harder stock finish

[peterw]

Hi, "peterw" is my new nickname (on the old board my nick was "piteruu").
I am looking for any advice to make harder finish for the walnut stock. I tried linseed oil with dryers and oil for floor finish (based on linseed oil too). No problem with drying but surface is very soft. I can engrave it with my nail. Maybe my piece of wood (American walnut) is too soft? Is there something what makes harder surface? I didn't try tung oil and any professional oil for stock finish.

[rich pierce]

Wait a bit of things are humid.

[ehoff]

I finished my last two guns with Chambers stock finish and was very satisfied with the results. As for something to harden the wood itself there are products that claim to harden wood. Minwax and several other companies make "wood hardener" how effective they are and what effects they might have on the wood as far as color, etc. I can't say as I've never used them.

[Dphariss]

First off its wood, a material that is often very frustrating.
The problem is that as the finish gets harder it looses elasticity. When it looses elasticity it looses its ability to keep out moisture as it will tend to check or crack.
Since its already finished with oil its difficult to get it to accept more finish and this leaves a built up coating on the stock which can cause grief as well since as it wears there will be finish failures as it wears off and/or cracks or checks.
It is very difficult to significantly harden the wood and not go to a finish that is too hard.
If you try you can dent any common stock wood with a fingernail.
Now if you look and epoxy impregnated wood you will get harder wood but it weighs a ton.
The bottom line is that its a wooden gunstock and American walnut, especially western grown, can be pretty soft.

Dan

[peterw]

Minwax and several other companies make "wood hardener".

I found something like this and  I will try this.

If you try you can dent any common stock wood with a fingernail.

Yes. But I can do it really too easy. I have Investarm Great Plains rifle finished with stain and oil. It is rock hard compared to my stock.  But Investarm use European walnut (sometimes Caucasian).   

[Stophel]

Linseed oil should not be left standing on the surface of the wood.  Linseed oil will dry, but will never get "hard".  It will dry to a stiff, gummy consistency.  Linseed oil should be an "in the wood" finish, rather than an "on the wood" finish.

If you have linseed oil dried on the surface, take a piece of burlap and cut it all off.  Scrub the $#@* out of it.  Where possible, use a shoe shine motion to knock the oil off the surface.  This will leave the grain filled, but no oil on the outside, and you should then have a proper linseed oil finish.  When you hear about a "hand rubbed" oil finish, this is where all the real rubbing takes place!  It takes quite a bit of elbow grease.

For a surface finish, you need a varnish.  Resins would be boiled into the oil to make it harder and glossier.  You don't want too hard though, as it will scratch and flake off.

[Darrin McDonal]

I totally agree with Chris about the linseed oil. Frankly I wont use the modern stuff for gunstocks at all. It will disappoint you everytime because it is absolutely nothing like the 18th century version of boiled linseed oil. You can however make (a few) modern versions of the old stuff.  it does have other uses though around the shop. But to make it totally correct you would need to use lead oxide as a hardener and I dont think you should, but some may argue that there isnt enough lead in the final product to matter much. To just take bulk, raw linseed oil and carefully boil it ( outdoors away from structures) until it gets to be almost molasses thick is a better gunstock oil (by far) than modern "boiled linseed oil". Now I would use, and do prefer Jim Chambers oil stock finish to almost everything I have tried. I love the stuff. I wish it came in bulk!!!!!
Darrin

[peterw]

Chris you are right. It was too much finish on the wood surface. I sanded it and now is much better. But the wood is really soft. Thank you. It is my first build and I am learning. I will try tung oil and maybe Jim Chambers oil. 

[tg]

I like to mix Marine spar varnish with linseed oil and a bit of mineral sprits, the varnish makes for a harder finish than the plain linseed oil. Fred Miller has a write up on the use of this finish but iIcannot find the addy right now.

