Solvent for Shellac?

[Horaldic]

G'Day Folks

A quick question. A while ago I bought a bottle of low moisture content solvent to make up my shellac with. I'd had problems using commercial metho and thought it may have been due to the fact it can contain up to 20% water. It turned out that the quality of the finish was much better with this solvent.

The thing is, I can't remember what it was called and have lost the bottle somewhere. I have a friend with the same problem who wants some. Can anyone give me a pointer?

cheers

Horaldic

[Horaldic]

Answered my own question! "Redistilled ethanol" or "ethanol 95%", I knew I had it somewhere.

[ubeaut]

100% IMS (Industrial Methylated Spirits) also called Ethanol
or
95% IMS

Both should be available from any GOOD paint shop many Mitre 10 shops carry it or used to. Mostly sold in 4 litre bottles but occasionally in 1 litres.

If it isn't marked Industrial Methylated Spirits then it can legally have up to 42% water in it as Metho must be overproof which means it must be able to burn and it will burn with that much water in it. Not worth spit for use with shellac.

To test if Meths has water in it add a little turpentine to the bottle and shake. If it goes a slight milky colour it's got water,if it stays clear... No water.

[Rattrap]

Does it really make that much difference?
I chased around town to find some industrial metho 95% for use at home & it works great but down at the community shed we just use good ole Diggers metho straight off the woolies shelf. The diggers brand was half the price of the 95% i bought & it works exactly the same. :?:?:?
And yet the only time i have ever had blooming in my shellac finish was at home where i used the 95% - i put this down to the very high humidity in my shed at this time of the year.

[ubeaut]

Probably was the humidity.

It does make a difference as I said above if it's hald full of water you wouldn't even get the shellac to dissolve and unless it's marked Industrial Methylated Spirits it could be. If marked IMS it has to stick to the standards. 100% is the best 95% will be fine and unmarked could be dodgy. The unmarked is up to the manufacturer. If your not sure about the water content do the turpentine test and if it ain't clear then it's a pretty safe bet your shellac will bloom if it dissolves in the first place.

Oils ain't oils.

:U

[Rattrap]

Thanks for that. The Turpentine test is defiantly 1 i want to remember. Shellac is a favorite finish of mine. :2tsup:
When u say "add a little turpentine to the bottle and shake" u mean a small test sample of the metho or do u mean the whole metho bottle?
Is the metho effected by having a little bit of turps in it?
& do u mean mineral turpentine or gum turpentine?

Cheers.

[ubeaut]

Probably best to take a little out of the bottle and try it. Mineral turpentine does the job. Best to pour the meths into a clean bottle of some sort snf then add the turps and shake. you aly need a small amount of turps but under normas circumstances and with clean waterless meths you can add as much turps as you like and the mix will stay clear.

I test most of our 100% IMS this way because we have had wrongly marked drums in the past and that's a disaster for us because even the 5% of water in 95% IMS will stop waxes from properly combining when we make Shellawax costing thousands of dollars, it can also make a difference to the quality of our premixed shellac. Most manufacturers of premixed shellac use 95% IMS we only ever use 100%. Costa a little extra but I reckon it makes for a superior product.

It is not uncommon for 95% to have up to 10% water in it so buy quality product and not cheap unknown stuff. Although MSDS's may say 95% alcohol they often say >4% or >5% water meaning greater than 5%. Should say 5%. Oh yeah, and the denaturant should be around 0.03%.

If in doubt find the MSDS for the product you're going to buy and check out the water quantity and the denaturant. I have seen some with as much as 10% Methanol and that's not really the best of things to be playing with.

:U

[Rattrap]

Thanks so much for that info Neil, i'm going to make it a standard practice in future :2tsup:

[Horaldic]

Thanks fellas!

I've not got Neil's expertise but I can tell you it makes a substantial difference. I learned the hard way that the metho off the standard hardware shelf (diggers/walkabout etc) can have more than a third water in it. It also has other additives to make it less "palletable" (read more poisonous): commonly methanol, acetone and propanol.

One of the big pluses of using shellac-based finishes as opposed to resin-based or acrylic varnishes in my book is that I can avoid exposing myself to petrochemicals. So avoiding the nice little cocktail in shop metho is also important to me.

If (and this is a big if) you can get the shellac flakes (or buttons if that's your thing) to dissolve in metho you'll often end up with a patchy inconsistent finish.

I don't keep a big supply of the redistilled stuff either; because ethanol is hygroscopic. It absorbs water from the surrounding atmosphere and ends up less effective over time. Even with the lid screwed tight. I just buy enough for the jobs I have at hand.

[Paulphot]

Not sure if this will work woth metho (IMS or otherwise) as I don't know how the chemical would react with the seals but I have heard of people decanting things that are hydroscopic into empty (and cleaned) cask wine bladders, then expelling the air and only using the small amounts they need through the tap. It's meant to reduce the exposure of the product to air and it's moisture.

[mic-d]

For those interested in means of storing rectified spirit (~95% ethanol), keeping it dry or making it dryer you might be interested in this report (http://www.purdue.edu/newsroom/research/2011/110913LadischTapioca.html) from researchers at Purdue Uni who have found that tapioca pearls are very effective in drying ethanol, better than molecular sieves and easier to obtain. I don't see any problems with storing your IMS over it, tapioca starch is insoluble in alcohol. Worth further investigation as an application in French polishing, perhaps even storing shellac solution over the granules.

