then that would be Devcon 10110.

For the life of me i cannot see why anyone would mess with JBWeld or anything similar when Devcon is there for less $$, and FAR superior in strength & cured hardness, which is the key thing in a bedding compound.

I got my last 1Lb tub of Devcon for $34 shipped.
That equals ALOT of tubes of JBWeld...
 
#22 ·
Try PC-7 epoxy available at ACE and a number of hardware stores its in between a glue and a putty has about an hour working period and is setup in 24 hours. Comes in what looks like two Kodak 35mm film cans stuck end to end. Its a 50/40 mix so that parts pretty easy. DOES NOT RUN yet squishes out very well. Has excellent adhesion properties and Neutral Kiwi Shoe Polish works great as a release agent. After about 7-8 hours you can pop the barreled action use an Xacto Knife to trim up the bedding and put the barreled action back in to finish setting up.

I have now done three rifles with it and have two more planned.
 
#27 ·
The Truth

Want to really know what works?

What epoxy?

What method?

The truth is there are many, many ways to bed a rifle and a number of compounds that work just fine. It is down right silly to say Compound X works better than all the rest.

Really? I personally have used 4 or 5 and for the life of me I can not tell you X is better than Y and neither can any one else. I have done shrinkage testing and that matters in how you apply it. If one shrinks more than another only matters if you are dead set on not doing a "skin coat" after the first.

These little 22s do not stress a bedding compound like a .375 H&H.

Devcon, AcraGlas, AcraGel, Miles Gilbert, Slow set JB Weld are all going to work just fine and if the person doing the job knows what they doing you will NEVER know the difference unless you take it apart and looks and then all you will learn is MAYBE which one it is.

THAT is the truth.
 
#28 ·
Want to really know what works?

What epoxy?

What method?

The truth is there are many, many ways to bed a rifle and a number of compounds that work just fine. It is down right silly to say Compound X works better than all the rest.

Really? I personally have used 4 or 5 and for the life of me I can not tell you X is better than Y and neither can any one else. I have done shrinkage testing and that matters in how you apply it. If one shrinks more than another only matters if you are dead set on not doing a "skin coat" after the first.

These little 22s do not stress a bedding compound like a .375 H&H.

Devcon, AcraGlas, AcraGel, Miles Gilbert, Slow set JB Weld are all going to work just fine and if the person doing the job knows what they doing you will NEVER know the difference unless you take it apart and looks and then all you will learn is MAYBE which one it is.

THAT is the truth.
Or as the old saying goes...."there is more than one way to skin a cat."

Though for the life of me, I never was clear on why anyone would want to skin a cat. :rolleyes:
 
#35 · (Edited)
Good for you, you'll never go back.
Now, be careful to get the setup JUST the way you want it BEFORE applying the Devcon. If it turns out "less than stellar", it will take a solid carbide diegrinder bit to get it out ! Devcon sets far harder than JBW or any fiberglas bedding. "Granite" is what comes to mind when i have to trim the stuff !'

A tip on mixing - Devcon wants 9:1 ratio of putty to hardener. People complain about how impossible that is, but it's easy, assuming you have a little digital scale ($15 at harbor freight).
Use some sort of disposable plastic tray to mix in- (the top from a clear cookie package, or similar) . Measure the length and width of the stock area to be bedded. Spoon a strip putty, that same size, onto the tray. The thickness of the strip will be the thickness of the bedding you are planning to have ( the depth to which you relieved wood under the action) . I usually go for 3/16 to 1/4 thickness for max rigidity.
Now that you have the amount of putty that you'll need, place the tray on the scale. Divide the weight measured by 9. Hit the TARE button. add hardener to the tray til it reads that 1/9th weight you calculated.
Mix well til even gray color with no steaks of hardener visible. Apply.

I like that method because it gets me just the amount i need for the job, without alot of waste left over
 
#39 · (Edited)
*I drill a grid pattern of holes on all bedding surfaces, switching to a dremel with a small bur and inserting into 25% of the holes, and swivel the dremel in a small circle to auger out a cone shaped recess. I blow all dust out with compressed air. Then I mix a batch of Devcon, and fill a large syringe with it and attach a large hypo
needle. The syringe that I use to apply the mud has the nipple where the needle attaches removed for better flow. I fill all of the holes from the bottom up, injecting as I go. Then I apply a layer of mud to the whole intended bedding area and a layer on the action. I lay the action in the stock with the front of the stock tilted up and let gravity slowly work, which pushes air out as it goes. I then bolt or strap it together, and the wait begins.
The process of creating conical recesses, then filling with a syringe works great and produces a good mechanical lock with NO air bubbles, guaranteed. The work comes
out smooth as glass. Makes bedding jobs easier, neater and cuts down on waste!!!

Anyone reading this who has done a number of bedding jobs can appreciate how its not easy to get the compound where you want it, and how nice it would be to have a syringe and needle big enough to apply the compound with precision and intent.
I'm currently working on a way to put the bedding syringe into a caulk gun to make it even more user friendly.

Here are some pics of a few of my recent Devcon bedding jobs using this method:











DrGunner
 
#40 ·
Nice info and pics DrGunner! OldBlades you will love it.

Here's another bedding job with Devcon, just after I popped the barreled action out. Release agent was Kiwi neutral wax.



It starts out sloppy but finishes up really nicely!

 
#43 ·
Thanks for the suggestion!

Don't you have trouble with the black Kiwi sticking to the bedding???

I have read that you can mix by weight, but since I have access to LOTS of free medical supplies, I went that route. One of the things I get for free is large syringes. They are included in almost all surgical packs, and go unused and discarded at an alarming rate. The nurses know to save them for me. Once I figured out how to use them to mix Devcon, I never looked back- because the measuring system also doubles as an airtight storage container.

I tried Kiwi black once when I ran out of neutral.
I don't like it, mainly because for me, it stuck pretty hard to the Devcon, which makes it hard to discern later whether there is shoe polish or some schmutz on the bedding that could interfere with installing the action.
Looked like this :



I managed to scrub most of it off of this one:



DrG
 
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