Oil for Wood

T

TheOTBalisong

Joined
Jun 28, 2012
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288
Guys and Gals,

I was wondering what is a good finish for wood. I've heard many different responses, and I was thinking Tung Oil, how good is that?

What's the process of getting a good finish on wood to protect it from moisture/sunlight/impacts.

Thanks.
 
Tung oil is great for finishing wood. However, different species of wood take oil a little differently. You have to get to know the wood you're working with. Some take Tung oil better; the denser species take "Teak oil" better. As far as "impacts", the oil won't help you much, although Tung oil will harden inside the wood and may prevent some damage from wear and tear.
As far as applying the oil, some makers flood it on for 30 mins. or so with a rag; some actually submerse the wood (in the case of knife handles) in the oil for a day or so.
 
Just remember not all tung oil was created equal. What Troop was talking about was pure tung oil and it is absolutely fantastic. I flood the wood with heavy coats until it wont absorb any more and then I buff it and finally coat with Renaissance wax to seal it. If you go to Ace or HomeDepot they sell several things called tung oil but read between the lines some of those are "tung oil finishes" that have other chems added in like polys and lacquers. Beware.

Also drying times on tung oil varies like Troop said with changes in the wood density.

Good luck!
 
It depends on the kind of wood. I would not bother with tung oil on something like lignum vitae or cocobola. These woods are impregnated with their own resins and won't really absorb the oil. You're bound to end up with a sticky mess.

On less oily woods Tung oil is very good. Use something with the words "100% pure tung oil" on the bottle. Do not use "Formby's Tung Oil Finish" as it contains no tung oil at all, it's simply thinned varnish and will dry with a hard slick film. The pure oil can be found at Woodcraft. For the first coat you want to really penetrate the wood, so thin it by half with a solvent like mineral spirits or turpentine. Just flood the wood with the thinned oil, let it sit for a minute. Depending on how "thirsty" the wood is, it may have absorbed most of the oil and the surface dried off, if so apply more oil, and repeat if necessary. Your goal is to keep the wood flooded with oil until it stops absorbing, it might take 20 or 30 minutes. At that point wipe the surface dry and let it sit for a day or two. You want to keep an eye on it for the first few hours after letting it sit, because oil will weep out of the wood pores and you don't want excess oil drying on the surface, so you have to keep wiping it down.

The next coats use full strength oil, just dap your fingers in the jar and rub it vigorously into the wood, generating heat with your fingers, then wipe off and let it set for a day. You can repeat this as many times as you like, the classic rifle stock finishes might have 30 coats applied over a the course of several months. You can build a finish with a lot of depth this way, but 2 or 3 coats is plenty for a utilitarian user finish. If you intend to apply another finish over top of the tung oil, like wax or varnish, you need to wait at least a week so the oil can fully cure. Really to completely cure it might take over a month, but in my experience a week or two works ok.

Make sure to store the oil so that it is not exposed to air, either squeeze the jar down so the air is gone before you tighten the cap, or fill the air space in the jar with something like glass marbles. Tung oil degrades fairly rapidly in the jar if it's allowed to contact air.
 
Robs92XJ said:
It depends on the kind of wood. I would not bother with tung oil on something like lignum vitae or cocobola. These woods are impregnated with their own resins and won't really absorb the oil. You're bound to end up with a sticky mess.

On less oily woods Tung oil is very good. Use something with the words "100% pure tung oil" on the bottle. Do not use "Formby's Tung Oil Finish" as it contains no tung oil at all, it's simply thinned varnish and will dry with a hard slick film. The pure oil can be found at Woodcraft. For the first coat you want to really penetrate the wood, so thin it by half with a solvent like mineral spirits or turpentine. Just flood the wood with the thinned oil, let it sit for a minute. Depending on how "thirsty" the wood is, it may have absorbed most of the oil and the surface dried off, if so apply more oil, and repeat if necessary. Your goal is to keep the wood flooded with oil until it stops absorbing, it might take 20 or 30 minutes. At that point wipe the surface dry and let it sit for a day or two. You want to keep an eye on it for the first few hours after letting it sit, because oil will weep out of the wood pores and you don't want excess oil drying on the surface, so you have to keep wiping it down.