[Woodwould]

You can buy commercial desiccant for the same purpose, but I like the thriftiness of using tapioca.

[ubeaut]

perhaps even storing shellac solution over the granulesShellac should be well mixed by stirring or shaking before use. Can you imagine it. Frog spawn shellac. Hmmmm now that's something new and different with an interesting texture when it dries.

Shudder. 183317

[tea lady]

Maybe the tapioca could be in a little mesh bag of some sort? :shrug: If its not going to disolve its not going anywhere. :cool: I kinda like low tech solutions. I could make little musli tapioca pouches. :U

[mic-d]

Shellac should be well mixed by stirring or shaking before use.


Why's that? To redistribute the wax?

[tea lady]

Why's that? To redistribute the wax?I think he is refering to "shellac". But shellawax "glow" visibly separetes so we give that a good shake. :cool:

[mic-d]

I think he is refering to "shellac". But shellawax "glow" visibly separetes so we give that a good shake. :cool:

Shellac flakes have wax in them too ( unless it is dewaxed shellac) It may precipitate out some period after you dissolve the flakes. Remixing the wax is the only reason I can see for needing to shake fully dissolved shellac before use. BTW TL I like your idea of putting the tapioca in a little bag. I was thinking of running the quantity you need through a filter first, in case there was some loose particles. Your's is a much better idea.

[tea lady]

Shellac flakes have wax in them too ( unless it is dewaxed shellac) It may precipitate out some period after you dissolve the flakes. Remixing the wax is the only reason I can see for needing to shake fully dissolved shellac before use. BTW TL I like your idea of putting the tapioca in a little bag. I was thinking of running the quantity you need through a filter first, in case there was some loose particles. Your's is a much better idea.Sort of a tapioca tea bag I was thinking!:cool: Take it out before stirring? :U

[Woodwould]

Shellac flakes have wax in them too ( unless it is dewaxed shellac) It may precipitate out some period after you dissolve the flakes. Remixing the wax is the only reason I can see for needing to shake fully dissolved shellac before use. BTW TL I like your idea of putting the tapioca in a little bag. I was thinking of running the quantity you need through a filter first, in case there was some loose particles. Your's is a much better idea.
I mash up my flakes in a coffee grinder and then put them in the foot of a stocking or pair of tights before throwing them in a bucket of meths to dissolve (it saves filtering the stuff afterwards). Tieing up some tapioca in a stocking foot would solve the same issue.

[Claw Hama]

I don't have any trouble using any shellac flakes (current batch is Feast Watson), diggers metho (as long as its new or the lid has been kept tight), my current Aust Red Cedar desk job has had 3 coats of shellac (two with added stain) and three coats of wipe on poly over the top. Looks great, it will get another couple of coats of WOP before being installed on Tuesday.
I have never had any issues with wax etc. Many painters use it to seal old moulding and lining before painting to stop bleeding of old varnish etc.
After a day or so the wax collects on the botttom of the jar, you can decant it into a clean jar if you want. Always try and finish on a day with low humidity if you can and I try to make quite thin mixes so the metho evaporates before it can suck in moisture.

[rsser]

Haven't bought any recently but I've sourced Sceneys 95% in Mitre 10 hardware shops in the past.

[Claw Hama]

My 4ltr Diggers from Bunnies have 95% on them too.

[mic-d]

My 4ltr Diggers from Bunnies have 95% on them too.

Yeah, I've used both IMS and Diggers with identical good results.

[ubeaut]

Why's that? To redistribute the wax?

All shellac will layer when left to sit for any length of time. It's quite obvious with golden shellac or white shellac, yet virtually impossible to detect in blond, dewaxed, or our hard shellac, but it definitely happens and if it isn't mixed prior to use you run the chance of a finish that could craze or wrinkle or do other weird things in the fullness of time. You also take all the good stuff out and are left with the not so good stuff if you don't mix it.

This is why all our premixed white shellac has this in bold red on the label:

SHAKE BOTTLE WELL BEFORE DECANTING & STIR BEFORE USE


And our 5 litre and 25 litre bottles say:

IMPORTANT INFORMATION
This product will layer.
SHAKE CONTAINER WELL
before decanting, also shake or stir each
time the product is used.


People may think they are getting good results using their shellac straight out of the bottle, jar or whatever, without stirring but in the long run the results will be way better if you stir or shake. Honest.



:U

[ubeaut]

I believe Diggers have deleted the 100% IMS from their range. Could be wrong but that's what I've been told.

There's not a lot of call for 100% so it's pretty easy understand the reason for it being dropped.

Might have to start bottling it myself..... Nup not worth it.

:U

[tea lady]

Thanks for that info neil. :cool: I got 100% metho from the good paint shop in Upwey near me. :cool: Never tried with the "normal" stuff! :shrug:

[mic-d]

Thanks Neil. The Diggers I am using is the 95% rectified spirit. I haven't seen Diggers 100% where I shop...