Home Forums Hunting & Shooting General Big Game Finishing Walnut stocks

Sitka Deer,<BR>I have never heard of an oil finish actually increasing the woods ability to absorb moisture. I am not disputing you, only asking how you came to such a conclusion. Oil finishes have been a standard finish on gun stocks for quite a few years before there was such a thing as plastic stocks. Many knowledgeable people still use it. I do not live in the Alaskan rain forest but I do hunt my rifles in every kind of weather. I bed the action, float the barrel, and seal all the wood inside and out and have not had a problem to date with shifting impacts. <BR>The Chinese used Tung oil to waterproof their ships (maybe it was to sink them).<BR>However I am always willing to learn something new. I am just baffled. [img]images/icons/crazy.gif" border="0[/img]

Thunderstick, this is a guess as to why oiled wood may absorb water.<BR>Wood is made up of cells called lignen these cells are what wood fiber is composed of. As wood dries the lignen cells shrink in diameter but very little in length. Replacing the water in the cells with an oil will cause the cells to swell back up, but not to their original size. The oil on a stock is only a few molecules deep into the wood. Lignen fibers being roundish have interstictual space between each cell voids. These voids provide a conduit for water molecules to travel to the dry lignen cells benigth the oiled cells thus causing the wood to absorb and retain moisture. In order to stop this you must make a barrier on the surface of the wood that is water proof IE: plastic etc. <BR>Wood is natural in design to absorb water molecules. In order to seal water out you use a molecule that is larger than water molecule to plug up the lignen cells and the interstitual spaces between cells. To penetrate you use a smaller molecule. <P>Science 101<P>Bullwnkl.

I guess people used oil finishes on gunstocks in order to attract rather than repel moisture. <BR> [img]images/icons/crazy.gif" border="0[/img] <BR>I still find it difficult to believe that an unfinished gunstock is more impervious to the weather than an oil finish.<BR>Are these observations relative to all oil finishes or applicable only to some?

Well, I don't want to dispute anyone here who has given suggestions. Most of the suggestions have been excellent and just show the many different methods employed to finish a stock. Obviously, some work better than others- for instance, I tried the spray on Birchwood Casey Polyurethane a couple of times and gave it up as a waste of time. The coats were just so thin as to be practically nonexistent, and the cans didn't hold enough to finish a stock completely. In fact, I went through 2 cans on one stock and I still think I didn't put enough finish on the stock, after sanding between coats, to make a satisfactory finish. Your milage may vary.<P>As to the issue of moisture, I guess you have to look at moisture and finishes from two different perspectives. <BR>While I agree the plastic finishes will seal out the ambient moistures, they also seal IN the existing moisture in the stock which can be anywhere from 7%-12%. As long as this stays stable, you probably will have a stable piece of wood as long as you own it, but in severe conditions, this moisture in the wood can affect the outer finish. Excess heat or cold will cause this moisture to want to migrate out of the stock, with nowhere to go. What happens next can take many forms, blisters under the finish, bubbles in a finish that is not quite completely cured, or just warpage at a point of concentration such as figure in the wood. Or, what is more likely is this scenario. Most stock finishers who use the plastic finishes, don't use them on the interior places, action area, butt stock, etc.. This area is usually done in oil of some sort because you don't require a nice looking finish in these areas. Now, what do you suppose happens when you have a piece of wood with different finish porosity on different sides? The moisture will leave (or collect) faster from the oiled side than the plasticized side, leaving one side of the stock drier (or wetter)than another area. Warpage or wood movement is the inevitable result. <P>Other finishers prefer to use oil finishes of many different types, Linseed oil, varnishes, Tung oil, combinations of all of these, etc... The reasons they have worked for so long is because of the fact that they breathe and the wood has a chance to acclimate slowly to ambient temperatures without sudden changes. Yes, the wood may take on moisture and also bleed off moisture when ambient moisture levels and temperatures dictate it, but the amount is small and usually doesn't affect the stability of the stock because the transfer is gradual and over the entire stock. <P>Obviously, some stock woods, especially highly figured woods, will warp and move more than others. This has little to do with the moisture, as temperatures and other factors can also cause this. A good stockmaker will see this fault in most stock blanks and discard them when they are discovered. Also, consider this- the most highly figured stocks are also the most prized for high-end rifles. These rifles almost always get some type of oil finish and a hand rubbed texture is desired at the end. Keep in mind that the varnishes most used by stockmakers that seem to be more waterproof than the other finishes mentioned, Tru-oil, linseed oil, tung oil, are also oil based. <P>I am definitely no expert on this subject, but I have learned a bunch from this thread and many others like it on this and other boards. Many have contributed and I appreciate all the different opinions on this subject, especially Ray Atkinson who is always generous with his many years of experience. I won't say I disagree directly with any one on this thread, but I will have to give some thought to some of the suggestions. If nothing else, to see if it fits my methods and needs at the moment. Take care- Sheister

