Shellac is perma-gelatin

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I'm trying to use Shellac flakes for the second time and am having some trouble. The first time I used it they dissovled after about three days without much fuss, but this go-round I've got a big blob of gelatin at the bottom of my bottle that I can't get to dissolve. Here are the facts of the case:
* Bought blonde dewaxed shellac from Woodcraft on Thursday * About an hour later, I smashed it to smithereens with a hammer and added it to brand new alcohol (in a well sealed plastic bottle, also from Woodcraft) in a 2# cut * I tried adding it to the alcohol slowly and letting it dissolve, but it just sat at the bottom and stared at me desipte repeated stirrings, so I dumped it all in. * The bottle is a very well sealed glass jar with a rubber grommet and a metal latch - no chance of moisture getting in that I can see. * I put the bottle in a bath of warm water to speed the reaction * Come back four days later, and there's goopy shellac gelatin on the bottom, maybe about a quarter of the original volume, undissolved. I've spent the last couple hours breaking it up, warming it, shaking it, and repeating, and it's still just gelatin--the undissolved portion hasn't changed much.
Is this shellac no good? Should I return it? Did I blow it in step 3 by being impatient? I still have another bottle of flakes in the fride and I don't want to screw up another batch.
Thanks, George
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Go to Home Depot and buy some Bulls Eye premixed.
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oh, that was very helpful
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The reason for my flippant response was I used to be a mix your own guy myself. Once I started using the Bulls Eye from HD, I never looked back. HD wouldn't keep it on the shelf if it sat there for 6 months, they wouldn't carry it, and some locations don't.
They (Zinser) claim they have a longer shelf life due to specific additives or processes. The longest I've kept 1/2 a can was a year and it was fine when I used it again. I've been through probably 10 gallon cans and have never had a bad experience with it. While mixing my own was about a 50/50 proposition.
My point was, mixing is a hassle. I know it seems kinda cool and is convenient. But I haven't found it to be a better solution then grabbing a quart from HD...personally
BW
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I'm steering clear of premixed because all the books agree that it goes bad in six months, and if the flakes I'm buying are possibly bad, I can't even imagine how bad the situation is at home depot. I need help to figure out if my current batch is salvageable and what I should do differently with my next batch.
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wrote:

Bullseye has a "born on" date, and promises a 3-year shelf life.
I've never tried to push it, but it's cheap enough.
Flakes can go bad, but mixed shellac WILL go bad. My understanding is that bad flakes are the result of too warm or damp a storage situation, but I've never had bad flakes.
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Well, that's certainly the easiest possible answer. I'll go to Lowes tomorrow as their web site says they carry it (no luck at HD). Now, what to do with the 4 pounds of flakes I have?
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D'oh...looks like it's not dewaxed! This furniture is too important to take chances with so I don't think I can live with that. Argh, why must everything be flawed?!
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What's not dewaxed? The Zinsser? If you want dewaxed Zinsser, buy the SealCoat sanding sealer. You _could_ decant/dewax the other, but that's an awful lot of hassle, IMHO.
If you got the flake at Woodcraft, what brand was it? I've gotten Hock and Liberon from them, retail. Both worked well for me, as does/did the Zinsser canned stuff.
If you thinned your mixed batch with more solvent, can you get more of the gel to disolve?
Patriarch
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snipped-for-privacy@gmail.com wrote:

To solve the wax problem, either use Seal Coat, or just de-wax it yourself. Seal Coat is a 2# cut, and it's dewaxed out of the can. (I've heard... Haven't used it.) The regular Bullseye stuff is a 3# cut.
If you're mixing down some 3# into a jar to make a 2# cut, say, then pour off some of the 3#, add a suitable amount of alkie-haul, and shake it all up. After it's mixed, let it sit a bit. Probably overnight should do it. You'll wind up with goopy yellow stuff at the bottom of the jar, and amber liquid on top. Pour off the amber liquid, and that's your dewaxed shellac.
Of course, having said all that, I didn't bother to decant the shellac I used on my chess box last year. (Wow, it has been over a year since I finished a project. :( ) It came out just fine.
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If your books all agree on that, you're reading the wrong books. Sorry, but there's simply no rule that always holds, here or anywhere. In general, shellac you mix, or premixed shellac, will go bad somewhere between 6 months and about 5 years. While it varies with the specific shellac, it primarily depends on the storage temperature. When I had a cold workshop, I mixed shellac and easily kept it for years, and never saw any go bad. A friend in a warmer climate (and heated workshop) got just under a year.
Further, the new Zinsser has demonstrated it will remain good for much longer than natural shellac. They sent me a test sample when it first came out, and it lived up to their claims. Only more recent books are aware of this.
Further, I use different shellac colors which I mix from flakes. These are stored in sealed container, in a refrigerator, and I've used some over 15 years old.
Finally, you may just have a bad batch of shellac. I don't know what cut you're trying to mix, or what type of alcohol, but if some stirring together with a pot of hot water doesn't do it then something's wrong with it. (I assume you're not trying for a 12# cut, of course.)
GerryG
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I mix my own in small batches, and I use the see it shake it method. I make in the morning, shake every time I can, and it's dissolved by afternoon.
Two things you can do to hurt your chances are decrease the surface area actually exposed to alcohol by making a bunch of small grains and allowing the to clump to form, and attempting a two or three pound cut direct, rather than adding flakes to a made one-pound. Try larger pieces and one-pound, to be enriched later.
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On 28 Dec 2004 11:16:18 -0800, " snipped-for-privacy@gmail.com"

Howdy,
I am confused by the very last phrase above ("in a 2# cut.")
How much shellac (by weight) do you have in how much alcohol (by volume)?
I suspect that you may just have more shellac than you can get into solution.
You may already be aware that 2# cut would mean two pounds of shellac in a gallon of alcohol.
Is that the ratio you actually have?
HTH,
--
Kenneth

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I followed the directions on the bag for a 2# cut; two quarts of alcohol for one pound of flakes.
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Why did you have to smash it with a hammer? Wasn't it flakes to begin with? If it was clumped up, there may have been something wrong with it (moisture?) to begin with.
Unheated, shellac does take a long time to dissolve, IME. Sometimes a couple days to become completely dissolved, with some intermediate shaking and stirring. But if it's still a gloppy mess after four days, that's not normal. Try heating it in a pan of hot -- not just warm but almost boiling -- water for an hour or two. I find that's the best way to dissolve it.
(As I'm sure you now, alcohol fumes and an open flame are a bad combination, so you want to do the heating with a hotplate or on an electric range, or boil the water and turn off the gas before putting the shellac in the pan.)
On 28 Dec 2004 11:16:18 -0800, " snipped-for-privacy@gmail.com"

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It was a little clumpy as flakes, which worried me, but I crushed it because that would increase the surface area. I've been keeping it in hot water all day and it's mostly dissolved, so the situation isn't quite as grim as I thought this morning, although I certainly won't dare use it until testing it.
I did see on person say that heating it up makes the final finish more brittle. But since only one person has said that, I'm choosing not to believe it for now :)
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Shellac has organic acid components. Over time, the acids react with alcohol and form esters --- which won't dry properly. I'd guess that heating the mixture would just speed up the esterification recation.
I'd suggest to just mix the flakes and alcohol and shake it occasionally. I'd should dissolve in a day. Also, have you considered the alcohol? Maybe it contains too much water. Try again with different alcohol and see if that works.
Joel Jacobson
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While I agree with your reasoning, it's a matter of degree. A few hours in a pot of hot (tap hot) water will really shorted the time for it to dissolve. I don't believe that will have a significant impact on the shellac. I believe you'd find Jewett and other finishing authors in agreement on this.
I also suggest you could add considerable water to the alcohol, and not see the problems he reports. (This is a very easy thing to try, if you disagree.) GerryG
On 29 Dec 2004 02:11:20 GMT, snipped-for-privacy@aol.com (Joeljcarver) wrote:

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    How about using Isopropyl Alcohal? This is supposed to be water free.
Ted the lerker
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On Sat, 01 Jan 2005 19:16:01 +0000, ted wrote:

Sure, if you can find anhydrous. Rubbing alcohol is 70% v/v iPrOH and the rest water. I've got some 91% iPrOH, but that's still 9% water. Not good.
Everclear and Hock flakes... some day.
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