AAARRRGGGHHHH!!!!

[DarwinStrings]

Bloody shellac won't mix, grrrr. Yes I have 100% denatured from "Shines" always shut tight, worked okay the first time, maybe water gets in through the plastic bottle. Frustrating stuff as am doing up a 1930's Italian mandolin for a guy and need shellac to work, might just have to try a new bottle of metho from bunnies cause am a bit tired of getting this stuff from down south. Frustration vented.

[charangohabsburg]

Is the bloody shellac blond? Highly discolored shellac has difficulties to dissolve when it was stored too long. Just let it sit in the alcohol for several days, maybe up to a week or two, stir it up once or twice a day, and most of it will dissolve. Then let it sit for a day more, decant the good part and ditch the last tiny bit that still contains undissolved pieces. Of course the reason of not dissolving well could also be highly hydrated alcohol, but I think you don't really need extremely pure 97%-or-so stuff. In the past I have used denatured alcohol from bottles I had opened over an year ago, and it was still good to dissolve shellac.

[Allen]

It's most probably the shellac itself Jim. Blonde shellac has a very short shelf life I found out the hard way. Especially in our tropical heat. They will go off very, very quickly.

I've had a few orders that just worked brilliant as soon as I get them, and even a month later making a new batch they don't really want to dissolve, and even if I can manage to get some to mix, the resulting batch never wants to harden up.

Had a talk with Jeff Hannah and he put me straight. Buy in small quantities. Always keep the dry flake/powder in the fridge in a sealed up container. Make small batches that will get used up in about a week.

Once I started doing that, everything is working out as expected.

[Kev3]

Tend to agree with Allen and Markus. Shellac (flakes etc) does have a shelf life and keeping sealed in a fridge is the best way to try and extend it.
As for the 100% ethanol, well, that is best - but I've had just as good success with decent grade meth'. Ethanol doesn't want to stay at 100%, it is extremely hydrophilic - it will absorb water every time you open it and will over time get in there no matter what you do (unless kept in vacuum all the time ).
We use it for dehydrating samples and only way to keep it at or close to 100% is to include a desiccant in the bottle with a greater love for water.

[peter.coombe]

Yep, chuck the shellac and get a new batch. Shellac does have a shelf life, the blond-er it is the shorter the shelf life.

Peter

[DarwinStrings]

Okay thanks all, will leave it a bit longer Markus and see what happens. Yep guys it is the pure blonde stuff. I do have a newer batch that I have not opened so I will give that a try. Looks like this bloke might not get his mandolin before he leaves for a month OS if my other batch fails, hope he is not too put out.

[DarwinStrings]

Saved by the ANZLFers. The second batch I have is mixing, thanks again guys.

[needsmorecowbel]

That's why my blonde shellac wouldn't dissolve properly. Thanks for the tips guys!

[kiwigeo]

Blondes are always trouble

[DarwinStrings]

Looks like my last post was premature, I thought it was mixing at first but it ain't. Seem there are some differing views on it.

THESE GUYS used old knarly dewaxed fairly blonde looking stuff that they had laying around and they reckon it is fine. So I start to think maybe my alcohol has too much water which leads me to search Darwin to see what I can get. The best I can do is buy 12 x 1 litre bottles of "Bio Flame" a diggers product at 99% for $85 or I can buy 200 litres of 100% (because it is sitting out the back of a hardware and they are not sure why they have it) for $100, not sure I have room for a 44 gallon drum of Ethanol (party perhaps?).

Interestingly when I phoned "Diggers" they explained than Methylated spirits is not methylated anymore apparently cause methyl alcohol is too poisonous. So Diggers Metho is 95% ethanol with the rest being water and what he called "bitterants". The Diggers "Bio Flame" is 99% ethanol with 1% water and crap.

Shame about the post situation or we could split the 44 gallon of 100% stuff down to 50c a litre.

I also bought some "orange shellac" at bunnies and that will mix with diggers metho but it is pretty dark looking (more dark brown than orange looking) still good enough for a seal coat though.

Also I found some "golden" somethingorother shellac at a paint shop which I will go and buy to see how that one goes.

[auscab]

I was reading an old book the other day on Pattern making , the wooded type made for doing castings for machinery in cast iron or other metals . The pattern makers used to use shellac to seal patterns and colour different parts. The author was writing of how the shellac should be kept in a ceramic jar , not metal, and the problem of the shellac sometimes becoming discoloured. The remedy for the problem was to add Oxalic acid to the mixed shellac . That was first time I had heard of that . It said not to do it too much because it weakens it. the bleached or blondes I have had always have been weaker than normal flake or button orange. I don't know if it will lighten your shellac Jim ?
Any old shellac I have had that wont dissolve I gave up on and threw out , It may be good for adding colours to with heat for filling holes with shellac ?

