Tung Oil - How much do you actually wipe off?

[Matt Martyn]

Hi,

Just a quick question. I have been doing some experimenting with some different finishes on scrap pieces of wood, and was wondering about the tung oil. I'm playing around with some pure and polymerized pure (not the "tung" finish stuff). Now, everywhere I have read, they say to remove the excess with a clean rag, but I have never really heard, how much do you actually remove? I know its not a film building finish so you don't want to leave a nice wet coat, but on the other hand, after a few coats its not really absorbed much anymore and with a good rub you can remove all the fresh oil.

So, do you give it a quick light wipe leaving a slightly shiny film on the surface, or do you give it a good buff with a rag and take it all off?

Thanks!
Matt

[Jim Becker]

You wipe off any oil that remains on the surface of the wood after a period of time...say a half hour. This is important to maintain an even level of "sheen" as you build the finish...which with tung takes quite a while. The same holds true for BLO.

[Matt Martyn]

Hi Jim,

Thanks for the reply. So then if you wipe off any that is remaining on the surface, then I would think that you could not wipe it too much then? By rubbing and flipping the rag a few times... I dunno why I'm having trouble with this, I guess from using film finishes too much

Thanks.
Matt

[Ed Falis]

I approximate this guy's method, though not quite so intensively. http://home.insightbb.com/~jpaquay/oil_fin.txt

Currently I'm using the Lee Valley polymerized tung oil finish for a kitchen cabinet project. The only difference I notice that's relevant to the above technique is that the LV finish dries much more quickly than Watco, so you need to work in smaller batches or faster.

I wipe it all off.

- Ed

[Matt Martyn]

That link has some good info, thanks Ed!

Matt

[Steve Schoene]

With pure tung oil you want to thoroughly buff off any surface tung oil. Then you need to wait several days for it to cure, lightly sand the surface with 320 grit paper, and do it again, again leaving several days between coats. It should take 5-6 coats before you can expect the finish to be an even satin.

If you leave too much on the surface, or put on the coats too quickly, you run the risk of the tung oil developing a "frosty" look where some of the tung oil has turned white. The same thing would happen if you dried to add driers to tung oil. And, putting a varnish over less than fully cured tung oil could cause a similar white spot problems when driers in the varnish interacted with the tung oil. Also, any film left on the surface will be soft and almost gummy.

Polymerized tung oil can be left with a very, very thin film on the surface. But try to leave too much and you will get crazing down the road.

By the way there are several inaccuracies in the linked material. Raw linseed oil is a drying oil, it will dry, but it only seems like forever. Boiled linseed oil has driers incorporated, it's not just oxygenated. Partial oxygenation is what goes on to make polymerized linseed oil, though that is often not called that but called things like stand thickened linseed oil. You don't often see polymerized linseed oil, but that is what Tru Oil is.

Also, for applying Watco on open pored woods, if you don't follow the advise to flood the material on, but just give one or two very light just barely wet coatings before wiping it off thoroughly you can block the pores with less risk of bleed back.

[Ed Falis]

I'm always willing to defer to what Steve S says when it comes to finishing. Thanks for chiming in!

[Matt Martyn]

Thanks Steve! That was exactly (and more) the info I was looking for.

Matt

[Will Blick]

Steve, for what type of applications would you use Polymerized Tung Oil, such as

http://www.sutherlandwelles.com/

Do you like this finish? If so, on any particular type of woods or pieces? would it make a good finish for a work bench?

[Joe Chritz]

"Polymerization is a "cooking" process that changes the molecular structure of pure, raw Tung Oil."

Change something on the molecular level and it is something new and unique. That finish is similar to several other wiping varnishes on the market best as I can tell.

I expect it is decent finish but any film finish is probably a pour choice for a workbench. BLO/wax with a monthly wax and annual re oil is probably the best choice. Cheap and most important, easy to repair and redo.

Joe

[Steven Wilson]

some film finishes (shellac or lacquer) work well on a workbench too; very easy to repair, easy to apply, and it dries fast. Roughly once a year I just sand my bench top with 180g and wipe on a coat or two of shellac.

[Will Blick]

Steve, do you find the shellac prevents glue from sticking to the top?

Joe, any recommendations for BLO/wax. General Finishes, Minwax?

I see the two trains of thought here.... one is to saturate the wood with oil, then, continue to apply it over time.... the other is, seal the wood with a film, and let repair it over time also... both seem like sensible strategies.

I recently started using Mike Mahoneys finishes on some cutting boards, and I must say they perform very well vs. straight tung oil. The added wax seals in the oil allowing the board to go much longer between re coats. i assume the same must be true with work benches, a sealer, (such as the wax in Mahoneys formula) for the top, maybe shellac or polymerized Tung might be worthy to protect the top, and if reasonable care is taken in its use, less maint. coats? Any thoughts?