Thanks a lot Shiester,<BR>Your post makes a lot of sense to me.

I've been out killing fish and have not stopped in for a couple days and am heading out again real soon, but have a few things to add here. Hope I have not stepped on any toes too hard.<P>Oil, even cured completely has an affinity to water vapor, actually frank water as well; therefore the admonition not to put wet cups on the oil finished side table at Grandma's house. It will only absorb a given amount, and then no more, if it is used as a ship finish. Some will migrate through the finish and be absorbed by the wood, but if the wood is always wet it simply reaches an equilibrium point and stays there.<P>Now when the same piece of oil finished wood is out in the air and subjected to constantly changed relative humidity it takes up and gives off water all the time. And because the relative humidity never stablizes, it is always moving.<P>On the linseed oil thread under gunsmithing I think I remember going into more detail about it.<P>I hope is was understood I was not suggesting a piece of unfinished wood would soak up less frank water than a piece of oiled wood, because that is clearly not the case.<P>Sheister made some excellent points about highly-figured woods moving around more than straight grained woods, but one very nice exception is tight fiddle-back figure which actually is quite a bit more stable than straight figure. Fiber lengths are longer, the wood is harder and stronger, in curly, than the same species when it is straight.<P>The logic of finishing different areas of a stock differently escapes me, also.<P>Another concept which helps understanding wood and water is the difference between bound and free water. Green wood is full of water, sometimes as much as 200% (water content is usually measured as a per centage of the oven-dry weight of the piece of wood. Hence a 1# oven-dry piece which weighed 2# when wet had a moisture content of 100%)<P>When the wood is dried, free water leaves first. It is what is inside the cells, vessels and interstices. This water removal does not affect the size of the wood, therefore there is no warpage as the free water leaves. At about 25-35% the bound water starts to leave. It was electro-chemically attached to molecules of lignin in the cell walls, or solvent for various extractives in the wood, mostly in the vessels.<P>The removal of bound water is where the going gets tough in wood drying as this is where rot and stain often occur and where drying defects start. If the wood dries too fast the surface gets dry enough to take a set and when the inside dries it shrinks and causes stresses, up to and commonly including honey-combing inside the wood.<P>Different woods dry differently for a million different reasons. The biggest reason for the differences is the pore size of the wood; gums, resins and other extractives present in those pores; figure, grain run-out and knots; thickness of the blank and many, many more. <P>The one thing Sheister said which I hope is a misunderstanding is the moisture content of his blanks. A piece of wood reaches atmospheric moisture content outdoors of about 12-15% (vs. oven-dry) but then needs to be dried to 6% and then if kept there for quite some time, years help, the wood will stablize at the lower moisture content and become much more stable, even with bigger swings in moisture content. <P>Each time a piece of wood cycles, even over a range of a per cent or two of water content, it reduces its tendency to move. That is why old stock blanks are prefered over more recently cut ones.<P>Sheister is absolutely correct about an oil finish being the right finish for the custom guns and the nearly uniform use of them by the high-end gun makers. Two points here though; my finish looks just like them, because it is an oil finish; these are the same guys who often call glass-bedding heresy.<P>This has rambled and gotten much too long, thanks for bearing with me. No offense intended or taken.<BR>art

