Tung oil

[Robby]

I picked up a quart of, "Belen 100% pure Tung oil" at a  flea market, cheap. It appears to be unused. What would I have to do to make this into a usable stock finish? I have done a little experimenting, and it doesn't seem to dry on its own,at least after four days, I can drag my finger across it, and pick up a trace. I don't know that much about tung oil, but I'm sure I read somewhere that it will produce a nice hand rubbed finish and would be very water resistant.
Robby

[Daryl]

Don' t know about pure Tung oil - but suspect the tung oil finishes have drying agents in them.  I've use Tung oil as a stock finish & prefer True Oil.

[smart dog]

Hi Robby,
I have used tung oil as a stock finish for over 20 years.  For the first coats to seal the gunstock, I mix the tung oil with polyurethane varnish - 25% tung, 25% urethane and 50% turps.  That mix will soak in deeply and give the wood a nice warm glow.  It also is a very water resistant finish.  I paint that finish on until it is obvious that the grain is starting to fill then I switch to tung oil with a tiny bit of Japan drier added.  You need to experiment with how much drier to add because humidity and temperature in your area will make a difference.  In addition, I like to vigorously hand rub in that finish so I don't want it drying too fast.  I put about 1-2 ml of drier per cup of oil (I make small quantities so that I use it all up on a project).  That corresponds to a few drops in the oil.  The alternative, which I mostly use, is to buy polymerized tung oil such as Sunderland Wells that does not need drier added.  The tung oil finish is one of the best around whether you want to hand rub it to a low gloss or build it up and rub it back with rottenstone for a higher gloss.

dave

[T*O*F]

I picked up a quart of, "Belen 100% pure Tung oil" at a  flea market, cheap. It appears to be unused. What would I have to do to make this into a usable stock finish?

 
I use this same product once in a while.  I use it "as is."  First coat....slather on heavily with a lintless cloth.  Let it penetrate for a few minutes, then buff it off with a t_shirt.  Hang in sun to dry for 24 hours.  Further coats are done with your fingers, rubbing in only a drop at a time.

I have done a little experimenting, and it doesn't seem to dry on its own,at least after four days,

Being a flea market find, you have no idea how old it is or how it was stored.  It could have been stored several winters in an unheated garage with temps below freezing.

[Robby]

Thanks Dave. Seems like a simple, straight forward process. I tried Woodcraft and Woodworkers supply and both said they don't carry "Japan Dryers". Where do you get it?
TOF, I will be experimenting with this before using it for real. Thanks for the reminder.
Robby

[MKemper]

Robby,  you will find Japan Drier at your local Home Depot.  I was told to go there by the folks at Woodcraft Supply.  Best not to ask the person in the paint dept. where the Japan Drier is as they probably have never heard of it...but its there with the thinners, etc.

[Dphariss]

It my not have enough driers to be of use ifs its pure tung oil.
??
Try it on a wood scrap. If it will not dry in 2-4 hours in the hot sun its probably not suitable.
Properly formulated its a good top coat over straight linseed oil.
Did you know the Chinese used it to to seal runways they built for the US Army Air Corps in WW-II?

Dan

[Randy Hedden]

Japan Dryer can be found almost anywhere they sell oil paints in a tube.  The japan dryer is mixed with the oil, olive oil or linseed oil, that oil paints are made from.  A small bottle of it doesn't cost much and it doesn't take much as an additive to oil finishes to make them dry faster.

Randy Hedden

[Ken G]

I've bought Japan drier at Ace Hardware.  It's with the paint thinners and strippers.
Ken

[Simon]

Artist turpentine, which is pure,filtered,etc. mixed with Japan drier, in equal parts will dry oil faster than Japan drier by its-self.  Do not use "TURPINTANE" Which is fake and sold in paint stores.  I don't know anything about the Japan drier sold in paint stores.  I buy mine in artist supply stores or hobby lobby.Artist turpentine is marked on the label as " artist turpentine" and costs quite a bit more than what you buy in paint stores.

Mel

[Dphariss]

Artist turpentine, which is pure,filtered,etc. mixed with Japan drier, in equal parts will dry oil faster than Japan drier by its-self.  Do not use "TURPINTANE" Which is fake and sold in paint stores.  I don't know anything about the Japan drier sold in paint stores.  I buy mine in artist supply stores or hobby lobby.Artist turpentine is marked on the label as " artist turpentine" and costs quite a bit more than what you buy in paint stores.

Mel

For best results turp should be "aged" in a shallow dish for 2-3 days so it can take on more oxygen.
Then mixed in small batches.
Japan drier will work  but I would heat the oil after adding it if it linseed. Don't know about tung oil.

Dan

[SR James]

Dan, how much heat?  Warm, hot, simmer, boil?  I'm asking because I sometimes use boiled linseed oil and Japan Drier as a finish
but I've never thought about heating it after mixing.

[T*O*F]

If it will not dry in 2-4 hours in the hot sun its probably not suitable.

Drying is a process of solvent evaporation.  Tung, linseed, and other natural oils do not dry, they cure forming polymer chains in the process, and it takes more than 2 hours to do that.  That period of time only allows any solvents added (turpentine, etc) to evaporate out.  These solvents only make it thinner for easier application, and it follows that a thinner film will dry faster than a thick one.  However, just because the solvents have evaporated does not mean that the base is cured.  Repeated applications without adequate curing time only lead to thicker films which never harden.  This is why so many complain about soft or sticky oil finishes.  Each coat needs the required time to cure before adding the next, however long that may be.  Many old references speak of the long times required for a good oil finish.

If you are in a hurry (and it seems like everyone is today) use something else that dries quickly.

[Simon]

I have used artist oil paints on carved birds and the oils in the paints is very slow to  dry.   I am not sure what type of oil is used to mix with the pigment, but I believe it is linseed,as I have used linseed to thin dry paint.  Anyway the artist oils takes about a year to dry to the point that they can be sealed with varnish.

On the few guns that I have built, I put on 3 or 4 coats of linseed in  about a week, with each coat well rubbed in, then a very light coat after each use.  I don,t use wax on top of the oil.   Paste wax such as Johnsons is a patrolium product abd will soften the oil over time.  IMHO if you use wax it should be carnuba was which is plant based.