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Stock Care and Repair

Blo & Tung oil.

What would you say if I told you that "Boiled Linseed Oil" wasn't boiled at all? You'd say "pishaw!" I'm sure. In fact, however, Boiled Linseed Oil isn't boiled at all. Linseed Oil is squeezed from the Flax plant. BLO is simply regular Linseed Oil with metallic dryers added. These driers are what make linseed oil "cure" within a day or so. Without them, the oil would never harden. In the old days, lead was added but it was found to be unhealthy so the industry uses what are called salts of Zinc, Cobalt or Manganese. In order to help mix these driers into the oil, the raw linseed oil was heated, but never boiled. Now, let me take a second to pontificate about BLO.

Of all the oil finishes on the market, BLO is the weakest and least resistant oil finish, period. In any test, it will allow water to pass through it into the surface below quicker than any other finish out there. In fact, this is considered an asset when linseed oil was used as a base for old, enamel house paints. The linseed oil was so porous that it allowed any water to escape that accumulated below the paint surface on the clapboards or shakes of your house. This kept the paint from lifting. Why, then, did the military see fit to use it on the stocks of rifles? Well it's applied differently. It was heated (not boiled) to get it thinner, then the stocks were literally dipped into it, allowing the warmed oil to penetrate deeply into the wood. A deep penetration of any oil will help repel water and debris as opposed to just laying it on the surface with a rag. It was also extremely cheap. Later on, however, tung oil was added to the mix at the Garand factory.

Tung Oil was used for centuries but only introduced to the West about a century ago. It, as opposed to BLO, provides the best oil protective finish on the market. Like BLO, "raw" Tung Oil has driers added to it to speed the drying time. It's lighter and doesn't darken the surface as much. It builds more quickly, too, requiring fewer coats to obtain the desired finish.

So, let me be perfectly clear about why I like Tung oil over BLO. When we apply blo to a stock, we never put enough on to make any difference, really. It doesn't penetrate enough to really do the job as I've stated above. It's just too porous and in order to really "work", we'd have to leave our stocks dipped into a bath of it for quite a while to really be effective. That being said, most of us do not put our service rifles through the kind of extremes that it saw in actual combat service. We baby them, actually. BLO, then, can provide an effective cosmetic appearance but will do little to provide the tough, mechanical protection the original BLO offered. Tung oil, otoh, does provide as good a mechanical and cosmetic finish as any oil can. That's why I like to use it over BLO.

Let me also introduce you to one final type of oil, some of you may actually be familiar with. So far we've discussed raw oil and "boiled" oil (oil with driers added). The third type is called "polymerized" oil. Ever hear of "Tru-Oil"?? It's actually polymerized oil. It's oil that, with the driers, has been heated in an oxygen-free environment to a temperature of about 500 degrees F. This polymerizes the oil which makes it cure very fast, become very hard, and really resists water and moisture penetration. This type of oil is NOTwhat we'd like to see on our rifles. It's what is commonly used for commercial rifle stocks like shotguns and the like. It's hard and glossy and inappropriate for Military weapons. It's also expensive.

So, I hope this helps put more into perspective the attributes/drawbacks of oils. If I had to select one of the three I've mentioned, it would have to be the tung oil. It builds fast, is water and moisture proof, and most importantly, it's removable so that refinishing or "tuning up" of a stock is fairly straight forward by just removing the surface finish and then reapplying it.

Let me also close by saying that of all the industries, the paint industry is considered the worst when it comes to labeling contents of a can. Terms are confusing, ambiguous, inaccurate, and outright misleading. Over the recent years, the paint industry has been under fire to improve the labeling of their products but it has a very long way to go.


All About CA: Cyanoacrylate Adhesives…AKA…instant glue”

This adhesive couldn’t be more aptly named. It cures instantly, is very hard, and extremely strong… stronger than the materials that it bonds together. By far, it is one of the best adhesives to be invented in my very humble opinion. It works differently than other adhesives and cures rather than dries. The curing is effected by the adhesive absorbing moisture from the air and from the material it’s being applied to. Too much moisture is bad, however, so don’t wet your pieces. Today, CA is used widely in industry and the medical field. Yes, in some cases doctors actually glue open wounds together instead of using stitches or staples. CA also works right through oils making it a great adhesive for contaminated gun furniture.

CA comes is three viscosities or thicknesses. The best way to describe them would be water thin, syrup, molasses. The later two are usually labeled “gap filling”. The last two are the most popular with Home Center stores and is found in tiny vials, usually designed for one or two applications. This is not an efficient way to purchase CA, however. You are much better off purchasing at least the 2oz bottles which can be found at virtually any hobby store across America. There are a number of brands available but two brands you’ll see are “Hot Stuff” and “Zap A Gap”. It doesn’t make any difference which brand you use, however, as they all pretty much work identically. The larger bottles will usually also offer replacement tips so you can always have a nice, clean tip to apply the adhesive right where you need it. In addition, there are always bottles of “kicker” found with these adhesives. While the water thin material rarely need help, the thicker viscosities allow the pieces you’re gluing to be adjusted before the glue cures. Once you’re ready, you can sprits a little kicker on it and it’ll cure instantly. The kicker does not affect the material it’s being sprayed onto, by the way. Once cured, just wipe it away. Shelf life is plenty long as long as the tip is closed but moisture will cure it in the bottle within weeks if left open.

