Linseed Oil & Turpentine finish for wood

Quest

Active Member
http://www.audiokarma.org/forums/showthread.php?t=120044

I read the question of using tung oil on wood and it reminded me that some people do not know about using natural oils to protect wood. An oil finish that have the advantage of easier applications and much less of a chance to screw up and, if necessary, it can be brought back to life quickly with another application of oil. Using linseed oil and gum of turpentine, here is a way to use natural finish on wood. I’ve used it many times and never messed it up.



Someone threw out these faded Minimus-7W (Walnut) speakers because the veneer finish was faded. Look at them now.





If you’ve got wood equipment and it just needs a refinishing then let me recommend using an oil finish. It makes a beautiful satin sheen, is easy to apply, protects the wood and can be rejuvenated easily.

The first oil finish happened by accident, back in the days of early English Feudal castles and in the baronial halls. In these grand establishments, the first oak interior trim was left unfinished. As time passed, however, the wood began to take on a rich color from the gases and greases emanating from the cooking pots hung over the open fires, and eventually, a beautiful and colorful finished resulted.

From this beginning, the process of producing a rich oil finish developed and became more refined. Now it is done with applications of hot linseed oil with each application rubbed into the wood and allowed to dry. An oil finish is strictly for the ambitious. It takes time, patience, and endless rubbing, but in the end, it’s well worth it, because you can’t find a more functional finish then this ancient one. The difference between an oil finish and other finishes is that the oil finish is IN the wood and not ON it. In addition to imparting a rich color to the wood, it also makes it impervious to the ravages of heat, water, stains and ordinary wear. It also adds the advantage that it strengthens the wood by locking strong resins in the wood fibers.





It can take many months to complete an oil finish, but during the process, the furniture being finished can be used as usual. The simplest procedure is to brush on a hot 50-50 mixture of boiled linseed oil and turpentine, allow it to dry for about an hour, and then wipe off the excess. Repeat the process every day or two until four or more coats of oil have been applied. This will give you a good finish that needs no waxing and can be washed as frequently as needed to maintain cleanliness. The oiling process can be repeated to renew and preserve the finish from time to time, over a period of months, and even years.

Before the oil finish can be applied, however, the old finish must be removed from the wood and sanded to a glassy smoothness with 5/0 garnet finishing paper. Next, wipe it clean with a damp cloth and dry the dampened surface quickly by directing heat on it. An electric heater or an infra-red heat lamp is ideal for this. I’ve even used sunlight to help it dry. When dry, use sandpaper or 00 grade steel wool to remove any whisker that may have been raised by the moisture.

There are several different methods of applying the oil. You can apply undiluted boiled linseed oil to the surface and rub it into the wood with the heel of your hand. Keep rubbing until the oil has been completely absorbed into the wood, and then add more oil and rub further. Repeat this until you feel that the wood can absorb no more oil. It is a good idea to rub oil into the undersurfaces as well in order to keep the wood from warping. Keep rubbing until there is no oil film left on the surface.

If the application of oil raises the grain, you can sand the surface with 8/0 garnet paper or rub with 00 or 000 steel wool as often as necessary during the process. With some open-grained woods, it is advisable to use paste wood filler in order to get a perfectly smooth surface. Filler, if applied to the bare wood before the oiling process, will cut down the wood’s absorption qualities and cause the oil applications to build up faster with less work. It will also result in a lighter-colored finish. If you want the finish to be darker, the filler can be added after an application of oil has been rubbed into the surface.

The applications of oil should be repeated every day for the first week, then once a month for a year, and once a year thereafter.

If you want to add a tone to brown woods such as mahogany and walnut, you can add a little dark red oil stain to the oil before applying it.

Another method of achieving an oil finish is to mix boiled linseed oil with pure turpentine in the proportions of 2 parts oil to one part turpentine. This mixture can be applied hot or cold. The hot mixture will set faster and result in a darker color. To heat it, use a double broiler. This mixture should be applied generously with a rag to a small area at a time and rubbed vigorously with a hard polishing cloth for 10 to 20 minutes. The rubbing friction will generate heat to bring out the luster. Wipe off any excess oil, especially from molding and crevices, before it has a chance to get sticky and hard.

Two applications of oil should be rubbed into the surface the first day, and the process repeated at least two days later with another coat. Subsequent applications can be spaced from a week to a month apart, making sure that each coat is thoroughly dry before applying the next. From 5 to 20 applications of oil in all will produce a fine, mellow finish which can be freshened up with additional applications as years go by.

For a higher sheen, after the final oiling has had time to dry for three or four days, the surface can be rubbed down with pumice and rubbing oil, and if a still higher polish is desired, follow up in a few days with rottenstone-and-oil rub.

