Replies

1. 
   SteveSchoene | Mar 30, 2008 06:08am | #1

   Moisture isn't the big problem for shellac in bathrooms, its household cleaners and the like. For what you are looking for I would use an oil based varnish, and in particular one which is alkyd resin with soya.  While not completely water clear, this would be quite a bit lighter than a linseed oil/alkyd or tung/phenolic varnish.  A good one is Pratt & Lambert 38.  If you are more comfortable with a wiping varnish you can simply thin the P&L varnish to wiping consistency. 

1. 
   labatt50 | Mar 30, 2008 06:45am | #2

   Thanks for suggestion! Let me ask you this, if moisture won't be the major problem, can i just build up the existing coats of shellac. Right now the cabinets just look like it's a very thin coat(s).

   Any other idea's?

1. 
   SteveSchoene | Mar 30, 2008 05:24pm | #3

   Welll you could, but bathrooms are, along with kitchens, places that people really want to clean periodically.  If you can assure that no one will ever want to spray cleaners on the cabinet you might get away with it, but I sure wouldn't want to risk it.  Having a situation where you have to lay down ultimatims about housekeeping isn't my idea of having a pleasant life.  The additional color from the varnish will be pretty subtle.  Less that if the first coat directly on the wood were the varnish. 

2. 
   systembuilder | Mar 31, 2008 01:53am | #12

   Steve,

   I may try this varnish for a future project. The P&L website has a product data sheet and calls this product "hard and flexible"??? Can you get both qualities at the same time? Can you rub out a finish that is "flexible?"

   Dan

1. 
   SteveSchoene | Mar 31, 2008 02:04am | #13

   Even P&L isn't immune to the triumphs of marketing.  It is hard relative to polyurethane varnish and rubs out better than they do.  It is flexible, but that's relative to lacquer or shellac which rub out extrodinarily well, so teh P&L  will be a little more difficult than those, but still pretty good.  

2. 
   Joe Sullivan | Mar 30, 2008 05:59pm | #4

   I agree with Steve, to a point. Moisture isn't a major problem AS LONG AS you have good vents and fans. Builder standard f*rt fans are not adequate at all. There is an air exchange ratio needed in bathrooms. Yoo size the fan to the bathroom. The moist air should be vented to the outside, and not to the attic or crawl space. You can get this information over on the Breaktime forum, or other places on line.

   FWIW, your properly-sized fan should remain on through the duration of any shower or bath, and for at least 20 minuted thereafter. How big is the difference? One of our baths used to always have condensation streaks on the wall. With a new fan, we get very little condensation, even on the mirror -- and even after a 25 minute teenager-shower.

   That said, shellac is a good humidity barrier, of you have two or three coats. However, Steve is absolutely right about the cleaners. I'd probably apply another coat of shellac, followed by the varnish Steve recommended. The varnish is very important.

   Joe

3. 
   HowardAcheson | Mar 30, 2008 06:08pm | #5

   Are you sure the current finish is shellac? Did you apply the shellac? Was it standard shellac or dewaxed shellac?

   Howie.........
1. 
   labatt50 | Mar 31, 2008 12:00am | #9

   The original finish was bullseye shellac (clear)

1. 
   user-83153 | Mar 31, 2008 01:38am | #11

   labatt,

   Bullseye shellac has wax in it. So that should rule out polyurethane and waterborne finish. Which would be fine by me as I don't generally use either on furniture or cabinets. Putting a coat of de-waxed shellac over the waxy stuff is risky because shellac is an evaporative finish and each coat melts and mixes with the one below it. So while you may have less waxy shellac, it still will probably have wax on the surface.

   I think that Steve S.'s suggestion is still the way to go, unless you have the proper facilities to spray conversion varnish, or one of the catalyzed finishes. They have very strong and flammable chemicals and are not designed to be sprayed by the weekend finisher. Use an alkyd resin/soya oil varnish, such as the P&L #38 mentioned earlier or Cabot Oil Varnish (not the poly!). They will darken the cherry somewhat, but they are pretty color stable and the cherry will darken on it's own anyway no matter what you do.

   I love shellac as a finish, but not in this situation. In addition to the ammonia based cleaners you have to worry about fingernail polish and polish remover, and hairspray. All of those things will damage shellac quickly and are very common in the bathroom.

                                Rob

2. 
   HowardAcheson | Mar 31, 2008 06:07am | #17

   >> The original finish was bullseye shellac (clear)If that's the case, the shellac is not dewaxed. That means you should not apply a poly varnish on top of it. Nor should you use a waterborne finish.I would suggest you apply a couple of coats of a non-poly varnish like Waterlox or, if you want a lighter color, Pratt & Lambert 38.Howie.........