[Dphariss]

I like to mix Marine spar varnish with linseed oil and a bit of mineral sprits, the varnish makes for a harder finish than the plain linseed oil. Fred Miller has a write up on the use of this finish but iIcannot find the addy right now.

As I have posted before Grumbachers oil painters medium III is a varnish Damar and balsam IIRC (bottle is in the shop) that mixes well with home cooked linseed oil. At 50-50 it will make a little harder finish that is more water proof than straight oil but still soft enough to simply wear away if applied thicker.
I never use a really built up finish. I use heavy coats of thickened oil cut back when just past the sticky stage to fill walnut then top this with just enough to make a shine.
On maple linseed well rubbed off after being on the wood for  a few minutes will take on a shine without any additions if rubbed or used. But its more uniform to put on a shine coat.
Real spar varnish mixed in is a good idea as well. But most of it is plastic anymore.
Linseed got a bad name when gun stockers forgot how to make it properly and use what they made.
Dan

[Stophel]

I just finished a gun with boiled linseed oil.  By golly, I just like it.  This is stuff I boiled myself.  Started with a good quality cold pressed, purified linseed oil (got it from wood finishing enterprises).  Boiled it at a low boil for maybe an hour in my little deep fryer (it also caught fire on me, so keep the lid handy!  I let it get too hot).  Added about a teaspoon of lead carbonate, and a teaspoon of a burnt umber.  It is of very thick consistency.  Thicker than honey.  It dries like crazy.  It will skim over in the jar pretty quickly.

I put on about 4 applications and that's it.  The grain is filled.  First two coats were "cut" with just a little bit of raw pure linseed oil.  Wiped off the surface and let dry.  The next two were applied and let stand on the surface of the wood (it is so thick, that it has to be thinned some with turpentine just to get it to do anything).  Scrubbed off the surface with a coarse cloth.  That's it.  All done.  Each coat will easily dry in a day of sunlight.  I could almost do two coats a day with it.


Peter, as far as your wood,  you're just stuck with it being soft, unless you want to restock it.  Walnut can be outstanding wood, hard as sugar maple, and it can be soft as poplar, useless for gunstocks.  If the wood feels really soft, then really it is too soft to use as a gunstock, as it simply won't be terribly strong.

[Darrin McDonal]

Chris, that sounds like a good recipe you have so I have a couple of for you. Where did you find lead carbonate and how much does it take to do its magic. I know Jamestown distributers sell raw linseed oil in bulk but where are any other sources?
Darrin

[Jim Filipski]

I'm telling you lads: UGL tung oil finish
http://www.ugl.com/zarWoodFinishing/zarTungOil.php
 It's Tung oil with 10 % poly ( you will never notice the poly!) Been using it on any "hunting rifles" I built for over 20 years. & talk about "mellow look" after rubbing it down with pumice or rottenstone
Nice & flexible for wood expansion but hard to the touch! Just my 2 cents!
Jim

[peterw]

Well, now I am sure - my linseed oil finish was wrong. No problem with oil which I prepared (cold pressed, purified linseed oil, not boiled but mixed with liquid dryers and turpentine) but with my skills. It was too much oil on the surface. On the other piece of my testing wood: the same oil, 2 coats of hand rubbed finish, no oil on the surface and after 24 hours it is hard enough for me.   

[Stophel]

Darrin,

Lead carbonate is "Flake White", or "White lead".  It is the historical white paint pigment, and was used prior to titanium dioxide.  I have a huge sack of it.  Enough to poison every paint-eating baby in the state.  Got it from Kremer-Pigmente, which now, I think is handled in the US entirely by Sinopia.  Doesn't cost much...which is probably why I ended up with such a huge amount.

The boiled linseed oil I'm using now is like 2/3rds of a quart of "Varnish makers oil" from Wood Finishing Enterprises, which is a really nice quality purified cold pressed oil.  It was like $30 a gallon, I think, so it's not all that expensive.  To which, I added a teaspoon of lead carbonate and a teaspoon of a burnt umber (for the manganese content, which is reportedly a good drying agent as well).  Boiled for about an hour.  Dries like crazy.