CA has two interesting attributes to be aware of. As mentioned above, it will work on oily pieces. So, if you’ve got some contamination from cosmo on that wood, just wipe away the excess but DON’T clean the piece before you glue it up. That’s because the split area usually fits perfectly together and getting cleaning materials on the two surfaces to be cleaned may affect the way they fit back together. So, do your gluing FIRST, then clean.

The second attribute it has is that sometime it “gasses off”. You’ll actually see a white vapor and maybe even hear a “hiss” as it instantly cures. Don’t breath that gas as it is pretty irritating. So little is let loose, however, that you don’t have to wear a respirator, however.

In the interest if brevity, here are the basics of when to use which viscosity of CA on your projects. We’re going to be repairing cracks in our stocks and handguards with this material. Let’s take them one at a time.

Buttstock Cracks and Splits

In the buttstocks, there are two kinds of cracks: damage splits and stress cracks. Here’s how to address them both.

Damage Splits

Damage splits are caused by dropping the rifle, or some other traumatic event. In this case, the stock literally splits along a fine line of grain. When you rejoin the two pieces, the spit line disappears and the stock looks whole again. In this case, you can use the middle viscosity of CA. Simply apply it to one of the two pieces, especially on the interior of the surface. Try to keep it away from the outer ” of the surface of the stock to prevent oozing out when you join the pieces. Immediately after you put your CA on one half, mate them immediately and hold them together with rubber bands overnight. This adhesive will cure before then but since there is little air penetration, the curing process will slow. There is no need for dowels, pins, screws, or any other type of mechanical devises. The adhesive is stronger than all of them together.

Stress Cracks

The second kind of crack is a stress crack. These are the worst as they are caused by the wood finally deciding to move away from itself. When you try to put them back together, you find that you can’t. These are usually caused by some environmental issue that’s going on within the stock. Maybe a lot of moisture got into the wood, swelling it and splitting it. Maybe too much cosmo was removed too quickly, altering the cell structure. What ever the cause, you’ll end up with a split that is noticeable, even after you glue it up.

In this case, you’ll want to build a jig that will allow you to place the buttstock into a vise or big clamp so you can help push the pieces back together without damaging the stock. Once you’ve built that jig, separate the pieces slightly, apply the medium or thick grade CA as far into the center as you can, and then immediately place the stock into the clamp or vise and close the gap as far as you dare. You will NOT be able to make it perfect. When it’s dry (overnight), you’ll have to determine what course to follow to fill the gap as best you can.

Handguard Cracks

Finally, the third fix that CA will help you with will be broken handguards. These items are usually notoriously thin in spots and will split from time to time. They can, however, usually be place together perfectly and the crack disappears. In this case, take the handguard and place it upside down on your table, and join the two pieces together tightly. The split should disappear. Here you’ll be using water-thin CA. While the pieces are joined, simply wick a stream of CA right on top of the split. You may want someone to help you hold the piece while you glue. As soon as the glue goes on, you’ll see it wick right into the extremely thin crack. To move things along, you can sprits it with the kicker and cure it instantly. Once you’ve got that initial cure, apply a second stream along the underside. Usually, this is enough to glue the pieces together and you don’t need to apply CA to the outside, thus saving you from having to refinish. Be careful, however. The water thin CA is extremely weepy and will weep everywhere. If you do get it on the outside, don’t wipe. Just let it cure and then remove it with a razor blade using it as a scraper. There is a CA remover on the market and that would work to get the stuff off the surface without sanding or scraping.

With some experience using this modern adhesive, you’ll know what, when, and where with your projects. Caution is important. This stuff will glue to you to yourself or to a buttstock or handguard instantly! This is no laughing matter as I can attest to. I’ve glued my fingers together more than a few times and it requires soaking in a solvent to get them apart without tearing your skin. The moisture in your finger tips is all that’s needed for CA to cure instantly. One final word of caution regarding this wonderful adhesive. I know of a guy who squeezed a bottle who’s tip was slightly clogged. When he squeezed, the pressure finally released the adhesive in a strong stream and right into his eye! It was painful but it is not the end of the world. Due to the amount of moisture in the eyeball, the glue basically formed a “cap” like a hard cataract. He did go to the doctor but this “cap” was easily removed but his eye was sore for a few days. Please wear safety glasses when using the thin adhesive to avoid this happening to you.

I’ll close this part of this essay by repeating the idea that experimentation and experience will go a long way in learning to use CA. Please try using this adhesive on scrap before attempting the final repair on your expensive rifle. Once you do learn to use it, however, you’ll have added an important tool in your restoration and repair arsenal.

Cosmolene Penetration

One addition to this essay was suggested by another poster. He asked that I put up these two photos sent to me by yet another poster, showing the cosmolene penetration of an old stock. I think that was a good idea so here they are. I think it's important for anyone cleaning cosmolene off an old stock to know just what they are dealing with. This is not just a matter of cleaning the surface but leaching out the cosmo from core of the wood.
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Admittedly, most of our stocks won't be this bad. However, I'd lay bets that probably 25% of them are. So, be patient with the leaching process. It took many decades of cosmo exposure to get it in. It will only take a few weeks to get it out using any of the techniques discussed at the forum. Also, know that CA will penetrate oil soaked wood and still adhere just as with dry wood. All repairs should be done before cleaning the cosmo off the stock, too. That will make is easier to clean any glue lines that might occur before reapplying a finish.


cosmo1.jpg

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