Replies

1. 
   stantheman | May 14, 2009 03:18am | #1

   jv123

   Not an expert, but what is the point of the japan drier?  Normal use of that is max of 2-4 ounces per gallon of paint/varnish.  You are way beyond that.  That would be my first suspect.  You should get  more input shortly when the experts jump in.

2. 
   SteveSchoene | May 14, 2009 03:50am | #2

   You have an oil/varnish mix--perhaps.  Proper application calls for you to apply, let penetrate, and then wipe thoroughly off.  It should never build a surface film.  In principle the film will be soft, especially since you have used a spar varnish for the varnish component.  I say perhaps, because so many time people confuse Tung Oil Finish, which can be a varnish or an oil/varnish mix, with pure tung oil.   

   The hazy, crazed appearance likely comes from having 14% japan drier, quite a high proportion. This may have hardened the finish so much as to make it brittle.  (The original article in FWW "Hot Rod Your Varnish" was corrected to give equal amounts of oil and varnish, with just under 10% japan drier.) The manufacturer's instructions for the Japan driers suggerts adding up to 6%.  The real problem with adding japan drier, especially in such large amounts is that you generally don't know what metal compound is in it, and how it complements the driers chosen by the manufacturer of the varnish. 

   Some people, includidng the author of the article, have gotten OK results from the articles formulation, apparently, but when the chemistry isn't really understood, it becomes very uncertain.  For example, I believe the original "recipe" used an soya/alkyd varnish, not a spar varnish.  Pratt & Lambert 38. 

   Personally, I believe there was really no reason for all the creativity.  Take any good alkyd varnish, add thinner to give the desired working consistency, and wipe on a number of this coats.  It will be more water resistant, sufficiently flexible, and quite durable.  So I would strip again, and get a wiping varnish or make one by adding thinner. 

   The article was discussed, with some heat, in thread 41228.1. back in April, 2008.

    

   
   

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   Edited 5/13/2009 8:52 pm ET by SteveSchoene

1. 
   jv123 | May 14, 2009 04:14am | #3

   A few things to clarify.* I had used this same mix described in my original post on the underside of the table - as a dry run.... It worked fine with the same proportion of Japan Drier.* When I re-started the 2nd time on the top side of the table (as described above), I flooded the surface for 20 minutes with the oil/varnish mix, then sanded in and wiped off.* Then, I thought I would avoid the same problem I had experienced before by putting over that topcoats of Minwax Wipe ON Poly. The entire surface dried to an awful hazy appearance, and after 12 hours, was not hardened, and when sanded came off in little waxy blobs. * I again took all of this 2nd coat off, and then tried with the oil/varnish mix again. That's when the spotty/hazy surface shown in the picture appeared...which is where I am now.* All of the finish has been applied using wipe-on method.So...my suspicion is that I have some kind of contamination problem...no? Shall I strip off and put on a coat of de-waxed shellac? I want to avoid that, since I'd like it to soak in and get as much of an "in the wood" feel as possible.....Any further advice much appreciated. I'm stumped.JVEdited 5/13/2009 9:14 pm ET by jv123

   Edited 5/13/2009 9:15 pm ET by jv123

1. 
   saschafer | May 14, 2009 04:50am | #4

   The "crazed, hazy" look you mention in your first post can almost be considered to be the "signature" of too much Japan drier. The crazing occurs because the outer surface of the finish dries too fast, while the finish underneath is still loaded with solvent and is still fluid.I think what's happening is that you're sitting right on the ragged edge of having so much drier that it's a toss-up whether or not the finish film will cure properly. If conditions drift a little bit in one direction (a little cooler, maybe more humid), the finish will end up looking okay, but if they drift a little bit in the other direction (a little warmer, maybe less humid), the finish will break up.What led you to use that much Japan drier in the first place? Were you following a published recipe?-Steve

1. 
   jv123 | May 14, 2009 06:35am | #5

   I was trying a variation on the "Hot rod varnish". Again - it had worked fine when I experimented with it on the bottom of the table!I just re-coated with thinned out spar-varnish, wiped on, and it looks a bit better as it is drying.... I'll check in the morning ot see how it turned out.Thanks for your help.

2. 
   SteveSchoene | May 14, 2009 08:15am | #6

   Polyurethane varnish is known for adhesion problems.   You may have had incompatibilities between the polyurethane varnish beling placed over a "non-standard" finish mix. 

   Using just thinned spar varnish may well give you an acceptable finish.  It's not my first choice for furniture because of it's softness.  But, it won't give a particularly "in the wood" finish unless you wipe it off rather quickly after application--something that is very hard to do because varnish starts to get tacky pretty quickly. 