It's too thick like this to make varnish work well for me.  I need to do some more experiments with varnish.  Too thick, and it is sticky, no matter how much I cut it with turpentine, and it gets tacky immediately upon application to the wood, and it won't level out, and I can't smooth it with my hands like I would like to.  I have some that I made that I didn't boil very long, and it stays thin and fluid, and levels BEAUTIFULLY, but takes absolutely forever to dry.  I need to find the happy medium.  Something that flows and levels, but dries in a reasonable amount of time.

I'm going to try boiling, with NO driers added and see what I come up with.

[Dphariss]

Well, now I am sure - my linseed oil finish was wrong. No problem with oil which I prepared (cold pressed, purified linseed oil, not boiled but mixed with liquid dryers and turpentine) but with my skills. It was too much oil on the surface. On the other piece of my testing wood: the same oil, 2 coats of hand rubbed finish, no oil on the surface and after 24 hours it is hard enough for me.   

If you do not heat the oil and kill the acids in the oil they will retard the dryng and require much more Japan Drier or what ever you might be using. This is why limestome of some other source of calcium carbonate is used. As the oil is heated the limestone will start to bubble long before the oil is really hot.
The "boiling" also darkens and thickens the oil both are desirable when used as a stock finish. I boil about 1/2 the oil 2-3 times the further thicken it. Clear stock finishes are a modern invention and they do not enhance the wood as well as dark oils do.
If you have a lot of driers in the oil it may kick over too fast if you boil it now. With hardware store boiled oil (which has drier added already), I only add about a tablespoon or less of Japan drier to a gallon. There are other things that can be put into the oil to speed drying.

To fill walnut for example I use heavy coats of thick oil, really gooped on then rub it off when dry enough that it no longer gums up the 0000 steel wool (burlap works too).
On maple I just rub it on then wipe off the excess in a few minutes. In 3-4 coats a pretty good finish can be done on maple.

Dan

[Dphariss]

Darrin,

Lead carbonate is "Flake White", or "White lead".  It is the historical white paint pigment, and was used prior to titanium dioxide.  I have a huge sack of it.  Enough to poison every paint-eating baby in the state.  Got it from Kremer-Pigmente, which now, I think is handled in the US entirely by Sinopia.  Doesn't cost much...which is probably why I ended up with such a huge amount.

The boiled linseed oil I'm using now is like 2/3rds of a quart of "Varnish makers oil" from Wood Finishing Enterprises, which is a really nice quality purified cold pressed oil.  It was like $30 a gallon, I think, so it's not all that expensive.  To which, I added a teaspoon of lead carbonate and a teaspoon of a burnt umber (for the manganese content, which is reportedly a good drying agent as well).  Boiled for about an hour.  Dries like crazy.

It's too thick like this to make varnish work well for me.  I need to do some more experiments with varnish.  Too thick, and it is sticky, no matter how much I cut it with turpentine, and it gets tacky immediately upon application to the wood, and it won't level out, and I can't smooth it with my hands like I would like to.  I have some that I made that I didn't boil very long, and it stays thin and fluid, and levels BEAUTIFULLY, but takes absolutely forever to dry.  I need to find the happy medium.  Something that flows and levels, but dries in a reasonable amount of time.

I'm going to try boiling, with NO driers added and see what I come up with.

Linseed oil without dryers added, store bought "raw" oil, heated will thicken and darken I suspect but without some driers its not going the make a good stock finish.

Dan

[peterw]

I have to break two barriers: language and chemistry, so please forgive me my translation if you can't understand.
There is inscription on the my dryer's ("driers"?? - what is proper?) bottle :
"manganese salt and calcium salt of caprylic acid +cobalt"
I mixed it 50/50 with linseed oil.

[WadePatton]

well?  the conversation stopped mid-sentence.

