Does Tung oil raise the grain?

[pencheff]

After reading many posts about the wondrous virtues of true Tung Oil I finally bought some 100% pure T.O. from Woodcraft to give it a shot. So far I've tried it on three bowls of cherry, walnut and maple.

I used two or three applications of the T.O. on all these pieces. I did all these more than a month ago and I can still smell the Tung oil on all of them. Is that normal?

I finish sand all my stuff through 400 grit then apply the finish off the lathe. The walnut bowl is still as smooth as it was before I applied the T.O. The cherry and maple bowls however are now rough to the touch as if the T.O. raised the grain. Again, is that normal?

I like the appearance of the T.O., but it doesn't look that much different than a Danish Oil or Mahoney walnut oil or, for that matter, boiled linseed oil.

After all I'd read about how marvelous this stuff is I'm a bit disappointed, but maybe I'm missing something.

Please share your pro & con experiences with Tung Oil.

 

[Barry Elder]

Tung Oil

If you are using 100% tung oil, from what I have read it makes months to cure, depending on the weather. If you are using 100% tung oil finish, it has been diluted with something that will speed the curing. Again, the length of time depends on the depth of the snow, etc. Relative to some of the other finishes that are not tung oil based, it does not darken the wood much at all. It is my finish of choice. And as far as I know it does not raise the grain. Water raises the grain, not oil. Check Russ Fairfield's site. He has a great site with tons of info on finishing.

 

[MichaelMouse]

I don't like the stink of tung oil either. Persists for as long as it takes to fully cure. Cures a bit satin in look, to my eye, versus linseed's transparancy.

Since oil isn't polar, it doesn't bind to the cellulose, bulking it out. Instead it fills air spaces. I'm sure you've noticed that water left on oiled or waxed surfaces will raise the grain. They're two different items.

Which is why I think you may have trapped a bunch of moisture under a drier surface. When it got to the surface, it couldn't leave fast enough, so it raised the grain. I've seen it happen on works of haste, might be the culprit here. Might be a bit of perception as well, since walnut is open grain and the others not.

 

[waltben]

Unless Woodcraft's changed the label, I believe they recommend cutting it with mineral spirits or some such, not using it straight out of the bottle. I had a bottle several years back that I used with good success when I wanted a waterproof finish. It cured in a day and left no odor every time. I used about 3/4 of the bottle until the remainder got too dark and thick from air and age. I've tried Waterlox, also a tung oil finish, but diluted with other things, but it's also quite expensive and difficult to keep from darkening/thickening quickly. Since I'm only interested in waterproofing utility pieces, I've been using Formby's tung oil since (a lot cheaper, considering how quickly the stuff ages once opened). None of these have taken more than a day to cure or left an unpleasing odor.

Another thought - did you wipe off the excess after applying a coat? If you built up too thick a covering, that may be why it won't cure. I apply a coat (first one quite liberally), wait about five or ten minutes, then wipe off the excess. If I wait too long, it hardens enough that it's very difficult to remove. I let the piece sit overnight to harden, buff lightly with a Scotch-brite pad and apply again. I put two or three coats on a pepper grinder or salad bowl like this and haven't ever had a problem. For decor items, I prefer a quality either Danish or antique oil to get a wax-like sheen, rather than the more glossy tung oil look.

 

[jdsilwones]

Hi Greg. I’ve been using TO for many years and for many reasons. Some points to keep in mind.
When I say TO I mean pure 100% tung oil. The light nutty oder smells good. You know what I’m talking about.
TO will not cure overnight.
TO will not raise the grain on wood. When it cures it will haze on the surface of your work, too much and it feels rough to the touch.
TO doesn’t look much different then other oil finishes.
When fully cured you will not smell the finish.
Test your finishes before you use them. Take a clean empty pop can and put it upside down where you place your work to dry/cure. Put a few drops of finish on the bottom and spread it around with your finger. Don’t mess with it after that. The curved smooth surface shows you many things about how the finish flows, adheres, and dries.
I’ll PM you the way I use TO if you like.

 

[Bill Boehme]

Just remember that it is an oil and not a finish so you don't want to leave a film on the surface. I use pure tung oil and it is one of my favorites, but it is also very expensive. After liberally coating the bowl and letting it sit for around 15 minutes, I wipe it as dry as possible and then a couple hours later wipe it again because it will bleed a bit. I don't recall using more than one application as additional oiling isn't going to make a great deal of difference -- remember that is not meant to have a surface film. If it is a very soft wood, a second application might be useful, but I would make certain to not let it sit too long and to wipe off all of the surface oil. If there is a smell, then it is either the wood or you have let it accumulate a gooey mess on the surface which will never have a satisfactory look.