I hope to see many oil finishes in the future! Have fun refinishing and showing off your equipment.
 
There was an old Gunsmith saying on oil finishing a stock, that went something like this.

Once a day for a week, once a week for a month, once a month for a year and once a year for the rest of your life.

…John
 
Great job on the Minimus and very nice write up.

I would've never thought to use linseed oil and turpentine on wood. I use them all the time in oil painting. But not on wood. Linseed oil just by itself kinda dries musty smelling. So I'd prefer the citrus oils. Especially on big speakers.

Whatever oil you use it does wonders and brings out the natural beauty of wood.

Cheers
 
It might be a great idea to try the citrus oils. The gum smell is very strong. I use the mixture outside but it doesn’t matter; once I start using the gum I swear the smell ends up in the house and the garage.

I should add the warning about leaving folded rags with the linseed oil/gum. As it evaporates, it could generate enough heat to catch fire. There is a chance of a spontaneous combustion at least that is what I’ve been told. I’d play it safe. It is summertime and we don’t need any fires.

Trying an oil finish with other oils could be interesting.
 
The reasoning behind tung and linseed oils are that they are of the curing veriety. There are many curing and semi-curing oils out there. Just be sure the one you use falls under this veriety.
 
Excellent write up on using oil Finishes. I wish I would have had this information about 4 weeks ago when I refinished my KLH-17's I tried Lindseed Oil the first few days, but didn't like the results as it was a bit dull, then turned sticky. All this was my fault for not knowing how to apply it. I finally removed the excess Linseed Oil from the finish and applied Tung Oil, and got the results I was looking for. I really do like the results from oil finishes. Thanks for the excellent info - Mike

http://www.audiokarma.org/forums/showthread.php?t=111535&page=2
 
I tried Lindseed Oil the first few days, but didn't like the results as it was a bit dull, then turned sticky.
http://www.audiokarma.org/forums/showthread.php?t=111535&page=2

One of the "tricks" with linseed oil is wiping it off thoroughly. This stuff will cure but it's very slow which is why there's the old mantra of once a day for a week, once a week for a month, once a month for a year....for applying a finish. Usually, I leave the oil on the surface for about 15 minutes (varies with the weather) and then wipe it off really well. I've also found that after a few coats, one has to wait more than a day in between coats for it to completely dry...so I never quite got to once a day for a week....

I now tend to prefer a 50/50 mix of BLO and tung oil. It dries a little quicker than just BLO and still gives that oil sheen that I love.
 
I find that the first application works best with Linseed oil on Walnut veneer. Don't apply too much, just enought to saturate the wood. Rub off excess. Linseed oil and gum of turpentine after. That give that deep oiled look.

Ron
 
Boiled linseed oil cures faster -- regular linseed oil may take days.

I blend curing oils with varnish and have been pleased with the results. It gives the best of both worlds.

dew.
 
Folks...I have played around with several of the curing oils, and one that frequently gets missed is walnut oil itself. It is close to tung in curing, but is significantly slower to do so. I just can't tolerate the smell of many of the finishing oils out there, which just seems to last forever. There is a fairly expensive walnut oil out there that is roasted, so it has a kind of smoky aroma that is quite appealing. This is the finish I prefer, and it does make for a nice, deep grain pop, without the need for stain.

Enjoy,
Rich P
 
I agree about using oils on veneer. I like both teak oil and boiled linseed oil and I use a lot of both when refurbishing speakers.
I'd like to add a caveat to the otherwise excellent description of how to use oils. The writer mentions steel wool. This should be avoided unless stringent measures are taken to protect the drivers, inside of the cabinet and all environmental surfaces from the shed particles. Little bits of metal are death to voice coils, and they'll all make their way in there sooner or later. There are alternative abrasives based on nylon pads that do a similar job and bear no risk of ruining a driver. I'd hate to see a neophyte follow those directions without due care for the drivers and wipe out something that can't be replaced.
 
I am on the last 2 coats of tung oil on a pair of KLH 32's and have been very pleased with the look of the finish. My neighbor is an old-school cabinetmaker(50+ yrs exp) and when I was discussing finishes with him, he highly recommended lemon oil as an alternative to tung oil in the way of a more natural oil. I have a 2nd pair of 32's I am going to do with lemon oil once the weather here becomes better for outdoor work. I do all sanding outdoors.:smoke::smoke::smoke:
 
I find steel wool + very open pore wood (oak) = bad

It would gather up steel "lint" in the pores that was impossible to get out. Was I doing something wrong?
 
Back
Top Bottom