Art, <P> I hope we can respectfully agree to disagree on this topic.<P> I was at my stock duplicator's place when he measured the moisture content of my blank and several of his best blanks- some worth several thousand dollars- and the moisture content of mine was about 13%, his were anywhere from 8% to 12%. All these blanks, including mine had been stored inside for many years. Mine had actually been in a heated shop for at least 5 years. The stocks in the stockmaker's shop were dry and anywhere from 5 to 30 years old. I have found that most furniture makers like their wood to be around 6%-8% moisture content or maybe a bit above. The reason being that most homes change temperature/moisture levels often and lower than this will cause moisture migration into the woods which will in turn cause the wood to move and warp. Wood floor installers also insist on these moisture levels and will leave the wood in the home to be installed sometimes for several weeks until the moisture level stabilizes at ambient levels, as I do with furniture wood in my workshop. Usually, this is about the best guarantee of avoiding problems later on. <BR> The electronic moisture meter he uses reads at least 1" into the blank, so surface moisture is not the only measurement and he wouldn't trust it anyway. <BR> Moisture changes are constant in an oil finished stock, that is a given. Also, the oil used on your grandmother's furniture is definitely not the same oil as that used on fine stocks. Interior grade finishes don't have the same solvents, plasticizers, or waterproof fillers included in exterior grade finishes. <BR> I have and do use the plastic finishes on stocks, in fact my stocks are about 50/50 oil finishes and polyurethane/varnish finishes. I find the "plastic" finishes to be slightly harder to work with, but beyond that, I enjoy rubbing in the oil finishes by hand and watching the wood transform a small step at a time.<BR> Art, I seem to be reading in your post that moisture just pours through an oil finish, as long as the wood will absorb it. Actually, it has been my experience that even in damp weather (not monsoon weather we experience here at times) the wood will absorb very little moisture- certainly not enough to cause major problems, but possibly enough to cause the barrel channel to move enough to contact the barrel.<BR> Another thing I have heard from many sources- once the wood is dry, very little moisture will be absorbed through the sides of the lignen fibers, most of the moisture absorbed by wood is through the end grain,since the fibers are like long straws and hollow. So sealing the end grain is mandatory when sealing a stock properly.<BR> I submit that whatever stock finish you use will work perfectly if applied properly, taken care of properly, and maintained. If you are in a location where severe weather is commonplace and your rifles are subjected to it, you should definitely consider one of the Poly or Epoxy finishes for your stock- or buy a plastic stock and stop worrying about it! Heck, my elk rifle wears a plastic stock and it doesn't hurt my feelings one bit! LOL- [img]images/icons/smile.gif" border="0[/img]- Sheister

Thank you for all the information. My question would be this: how will all of these small differences, in moisture content affect the performance of my rifles, with walnut stocks? How can one mount the action, into the stock, to minimize the changes in the wood? Art, the two boys next door are just hammering the silvers, at Ship Creek. Every day they come by with a limit and very nice sized fish, for inlet silvers.pak

Pak, <BR> In your area, I would probably go with the Poly finishes due to the amount of moisture you will inevitably encounter.<BR> The most important thing to avoid problems, no matter which finish you use, is to be absolutely sure that all the surfaces of the wood are completely sealed with the same finish you are using on the outside of the stock. That includes under the butt pad, the barrel, action, trigger area, the bolt slot and recesses for the bolt stops, and the action screw holes. Even a small slip up in this area will cause more wood movement and problems than you want to deal with.- Sheister

