Replies

1. 
   Norse | Dec 08, 2003 09:11pm | #1

   I often use poly over tung oil but you have to wait until the tung oil is completely dry, can be weeks or months. If you can smell it, its not dry. Thinner applications dry faster.

2. 
   hepaticus | Dec 08, 2003 10:45pm | #2

   Yes, you can put poly over tongue oil or boiled linseed oil. It works fine. I usually wait a week or so, but the oil will take months to fully dry (and stop stinking) under the poly.

   Also, consider the finish described by Garret Hack. A  mixture of boiled linseed oil, turpentine and polyurethane. This is the easiest finish I have applied, and it builds up a fairly nice protective finish after several coats. I usually put on three coats of this, and a coat or two of straight gloss poly on the most exposed surface (table top etc.). I then buff off the gloss to a matte finish and wax the surface.

   MRY

1. 
   Bonka | Dec 09, 2003 01:36am | #3

   How will lacquer work over tung oil?  Could one add Japan drier to the oil?

3. 
   Paul_Snyder | Dec 09, 2003 04:55am | #4

   If the table is in a warm, well lit space, the oil should be cured enough in a week so you can apply a more durable finish over it.

   If you're willing, next time try Waterlox (.com) original varnish. It's made with a blend of tung oil and phenolic resins that not only make it a very durable finish, but it will give you the look of an oil/poly finish wihout the added product and curing time. An alternative is Behlen "RockHard Tabletop" varnish; it's made with the same ingredients, though it's a short oil varnish and cures a LOT harder (brittle) which makes it a good candidate for rubbing out if you wanted to.

   The oil/varnish/thinner recipe is the list of ingredients for danish oil. There are a few variations; but they all have very similar characteristics. Not as durable as a straight varnish/poly.

   Paul

1. 
   SDBaker | Dec 09, 2003 05:26pm | #5

   Thanks for the help.  I thought it would work fine since oil and poly are mixed together in some commercially available products.  Once I have finished applying the oil, I will move the table inside the house where it is warmer, and give it time to cure before applying the poly.  I will post a picture when done.

1. 
   Paul_Snyder | Dec 10, 2003 01:50am | #9

   I look forward to seeing the finished product!

   Add the General Finishes Arm-R-Seal to the list of varnishes to try. It's a poly that also gives the wood a nice look.

   Paul

4. 
   PeteBradley | Dec 09, 2003 09:11pm | #6

   I built a tiger maple step stool a little while ago that I needed to have a near-indestructible finish without looking plastic-y. I finished it with top coats of Arm-R-Seal gloss urethane wiping varnish that I rubbed down to a satin shine with some 4F Pumice. Really easy to use, and incredibly durable so far. If you have a Woodcraft store in your area, they carry it. I think it's readily available elsewhere too.

   Pete

1. 
   Gretchen | Dec 09, 2003 09:15pm | #7

    needed to have a near-indestructible finish without looking plastic-y.

   I really do wonder why polyurethane is EVER the only thing many look to as a finish.  There is and always has been NON-poly varnish which gives wonderful warm depth to the finish and the wood.Gretchen

1. 
   Paul_Snyder | Dec 10, 2003 01:46am | #8

   I think it's because poly is the most durable of the varnishes. The resins in poly have the best resistance to water, heat, chemicals, and scratching.

   Poly has a reputation for looking like plastic, but that is dependant on the brand and application technique. The Arm-R-Seal is a nice looking polyurethane as are a number of other brands. Arm-R-Seal is the product that David Marks uses on his show when he talks about applying a "tung oil" finish. Some brands use a cheaper type of resin (there are a multitude of resins manufacturers can choose) that do look bad compared to other, more expensive types. And if the inexpensive poly finish is built up very thick, it will look like plastic. Jeff Jewitt mentions this in this article - Selecting a Finish - in the fifth paragraph under the heading, "The type of finish will notably affect the look of the wood."

   Since all varnishes are cross-linking finishes, they're all equally difficult to strip if that's an issue. Poly is no more difficult than other varnishes.