[peter.coombe]

I still suspect the shellac. I once ordered some of the blondest dewaxed shellac from LMI and only half would dissolve in metho soon after it arrived in the post, so the shelf life is really short. The next darker blonde shellac was fine. The next darkest blonde shellac will last several years before it starts to not dissolve overnight. You can get some of the stubborn stuff to dissolve by heating the metho in a hot pot of water, but even that did not work with the super blonde stuff. Apparently the really blonde shellac is bleached and the bleaching process reduces the shelf life. If I were you I would get some dewaxed blonde shellac that has a bit more colour in it. My stuff would be at least 3 years old now and is still going fine and will probably still be fine for a few more years. I have never used anything but Diggers Metho since it always worked unless the shellac was really old.

[DarwinStrings]

I keep it in glass Rob and the dark stuff from bunnies came in a plastic jar. I think the pure blonde will end up in the bin.

Nice one Peter, that is the conclusion I am coming to on the web too, just don't bother with the pure blonde stuff and get some other de-waxed. I just picked up 100g of a "golden" one no where near as dark as the bunnies one and looks, so far like it is mixing better than the blonde. This Golden one doesn't say de-waxed so looks like I will have to order via mail from down south in the end. Oh and by the way this golden stuff I bought looks like it's been on the shelf in a plastic bag for 20 years but it was only $7 so thought I'd have a look just for the experience.

[Allen]

I'd bet it was the shellac as well.

I had bought 1/2 kilo of de-waxed blonde and used some right away. Worked perfect. Just stored in the plastic bag it came in under my workbench in the shed. Didn't know any better at the time.

About 6 weeks later I needed some more and mixed up my standard batch. Whereas the first batch dissolved within about 10 minutes, this batch showed what looked like undissolved particles even after 1 hour. So I strained it and tossed the filter out, leaving me what appeared to be shellac ready to use. I only applied it to the inside of instruments, so didn't worry too much more about it.

A couple of weeks later I made up another batch and the same thing, except even more didn't seem to want to dissolve. But this time I used it on the outside of an instrument. One I was French Polishing.

It went on sort of all right, but just wouldn't harden up the way I thought it should. However I persevered.

2 months later that finish would still take a thumb print within seconds, so I got the shits with it and stripped it all back and sprayed it with lacquer.

Tried one more batch and this time virtually none of the shellac would dissolve. Into the bin it went and I started to do some research.

BTW. I use metho from the local chemical supply. They say it's 95% pure. It works just fine when the shellac is new.

[DarwinStrings]

Was your's "super blonde"/ "white" Allen or was it just "blonde"?

[Allen]

Super Blonde De-Waxed.

[charangohabsburg]

It seems I have never come across such super blonde stuff. The "blonde" shellac I normally use (flakes) has a nice golden hue. I am now at the last bit of a batch I bought back in 2008 (!) and it dissolves completely in about 2½ days (vs. 1 night when it was new). Later I also bought some "white" shellac (ground) which dissolved very quickly when it was new, but yields a solution of a rather muddy colour. But when it was about 1 year old it took a whole week to dissolve "completely", leaving some gravel on the bottom of the jar. This is what I referred to earlier in this thread. According to Allen's report my "white" shellac is obviously still not "super blonde" (glad I never found some).

[Allen]

Your white shellac sounds similar to what I'm calling super blonde. It's ground up to a fine powder. Looks like fine sugar.

[charangohabsburg]

Not sure it's the same, it is only called "white", the actual colour is what you see in the picture.

Having gotten curious if what I still have would dissolve at all (bought it in 2011) I gave it a try using denatured ethanol from a half-empty bottle I bought two years ago. Much to my surprise, after 2 hours most of it was dissolved, and you can see in the picture how it looked like another 2 hours later.

I am wondering now why I had a slight problem with the same batch about two years ago, but not now. Maybe it is because now I only used a bit from the clumped stuff on top in the big jar, maybe it is the fine powder on the bottom that turns bad because of the greater surface/volume prone to oxidization. During the first half year I left it the paper bag it came in and stored it in the cellar (RH 60% and more, 12-20°C), after that I put it in this jar and then always stored it at room temperature (20°C, except during 2 months in summer when it gets up to 30°C), RH normally 40% and less, I don't recall how it was when I closed the jar last time.

[DarwinStrings]

The first i bought was super blonde and the second was white but they look exactly the same as a powder and in solution. Even after a week being agitated during the day they still form two separate layers, clear at the top muddy at the bottom and that is at a 1lb cut so no matter how much I hope, I'd say they are cactus.

So I will order more but that leaves me with the question, do I buy in Australia where turn over might be low or buy from a overseas mob which may have a higher turn over, I will buy some blonde and something darker both de-waxed. The mando owner seems fine with the delay after I explained.