4. 
   jackplane | Mar 30, 2008 06:34pm | #6

   Shellac alone is NOT much of a moisture barrier. Especially in a bathroom, it will turn white with enough exposure to water/water vapor. As was noted, a polyurethane works well as a topcoat.

   Expert since 10 am.

   
   

   ---

   Edited 3/30/2008 12:52 pm ET by jackplane

5. 
   frenchy | Mar 30, 2008 06:51pm | #7

   labbatt50

     I differ from Steve.. You see many cleaners won't affect shellac at all.. those without an ammonia base for example..

     Steve seems to feel that only ammonia based cleaners can ever be used to clean things..

     If you must use Ammonia based cleaner than Steve is correct,  however if you buy cleaners that aren't ammonia based then shellac will tolerate those well.

      What are your painting skills like?   Can you do brush mark free work for example?  what sort of finish are you going for?  High gloss, deep shine, semi gloss,satin finish? 

    

    

1. 
   Rich14 | Mar 30, 2008 11:04pm | #8

   How does anyone know what kind of cleaner MIGHT get used in a bathroom? What are you going to do, post a warning on the cabinets? Why all the speculation? How do you know the user of a cleaner knows what's in it?And the chances of alcohol getting on bathroom surfaces is very high. Then the shellac WILL be damaged, either to a very slight degree or severely, depending on the length of contact before it is removed, but damage WILL occur.Shellac is NOT the finish to be the receiver of the kinds of things that will get on bathroom surfaces. It is water resistant to a degree far better than most assume, but it WILL fail in a bathroom environment, guar-ON-teed.Before any final surface is applied to the existing finish, it IS important to know if it actually IS shellac, and if so, does it contain wax. If it does, a coat of dewaxed shellac should be applied to seal the waxed stuff, which may shed other finishes otherwise. If it is already a dewaxed shellac, then just about any other finish can be applied over.I suggest going over to the Breaktime forum and ask for advice where people who do this kind of thing for a living hang out. I'm betting the finish that will be recommended is catalyzed varnish, conversion varnish or catalyzed lacquer. ANY kind of varnish is a better bet than shellac in a bathroom.I'm a big fan of CAB Acrylic lacquer, but it will fare no better than ordinary Nitrocellulose in bathroom/kitchen conditions - that is, poorly, compared to the varnishes or catalyzed lacquer.Rich

   Edited 3/30/2008 4:22 pm ET by Rich14

2. 
   labatt50 | Mar 31, 2008 12:04am | #10

   What are your painting skills like?   Can you do brush mark free work for example?  what sort of finish are you going for?  High gloss, deep shine, semi gloss,satin finish? 

   Frenchy,

   I can do brush mark free work (but I'm not a great finish guy!). the desired finish is a clear (untinted) semi gloss.

   Thanks,

1. 
   frenchy | Mar 31, 2008 02:41am | #14

   labatt50

     In that case I'd use a tradtional finish such as a varnish directly over the shellac.  I'd take the doors off because it's faster than taping off the hinges and hardware. Plus that way I can paint the doors laying flat.  

1. 
   labatt50 | Mar 31, 2008 03:25am | #16

   Thanks all,

   I will go with the Pratt & Lambert 38 varnish.

   Any suggestions for application of this will be well noted.

3. 
   SteveSchoene | Mar 31, 2008 02:57am | #15

   Ammonia is not the only things in cleaners that can affect shellac.  Other alkaline solutions can also dissolve shellac, and lots of cleaners are rather basic.  Formula 409 has a pH of 10.5 and Fantastic Spray Cleaner has a pH of 12.1. 

1. 
   blewcrowe | Mar 31, 2008 08:05pm | #20

   Now, why confuse these folks with the facts? <g>

6. 
   woodshaves | Mar 31, 2008 09:46am | #18

   We need to remember that there is also perfume, nail polish remover, some hair products, after shave and more, all capable of damaging shellac around bathroom cabinets. Another reason to coat with a more water resistant topcoat is that ironically, shellac surpasses moisture vapor prevention (to penetrate into wood fibers, US Forest Lab. testing), exceeding poly, alkyd and phenolic varnish as well as celluloce nitrate-based lacquers, BUT, shellac ability to withstand water decreaseswith the age of the film application.

1. 
   Joe Sullivan | Mar 31, 2008 05:43pm | #19

   Agree. My point earlier was that shellac is a good vapor barrier, according to empirical tests. However, bathrooms ave all kinds of stuff that gets spilled, to say nothing of cleaners. Take, for instance, the night my wife unknowingly knocked over a bottle of Chanel #5 perfume. If that had sat on shellac all night, goodbye shellac. True, the shellac could be repaired, but the wood would have been stained, too.The OP can put a coat of Zinsser Seal Coat over the Bullseye, and thereafter apply whatever varnish he chooses; the varnish is important, though.