The next coats use full strength oil, just dap your fingers in the jar and rub it vigorously into the wood, generating heat with your fingers, then wipe off and let it set for a day. You can repeat this as many times as you like, the classic rifle stock finishes might have 30 coats applied over a the course of several months. You can build a finish with a lot of depth this way, but 2 or 3 coats is plenty for a utilitarian user finish. If you intend to apply another finish over top of the tung oil, like wax or varnish, you need to wait at least a week so the oil can fully cure. Really to completely cure it might take over a month, but in my experience a week or two works ok.

Make sure to store the oil so that it is not exposed to air, either squeeze the jar down so the air is gone before you tighten the cap, or fill the air space in the jar with something like glass marbles. Tung oil degrades fairly rapidly in the jar if it's allowed to contact air.
Click to expand...

Exactly. +1 Robs92XJ

We need to collect posts like this and WIP threads into a digital book called "Bladeforums.com Guide to Knifemaking":D
 
hi,
my to sense.
any "pure" oil will seal the wood, but you will never have the hard finish you could get from varnish or shellac. i use mineral oil usp from the drugstore. it is food safe and works well on handles. soaked the handles in the oil for several days then let them dry. good protection of the wood, but they sweat oil a bit when they get hot(inside my truck on a 95 degree day).
using a finish like fornby's can give an impressive finish, but takes a minimum of 24 hours between coats and i have found it takes 5 to 6 coats at least to get a mirror kine finish. sand wood to 400 grit. clean. coat with finish. dry for 24 hours in zero dust environment. gently rub with 0000 steel wool. wipe with clean cloth. coat with finish. after about 4 or 5 coats you can see the finish come to life. plan on at least a week.
i have also been using Varathane water based poly for floors. no smell. water clean up. 90 minutes between coats. designed for floors so it holds up well.

like the idea of collecting posts like this. would give everyone a place to talk about their speciality. i am new to knife making but have been refinishing floors and furniture for over 40 years.

scott
 
Thank you so much for your insight, guys, this will help without a doubt.
But, one more question. Would Tung Oil be absorbed well by a Hawaiian Koa?
That's what I plan to make my first knife with, and when I "take the plunge" into knife making,
I want to be well prepared.
Thanks in advanced.
 
I am not too sure on the koa, never worked with it before. It's a beautiful wood, one of my guitars has it's top made of Koa. One thing I've noticed with oily woods is that if you take a rag wet with acetone or some other solvent and wipe the wood with it, the rag will turn dark. This is especially true with cocobola. So that's one way to sort of test it, the other is to just apply some oil to a peice of scrap and see if it gets absorbed. Don't wipe off the excess, just let it sit. If the wood is dry it will absorb most or all of the oil, if its an oily wood the oil will just sit on top. You can compare it to a peice of pine or oak that you know will absorb the oil.

With the oily woods I don't put any finish on them, just sand and buff and they will polish up just like they were oiled. They are usually very hard and dimensionally stable so there's no big benefit to finishes.

While I'm talking about finishes, I don't think film finishes like varnish or lacquer are good for user handles, they are slick and cause hotspots. In my opinion they should be reserved for the display case. Danish oil is an exception, since the common brands have some varnish in them, but it's such a small amount that they don't really form a noticable film.
 
I've used Danish oil on walking sticks, and it worked very well.
 
I use to use Danish Oil all the time. With good results. I quit though cause one day I was sitting there in the shop and noticed right on the can it says not for exterior use. So I switched to Tru Oil as certainly it is designed for outdoor use.
 
I've used Tru-oil with good results. I thin the first couple of coats with mineral spirits 50/50 so it penetrates better.
 
I've used Waterlox Transparent for years. It's great stuff, easy to apply,
easy to touch up when necessary, and not terribly expensive. It's also
very durable.

Bill
 
Tung Oil, Danish Oil, and Tru Oil are all pretty great. I had a nice chat with Mark at Burl Source the other day, and he's got a lot of helpful tips. If I recall correctly, he suggests sanding to 600 grit, then applying some coats of one of the above oils. I think he also mentioned using some minwax paste wax, and buffing with a t-shirt or something similar.
 
crimsonfalcon07 said:
Tung Oil, Danish Oil, and Tru Oil are all pretty great. I had a nice chat with Mark at Burl Source the other day, and he's got a lot of helpful tips. If I recall correctly, he suggests sanding to 600 grit, then applying some coats of one of the above oils. I think he also mentioned using some minwax paste wax, and buffing with a t-shirt or something similar.
Click to expand...

Speaking of burl source, I'm buying my koa from mark. :) thanks for all the help guys.
 
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