Sheister<BR>No hard feelings, anyone may believe what they wish. My background in wood technology is in the drying end of it as much as anywhere, and even patented a process used extensively in your area to dry difficult species.<P>If you have seen kiln-dried tanoak or madrone lumber on the market, it went through my process. Lots of other species get it as well.<P>I personally shudder to think about a stock built at 13% moisture content. Frankly, I question the accuracy of the meter used. HoW is it that lumber stored at my house, and houses and shops all over, produce wood which equalizes at 6-8%, yet the duplicator's doesn't? I would test the meter with a piece of similar wood (and do so on a regular basis) and see what is up. Simply test a small piece, weigh it, oven-dry it and reweigh it.<P>Realize too that a meter is measuring electrical resistance in a piece of wood, simply because the resistance is the same does not mean the wood is the same moisture content, it only gets you close.<P>You make a good point about the perception I'm making it sound like there is an open flood gate. Obviously the absorption and release of water is fairly slow, through the finish. But it is faster than when the wood is bare, when compared to an oil-finished stock. It is enough to cause plenty of problems in a fore-end prone to moving.<P>The concept of wood absorbing water vapor through the end grain only is entirely false, and actually weighted to the side grain when the extra surface area of the end grain is taken into account. Wood absorbs and releases water in all directions, but moves differentially in each direction, with changes in moisture.<P>As far as the finish you choose, realize that I am talking about the oil component of the finish. Most finishes have lots of plastic in them, but that does not have much effect on how the oil reacts in the finish.<P>Got guests at the door, will add more later.<P>Hope I am not annoying you Sheister, wish you could have made it up for that fishing trip, then you could have seen what I am talking about with my epoxy finish.<BR>art

Art, this is getting interesting but I think we are "bending" the thread a little. Maybe I can make it next year and we can discuss it over a beer or something.<P> Suffice it to say that the blank was 13% when turned, I would think that the several weeks since being turned, setting in my dry, heated shop would have brought it down a notch or two. About 8-9% seems to be the ambient working moisture levels around here, I guess that's what we get for living in a rainforest most of the year. Once I move to Central Oregon next year, I'm sure I'll be seeing drier conditions and then I can test your theories a little better. I'm always open to learning something new. Take care- Sheister

Pak: It depends on how much work you really want to go through. There are gun makers specializing in basically hollowing out a fancy grained walnut stock and filling it with inert plastics and steel to basicaly give the feel and look of wood and the rigidity and strength of synthetics.......<P>Time and money are your hurdles......<P>Tex

Art, I have a quick question for you since you seem to have a world of experience in this subject.<P> Most of the gunsmiths I know prefer to work with air dried wood instead of kiln dried. I've heard many different reasons for this, usually boiling down to the fact that kiln drying deforms the cell walls of the wood, which can weaken it and make it more prone to breakage and warpage. I've always wondered-is this an old wives' tale passed down through generations of stockmakers or is there some basis of fact in this belief? What is your take on this subject?- Sheister

PAK<BR>Only have a minute here, but apologize for not answering your posts more directly. A finished stock is a tough thing to do very much to, other than glass bedding and free-floating. If you care to give a call or stop by I would be happy to show you what I know, and it would be lots easier than trying to type it all out. I'm in the book and live real close to Hoppy's old place.<P>Sheiester<BR>Kiln drying is a method for moving wood through a process as cost-effectively as possible, with only as much degrade as the end users will tolerate. The process of speeding the drying does not do anything for the wood. It is absolutely an inferior product, under all circumstances, when compared to PROPERLY air-dried wood.<P>The problem is simply that stresses are created in the wood by rapid drying, over time, these stresses cause change in the wood which translates to warpage or checking, or both.<P>The damage is caused by the wood reaching about 6% moisture content and taking a set. This set can occur at any level within the wood, even in a layer within the wood. The relaxing stages in the usual kiln schedule are designed to reduce these, but are used just enough to reduce damage to a tolerable level. <P>Wood which has never reached 6% is still moving quite a bit. There have been some classic wood movement studies done which graphed the movement. They are amazing and telling.<P>The wood is such a minor part of the whole cost of the new stock, when compared to the time devoted, that I would not use kiln-dried, except under very unusual circumstances, which I could not even imagine at this point in time. I try never to say never, but using kiln-dried comes real close to being a never situation, to me.<BR>art

