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Russ Filtz
01-04-2008, 7:39 AM
I've had some flake shellac for several years. Tried to dissolve some in DNA, but it doesn't want to go! Didn't use any specific mixture, put some flake in and covered it about double height with DNA (about 2:1 DNA by volume). Has dissolved some, but there's still a lot left in the bottom. Do I need more DNA or is the flake bad? It's been setting for about 3-days with occasional shakes, but it's been cool in the garage, between 40-70.

Jim Becker
01-04-2008, 9:11 AM
I've had that happen even with new flakes. My solution (literally) was to use an old blade-type coffee grinder that was lying about to pulverize the shellac flakes. They now dissolve faster and more completely. Raising the temperature should help you too...stuff goes into solution easier at higher temps. Since it's in a covered container, just bring it into the house. My understanding is that flakes should last more or less indefinitely.

Roy Hatch
01-04-2008, 9:13 AM
Russ, When I have heard of "bad shellac" the problem was that it wouldn't dry properly after application.

The proportions you describe seem reasonable so my suggestion is to stir it to see if that will help. I would also be tempted to apply some of your solution to determine if it will dry. If it won't dry, then it's trash.

Some suggest breaking flakes into a powder (as in a coffee mill) to speed the process, although I have never found this necessary.

Roy

Dennis Peacock
01-04-2008, 12:55 PM
Roy and Jim have you covered pretty well with info. It will help to bring the solution inside to warm for 24 hours if that's possible. As long as your DNA is fairly fresh, you should not have any problems with the shellac.

Rob Amadon
01-04-2008, 6:12 PM
Flakes can go bad if they are kept in a warm/hot humid place. Last week when I dissolved some that I needed in a hurry, I put the entire container in the sink with hot water in it. Now my hot water is quite hot, but I changed the water twice in a couple of hours and a quart of 3# cut was completely dissolved in 3 Hours.

Rob

Russ Filtz
01-08-2008, 7:36 AM
Brought it in, but doesn't seem to have any effect. Lots of undissolved flake at the bottom. Rubbed the solution on some wood and it seems to cure fine. Maybe I'll try to decant the dissolved stuff and try some new DNA and see if any more dissolves.

Steven Wilson
01-08-2008, 10:50 AM
3-days and you're worried? It can take up to a weak for it to dissolve. Just take a wooden stick and mix it up twice a day and shake the bottle a couple of times a day. It will evenentually dissolve. In the future use a coffee grinder to grind the flakes, mix with DNA, shake frequently and it will disolve within a few days.

Russ Filtz
01-08-2008, 1:41 PM
At this point it's been at least a week if not more. The remaining flake has been pretty much stable (undissolved) for 4-5 days! The flake is probably 4 yrs old, so may be time to replace!

Rob Amadon
01-08-2008, 2:28 PM
Russ,

How were the flakes stored? If you keep them in a cool dry place they can last almost indefinitely. If they are kept in a warm and/or humid place then they may very well be past their prime.

Some shellac is past its prime when you buy it. Shellac imported directly from India (i.e. not processed in Germany) sometimes has a hot humid ride on a cargo ship on their way to the U.S. that will degrade them.

Rob

Russ Filtz
01-09-2008, 7:53 AM
I used to store it inside, but the last year or so I think it's been in my Florida garage! Time to "cut" my losses and get new!