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View Full Version : Tung Oil: When do I stop?



Nine Thumbs
04-09-2007, 04:42 PM
I'm finishing a project using Pure Tung Oil (not tung finish). Since I don't have any mineral spirits, or anything to mix it in and I'm too lazy to get any, I'm using it straight. I rub it in with a clean cloth, wait 15 minutes and then wipe it off. I then repeat 24 hours later. I know I'm supposed to wait at least 7 days before rubbing out the finish, but how many coats am I supposed to put on? It doesn't look any different than it did after the first coat, so how do I know when I'm done?

RionM
04-09-2007, 07:14 PM
The first time I used Pure Tung Oil (actually the only time I have used it), I put on 9 coats. It was several coats too many and probably should have stopped at 4 or 5 coats.

It was put on walnut and I didn't buff it out until the fifth coat (using #0000 steel wool). It took a lot of elbow grease to get the sheen I wanted. If I had buffed it out after the second coat, I probably could have stopped much sooner. No problems as it turned out but just a lot of extra work.

I would use Tung Oil again.

Jeffk
04-09-2007, 07:40 PM
Tung oil tends is a "drying oil" and catalyzes when exposed to oxygen. After the first 2 coats it's tough to get any kind of penetration. After 2 or 3 coats let it see up a couple of days and rub out an inconspicuous area to see if the finish suits you. Keep in mind that you want enough oil to provide the finish that you are after but too thick of a coat will be tough to rub out. Finish with a coat of paste wax after rubbing out and you should be fine. HTH

DougB
04-10-2007, 12:19 AM
It may depend on what type of wood you are using, and what you are making.

For a Walnut bar top I made, I put on 10 coats of Pure Tung Oil (first few thinned with Mineral Spirits, the rest hand rubbed on).

For several "turned" projects on the lathe, I have put on 2 coats (not thinned at all). It is kind of fun putting the finish on with the lathe spinning.

If you have not tried hand rubbing in Pure Tung Oil, you really should.

Whatever method you use, if you don't put a film finish over the PTO, you should plan on re-applying the PTO every so often. I have had to apply additional coats to the bar top twice since last Christmas.

mtaviator
04-10-2007, 12:32 PM
I have finished a few gun stocks with tung oil and had great results. I wanted a smooth satin finish and had good luck with rubbing the tung oil in with fine sandpaper which made kind of a slurry that would fill any voids. Can't remember how many coats I did but it was a lot. The finish still looks perfect after about 5 years or so.

Nine Thumbs
04-10-2007, 12:36 PM
I've tried wiping it on, I'm not really sure what you mean by hand rubbing it in. I'm also assuming that rubbing out means buffing either with a cloth or #0000 steel wool. I have one project that got some white residue showing up after about a week, which I got rid of with a cloth, then rubbed with the steel wool until I couldn't get a white mark by running my fingernail over it.

Sonny Edmonds
04-10-2007, 09:15 PM
It didn't take me long to stop at all.
It tastes terrible! Why would you want to put oil on your tongue? Mine works fine without any oil, frankly.... ;) I still have most of the can of it.
I think it actually tasted worse than Limey's single malt Scotch. But I didn't try putting the oil over ice.
Maybe you should try that... put it on the rocks. :7

:D

[link:home.att.net/~paul.edmonds/|Sonny Edmonds ]
Saugus, CA
"Precision Firewood Specialist"
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DougB
04-10-2007, 10:11 PM
>I've tried wiping it on, I'm not really sure what you mean
>by hand rubbing it in.

Just pour some Pure Tung Oil directly on the wood, then use your hands to rub that oil into the wood. Rub hard and quickly and you will soon feel a bit of heat as the friction warms the oil...that is hand rubbed and there is nothing I can compare that to. Very nice feeling indeed.

>I'm also assuming that rubbing out
>means buffing either with a cloth or #0000 steel wool.

I buffed my project with an electric buffer that I got from Harbor Freight - very easy to do and really brings out the shine in the finish.

>I have one project that got some white residue showing up
>after about a week, which I got rid of with a cloth, then
>rubbed with the steel wool until I couldn't get a white mark
>by running my fingernail over it.

I have not experienced that with what I have used Pure Tung Oil on. No white residue at all. More likely for me, the oil seeps back up out of the wood and needs to be "rubbed out" or at least wiped off. And the grain gets raised and needs to be sanded out with another coat of PTO and 600 grit wet/dry sandpaper. That has worked well for me.

Please, let us know how the PTO treatment works out for you. I am really interested in this since I have limited experience with PTO but I really like what I have experienced with it so far.

Thanks,

DougB
04-10-2007, 10:13 PM
Dang that is funny Sonny. Too funny. :7

Nine Thumbs
04-11-2007, 07:53 PM
>Just pour some Pure Tung Oil directly on the wood, then use
>your hands to rub that oil into the wood. Rub hard and
>quickly and you will soon feel a bit of heat as the friction
>warms the oil...that is hand rubbed and there is nothing I
>can compare that to. Very nice feeling indeed.
>

I was under the impression that you shouldn't get Tung Oil on your skin. The can I have has a "in case of contact, wash skin immediatly with soap and water" warning. I've been wearing vinyl gloves.

I do think I'm going to get a buffer. HD sells some cheap Ryobi ones for about $30.

DougB
04-11-2007, 10:31 PM
>
>I was under the impression that you shouldn't get Tung Oil
>on your skin. The can I have has a "in case of contact,
>wash skin immediatly with soap and water" warning. I've
>been wearing vinyl gloves.
>

Probably just a CYA on their part. What brand did you get? I got Behlen's and the MSDS is here:
http://woodworker.com/cgi-bin/FULLPRES.exe?PARTNUM=849-209
<edit: replaced link did not work without a sign on - you have to click on the MSDS Sheet on the page above>

The important info in that MSDS to me would be the following:

III. HAZARDS IDENTIFICATION
Routes of Entry: None Known.
Medical Conditions Aggravated: No medical conditions affected by exposure.
Immediate (Acute) Health Effects
Inhalation: No hazard in normal industrial use. No hazard in normal industrial use.
Skin Contact: Substance may cause slight skin irritation.
Eye Contact: No hazard in normal industrial use. No hazard in normal industrial use.
Skin Absorption: A single exposure is not likely to result in the product being absorbed through the
skin in harmful amounts.
Ingestion: May cause vomiting. Mildly irritating to mouth, throat, and stomach. Can cause
abdominal discomfort.

I do not feel any reluctance to rubbing un-thinned PTO in by hand...in fact I really like it. :)

I did NOT hand apply the first few coats, which I thinned with Mineral Spirits, because I AM reluctant to have extended skin exposure to Mineral Spirits.

Nine Thumbs
04-11-2007, 10:53 PM
I have Behlen's as well. It says I can put it on with the palm of my hand, but also has the warnings about exposure. It also says "avoid contact with eyes", which is a pretty good idea for pretty much everything except normal saline.

I tried rubbing it in with 600 sandpaper on a cherry box I though was done, but the grain came up a bit. I really liked how it looks for now, but I'll have to see what happens when it dries. I may try that with some of the other things I'm testing it on.

DougB
04-11-2007, 11:29 PM
When the grain raised on some Walnut that I had used PTO on, I used 600 grit wet/dry sandpaper with PTO to knock the grain back down. That seemed to work well on the Walnut - I have not tried it on Cherry yet.

wayne86
04-12-2007, 10:07 AM
For me the more coats i put on, it took forever to dry. In fact weeks. I would not use it again