If i boil my raw oil too long, can i not thin it back down with less-boiled oil.  I do know better than to use raw--but have a gallon from years ago when i was trying o follow some Clyde Baker recipe.  I'll boil it all, but maybe to different levels.  

But then i didn't and still don't understand "driers" like the above poster asked about.  I really don't understand about oils and poly's and "plastic" the related chemicalese.  I suppose i don't have to understand so long as my stain/seal/topcoat all work out.

If my test wood colors nicely with AF then, i'll stain with it.  if not, i'll copy Keith Lisle's technique.  As this is a first time and pretty wood, I'm planning to do a lot of test work on the scraps coming from this blank.

i find no finishing only fitment/fab stuff in the tutorial section.  i've been searching (via remote engine of course) and reading here for 3 hours.  this was the most appropriate thread to re-open.

cheers, tia

[Curt Larsen]

Like an earlier reply, I use marine spar varnish, linseed oil, and turpentine in equal parts.  I use hardware store linseed oil with this mix and have on all of the furniture that I build too.  With my stocks, I generally use 3 and more coats of this stuff until I'm happy with it.  It dries pretty fast in the sun (when there is some).  I then rub it down with 000 and 0000 steel wool between coats.  The marine spar varnish has UV protection in it.  I use Epifanes spar varnish on my boat and like it.  It comes in gloss and rubbed effecct versions.  It is pricey at the boat supply stores or on line.  Other of my boating friends think there is no problem with hardware store versions.

Curt L

[WadePatton]

Thanks Curt,

Is that the standard chemically "boiled" LO?  I have both types.  LO is the preferred anti-seize/thread locker for custom bicycle wheel spoke nipples. 

[Dphariss]

Raw linseed oil will not "set" so I would not mix it with stock finish.
As I pointed out in another thread I have a 60+ year old military rifle finished with raw linseed that still has liquid oil in the stock.
For initial sealing thinning thick boiled oil is best done with real turpentine but it must not be overly thinned or it can reduce oil penetration into the stock.

If used as a varnish, IE as a significant coating ON the surface linseed needs to be in the form of a VARNISH with some resins in it. This would then be similar to the old varnishes used on firearms.
This is what many original rifles were finished with. From what I have read Rosin was a common resin.
The Marlin Ballards, for example, were finished with an oil varnish. Even 100 years after application this varnish is still elastic and the film will not break in minor dents in the stock.
The Bridger Hawken has a dark reddish brown varnish that has survived  where its not worn off and still has not flaked or cracked as modern hard varnishes typically do.
Modern poly varnishes are very wear resistant but they also look like plastic finishes. Being old enough to remember the early "impervious" plastics of the late 20th century I avoid them. Having had a friend who used Varathane on some REALLY high end breechloaders this does not appeal either since by comparison its ugly.
If finishing a walnut stock with linseed oil its necessary to properly prepare the surface if a shiny finish is desired. A poorly sanded stock is not going to work very well. Seal with a slightly bodied real boiled oil cut with turpentine that has be allowed to set in a shallow dish for 2-3 days.  The stock is then filled with fairly thick coats of a heavy bodied BOILED linseed oil, usually 3-4 coats for American Walnut. The fill coats removed from the surface with 0000 steel wool or even burlap as soon as its slightly set but not really gummy. In direct sun this will occur in 2-3 hours. Attempting to remove it when its too wet will result in steel wool or burlap fibers adhering to the stock. When its dry enough this will not occur to any extent and any such fibers will wipe off easily.
Once filled the stock can be polished with oil and rottenstone. Put on a thin coat of light weight boiled oil and let it set in the sun or overnight. Rub this back with a cotton pad wet with oil and then sprinkled with rottenstone. Work until the coating is completely removed. Wipe dry and either wait over night to examine again for remains of the top coat or apply a microscopic layer of the lighter weight oil and let it set. This should produce a very shiny finish and while the top layer will wear it will really be near impossible to tell since the wood is highly polished and is "filled"with dried oil.
For a hunting gun where a duller finish might be wanted skip the rottenstone.
If the final coats are comprised of a soft varnish it will not water spot as linseed will do. Linseed even if water spotted it will release the moisture back the air. Any damage to this finish can be instantly repaired with a very light wipe of the damaged area with the original top coat.