   I will come back to the point that the "Hot Rod Your Varnish" article may be overly "Iffy" to use, especially if there are any variations from a very specific formula that happened to work. 

   Edited 5/14/2009 1:19 am ET by SteveSchoene

1. 
   jv123 | May 14, 2009 03:27pm | #7

   Thanks again for the insight. I did recoat with thinned spar varnish (I had used this on an old farm table we had been using as our primary dining surface...to good results), and although some of the strange surface showed through, I think it will disappear once I level it with sandpaper (using mineral spirits as a lubricant), and another couple thin coats. RE: in the wood look...I tried to get an "in the wood" look on the bottom of the table when I was experimenting with the "hot rod mix", but when I tested how water resistant it was, it still gave me slight rings when leaving a moist glass on it. I am now resigned to having a tabletop surface that has a bit of a film finish on top, since I don't want to have to treat it with kid gloves. It will be a built-in, and will get a lot of abuse.Is there an "in the wood" type finish that would give me the kind of moisture protection tat spar varnish would? I think the answer is no - but would be tempted to start over again if there is a magic formula out there.(Sidenote: I actually had spoken with the grandson of George Nakashima, who works at the hardwood dealer near me, and he said that he uses a formulation that gives a nice in the wood look, and does have these properties. But, still eludes me...).Thanks again.JV

1. 
   Gretchen | May 14, 2009 04:41pm | #8

   Spar varnish is already a long oil varnish and you have added more oil plus drier.  Maybe it is just me, but I think paint companies probably try real hard to get mixtures put together that they can count on for adhesion, look, etc.--at least top line companies like Pratt and Lambert, Waterlox, etx.

   Strip it, make a mix of non-poly varnish and thinner for a wiping varnish and use that. You will have a beautiful "in the wood" finish.

   Your "experiment" on the bottom for water resistance could have a whole lot more to do with the mixture AND not enough finish than that it wouldn't be water resistant if you did it correctly.

   I use spar varnish for much of my wiping varnish and I will guarantee you that you can put a wet glass down on it and there will be no ring--IF you have a sufficient film finish on the piece. And the same for regular (not spar) varnish.

   Gretchen

   Edited 5/14/2009 9:45 am ET by Gretchen

2. 
   chaim | May 15, 2009 08:18am | #9

   You can use almost any building top coat and knock it back to a satin almost dull look!

   Rubbing out (after the finish is cured) with a combo of sanding and rubbing with steel wool and paste wax can yield a nice flat look and give an almost "in the wood" look. It works especially well with open grained woods.

   Chaim 

3. 
   davcefai | May 15, 2009 08:30am | #10

   Could it be that the last coat could not penetrate the wood because the previous coats had sealed it completely?

   You would then have the situation where the coat starts to skin over while there is still solvent in the mass.

1. 
   Shoemaker1 | May 16, 2009 04:14pm | #11

   A good friend of mine managed a paint store for years. He explained that to much drier will give an uneven sheen. He warned every one who bought it not to over do it.

1. 
   HowardAcheson | May 16, 2009 05:42pm | #12

   You are right. Too much drier adversely affects a finish.My thought is that the finish manufacturer knows much more about the product and how to prepare it than the buyer. Other than perhaps thinning it (and you don't want to thin waterborne), it should be applied as is. After all, the manufacturer wants the user to be successful using the product so they will do everything they can to make it "user friendly".Making "home brews" can be a prescription for problems unless one really knows what they are doing.Howie.........

1. 
   Gretchen | May 16, 2009 06:07pm | #13

   And probably even if it seems "OK" now,  you don't know what the finish will "be" in 10 years. The "more is better" phenomenon doesn't always work with chemicals!  ;o)Gretchen

1. 
   jv123 | May 16, 2009 06:16pm | #14

   Sage advice, all...

   I'm away for a few days, and will let you know how I fare. I am now resigned to strip it and start again.

   I have had a good bit of experience with finishes (and woodworking in general) and every time I face such a thing, I feel as if I'm humbled somehow...

   Again, thanks for the help.

   JV

2. 
   Gretchen | May 16, 2009 08:06pm | #15

   When you strip it be SURE to remove all vestiges of the stripper, or you will have something that looks much like what you have now.  It really should be very easy to strip this clear finish so at least that won't be so bad.Gretchen

3. 
   jv123 | May 16, 2009 09:52pm | #16

   Thank you! What should I use to remove all traces of the stripper? Use a wash coat of shellac to be sure?

4. 
   Gretchen | May 16, 2009 10:36pm | #17

   No,no. Just wash it off with mineral spirits on lots of rags/paper towels. It won't be hard, as I said, since this is a clear finish--and not much of it, at that.  ;o)Gretchen