I am a complete novice when it comes to wood, heck, we don't even have trees on the prairies.That said I got the bug to restock a few rifles and bought some walnut. All three rifles were single shots, 2 H&R and a Browning B 78. After sanding and steel wool I loooked for some oil and wanting to avoid the hassle of preparing linseed oil I grabbed a can of Watco Danish Oil finish. It says it is for interior use only but even though my rifles are used in rain etc. they are not stored outside. I found the finish to be very durable and pleasing to the eye. This finish is said to polymerize with the wood and does repel moisture to a satisfactory degree in my climate. The material goes on easy and I wiped any excess off 20 minutes or so after applying. There are several tints available and I choose "fruitwood" as the "walnut" stain is far to dark. Fruitwood gave a slight highlite to the grain and avoided the "muddy" look of darker stains.I gave the stocks up to 15 coats rubbing each down with a coarse wool sock in between. Not a custom finish but superior to factory finishes.

JJ;<BR> This is a long thread and I've skimmed over parts of it, so if this has been mentioned, I didn't see it. If you use an oil finish like True Oil be sure and let the first coat dry thouroughly. No matter how heavy or light you apply that first coat, set the gun aside in a dry warm place for at least a couple days before you add a second coat. If the first coat is not completely dry when you add the second the finish will gum up and you will never get the finish to harden properly.<P>Dan Johnson

Sitka Deer,<P>If you don't mind,I have a question for you.<P>I need to finish the stock on an M1 Garand. The rifle is already glass bedded, so I'm reluctant to use oil as the finishing agent. How suitable would your epoxy finishes be in this application ? I'm also looking for a matte to semi-glossy finish. There are too many brilliantly shiny competition rifles out there for my taste.<P>Regards,<BR>Scott

JJ--Back to my original answer to your question. I have never had a problem with steel wool leaving pieces of metal in the stock but I use the steel wool for whiskering and then had used a tack cloth to remove all the standing dust so perhaps the tack cloth removed some small steel splinters. I have only done about 6 stocks but I still stand by the Flecto Verathane as a finish. If you followed some of the advice given previously, you can see how applying 20 coats of tru oil and then waiting a day or two for things to dry, you could wait a month of two before the thing was completely dry and finished. The Verathane dries quickly and can be applied easily without fear of drips etc. You must let it dry however, in a place with no dust as dust will adhere to any finish while it is still wet. The comment about using 400-600 grit paper is also right on. The very fine paper cuts so little wood that it really only takes just a few minutes to use the 400-600 paper and it will impove your finish. Look at it like this--each finer paper should remove all the traces of scratches or imperfections left by the prior sand paper. Try the Flecto, you'll like it.

Scott<BR>There are no compatability problems with epoxy and oil. The answer will vary with the finish on the stock, if there is one. The linseed oil thread under gunsmithing should answer most of your questions, but feel free to ask here, or email me for more specific answers.<P>Virtually any finish can be turned into an eggshell luster job with the application of rotten stone in mineral oil, on a soft cloth.<P>Murf<BR>Watco water-spots readily, and does not compare favorably with other finishes in terms of durability, toughness, or hardness.<P>Polymerization is the process that oil finishes cure through. Hydrocarbon chains link and cross link through several different chemical means, but they do not link with the wood, beyond the mechanical grip applied to the wood.<P>Steel wool is a very bad idea on stocks, except possibly the first step in the final buff-out. Any bits not removed have the potential to create a very ugly mark, at any time.<P>Rolly<BR>When Tru-oil is applied in the very thin coats it should be applied in, it cures extremely rapidly, allowing 3-4 coats a day. Once you have 20 or so coats applied, I like to let it cure thoroughly before buffing-out, but that still can be done in a few weeks, or less.<P>The varathane is a reasonable finish, though it builds too much for my taste and makes sharp corners hard to maintain.<BR>art

Sitka, Shiester,<BR>On a scale of 1-10, each assuming that their favorite finish is a 10; in comparison how would you rate a factory finished Remington, so that I can get an order of magnitude on what we are talking about? My question only relates to weather protection and durability and excludes aesthetics.<BR>How would you rate a straight tung oil finish on the stock both inside and out?<BR>How about a boiled linseed oil finish? <BR>Thanks