For those of you who have no desire to make a finish a good store bought alternative is Tru-Oil cut 50-50 with store bought boiled oil. Tru-oil is a hard, very fast drying oil varnish. Or a phenolic oil varnish. Its cheaply made stuff but with additions of more   oil its useable.
Chambers oil finish should also be good but for a sealer I would cut it with real turp. Turpentine, the real stuff, is resinous it you let it set in an open container like a shallow dish it will turn to a gummy pine sap like substance.
The idea of varnish, back in the day anything that dried to a shine was called either varnish or a spirit varnish like shellac, is to increase water RESISTANCE (not "proof") and increase wear resistance. Since varnish is a surface coating in typical use wear resistance is important. But this has to be balanced with elasticity since if the finish is too hard it tends to fail in exterior applications it will also fail if even slightly dented something that softer varnishes will not do unless the object striking the stock is pretty sharp or its heavily struck. This is from examination of original gunstocks and comparing them with the results of wear and exposure on guns finished in the 20th century with modern hard varnishes that are often petroleum solvent based or more recently petroleum with synthetic resin. Going to any gun show and looking at rifles with a lot of use will be illuminating. The modern (from maybe 1900 on)   varnishes tend to chip/check/peal. They break when dented. Then they will leak liquid water even if it does not flake off.


Dan

[Dphariss]

Like an earlier reply, I use marine spar varnish, linseed oil, and turpentine in equal parts.  I use hardware store linseed oil with this mix and have on all of the furniture that I build too.  With my stocks, I generally use 3 and more coats of this stuff until I'm happy with it.  It dries pretty fast in the sun (when there is some).  I then rub it down with 000 and 0000 steel wool between coats.  The marine spar varnish has UV protection in it.  I use Epifanes spar varnish on my boat and like it.  It comes in gloss and rubbed effecct versions.  It is pricey at the boat supply stores or on line.  Other of my boating friends think there is no problem with hardware store versions.

Curt L

A good spar varnish used as you have been is technically sound.
But as with many things Spar Varnishes are not all created equal.

Dan

[WadePatton]

Thanks Dan,

Aged turp--got it.  

As to rottenstone--that's another mail-order item for me.  Is there a reasonable facsimile or home-made version?  But then I am not going for glossy.

Point of learning:  how does overthinning reduce penetration?  Seems counter-intuitive, but i'm here to learn.

thinned to seal, thick to fill, not-so-thick to finish.  

hey, where's the Grumbachers?  Can i get a reasonable hunting finish without it?

oh, wait--i'm chasing my tail here.  saw other reply-nebbermind me.

[Dphariss]

Thanks Dan,

Aged turp--got it.  

As to rottenstone--that's another mail-order item for me.  Is there a reasonable facsimile or home-made version?  But then I am not going for glossy.

Point of learning:  how does overthinning reduce penetration?  Seems counter-intuitive, but i'm here to learn.

thinned to seal, thick to fill, not-so-thick to finish.  

hey, where's the Grumbachers?  Can i get a reasonable hunting finish without it?

oh, wait--i'm chasing my tail here.  saw other reply-nebbermind me.

I am told that too much turp will result in the turp soaking in and the oil not so much. This from a guy who has forgotten more than I know, though it do not seem he forgets a lot when I think of it.
Places that sell artists supplies will have grumbacher products.
"Michael's" is a place to start I think they are a national chain.
As I posted elsewhere there is a great deal of info on boiling oil and its usage in the archives.
I would also point out that some acid reducer must be used in cooking the oil. I use crushed limestone. Failure to reduce the organic acid level will slow drying of the finished oil.
Dan