   So why not use poly when you want or need the durability? Just use a good brand.

   Paul

1. 
   Gretchen | Dec 10, 2003 07:28am | #10

   So why not use poly when you want or need the durability? Just use a good brand.

   My point would be--you can get the durability without the plasticity-look.  Poly actually scratches more than a non-poly varnish.  It   IS   that folks just don't realize that there is an option that is beautiful.  BEcause of marketability--and forums that don't tell you about other options--like   "varnish" without polyurethanes.Gretchen

2. 
   SawdustRay | Dec 17, 2003 10:28pm | #11

   Do you have a non-poly varnish you recommend.  The only varnish I've used is Bartley's gel varnish.  I've also just finished a piece out of walnut and alder and have three coats of tung oil on it.  How easy is a varnish to repair or touch-up?

   Thanks

1. 
   Gretchen | Dec 17, 2003 10:30pm | #12

   Pratt & Lambert or McCloskey's. Gel varnish is poly I'd be pretty sure. I use the wipe-on method.  I haven't had occasion to need to repair so can't speak with experience.Gretchen

2. 
   Tao | Dec 18, 2003 05:23pm | #13

   Pratt & Lambert's 38 is a great interior varnish and has been for decades, as are McCloskey's products.  Behlen / Mohawk also make some really good varnishes. 

   If you're anywhere near Kansas City I have a few gallons of P&L 38 left over from a large job that I'd let go cheap, since they are just taking up space in my finishing room.

   Michael R.

1. 
   Scooter456 | Dec 18, 2003 07:08pm | #14

   Your question is a good one, and it demonstrates that you need some more education on finishes.  Buy a good book(s) on the subject and try some other finishes.  I am not being critical, please, but merely suggesting that you educate yourself.

   Combination finishes are OK, and there are instances where they are desireable indeed necessary.  One example is Shellac, which I use as a sealer coat between water based stain and other finishes. But I know of no practical reason why one would finish a piece with oil, then top it with poly.  Makes no sense to me.

   If you like the way oil looks and feels and its ease of application, then use oil.  Top it with 2-3 coats of a good wax.  Carnuba is the hardest.   That is what I do with your wonderfull piece.  I would not cover up that oil with a mess of poly.

   Poly is a great finish too.  It is the single best finish for water but as noted it scratches and I will add it is impossible to repair and can be dificult to apply (it streaks, there are brush marks and puddles if you are not careful).  If you like the protection of poly and apply it without incident, then use it over your stain, not oil.  Poly is best applied using very thinned out coats like 50-50 with thinner, and wiped down.  However, I have used a full strength coat of poly over a FLAT HORIZONTAL surface but one has to be very carefull  and keep the brush on the table and resist the temptation to paint it on the surface.

   So, try some wax on your coffee table.  Your oil finish is fine.  If it messes up, it is one of the easiest finishes to repair, just a bit of sandpaper and more oil.  You did it right.

   Kelsey

2. 
   VeniciaL | Dec 18, 2003 11:56pm | #15

   Well,

   This just gets more and more interesting.

   KDo has some good points. May I ask just what you actually used to apply to your piece? I know you said you used tung oil. But what actual product? Was it really just pure tung oil? Most preparations that call themselves tung oil are really boiled linseed oil! And they actually contain some varnish too!

   If your finish was an oil/varnish preparation, I recommend applying several more coats, with either steel wool or 400 grit as the applicator, wiping as usual as the last step, as this will build up a better varnish film (although still quite thin). The look will still be a close to the surface finish, but it will have more durability.

   If you actually used pure tung oil, I still recommend going over it with a product that is an oil/varnish combination, or using a wiping varnish (just dilute any varnish 50-50 with solvent), making sure to wipe off any excess. You will have a kind of hybrid, thin-film finish without any "plastic" look and better protection than oil alone (though not as robust as a thick-film varnish).

   VL

3. 
   SawdustRay | Dec 19, 2003 02:08am | #16

   Thanks for the offer.  I'm in Houston, TX so I can't take you up on it.