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Dengue
17th January 2019, 01:50 PM
Our beloved Benign Dictator is forever warning us to use very low water level alcohol with shellac flakes and dewaxed solutions etc, not the metho stuff that you can find in hardware stores with up to 20% water.

I finally found some Ethanol with < 0.81% water from Sydney Solvents (https://www.sydneysolvents.com.au/ethanol-5-litre).

No connections with this company for me, just letting everyone know that low water alcohol can be purchased. My 5 litre bottle arrived today by Aust Post, free postage

justonething
17th January 2019, 03:19 PM
I just checked. It's free postage to my place. Thanks for the heads up

Skew ChiDAMN!!
18th January 2019, 10:14 AM
Now added to my shed post-it note, listing suppliers. :)

pach
18th January 2019, 11:19 AM
Now added to my shed post-it note, listing suppliers. :)

Good Idea! Pity there isn't a list of suppliers we can all share on this forum.... maybe we should start one ;-)

Chesand
18th January 2019, 01:11 PM
Any decent paint shop should stock 100% Methylated Spirits. It is available at Paint Spot stores here in Melb in 1 litre bottles and possibly larger containers.

woodPixel
18th January 2019, 02:48 PM
I use Sydney Solvents for IPA.

They are an excellent company. Thanks for the tip on IMS!

For 100% IMS you can also get it from The Paint Place on special order (1, 5, 20L). They sometimes have it on the shelf. Price will nowhere be as good as SS however....

Agreed we need some sort of shared Google Spreadsheet of products and suppliers!!!!

woodPixel
18th January 2019, 02:54 PM
Edit! I was going to mention they usually have highly refined versions of most of their chemicals for a few more $$.

Here is the 99.9% IMS: https://www.sydneysolvents.com.au/methanol-technical-grade-5-litre

Mobyturns
18th January 2019, 07:07 PM
Only one small issue - alcohol is hydroscopic. It will readily absorb moisture from the air, so once the bottle is opened the ongoing purity of the alcohol is highly dependent upon the moisture content in the air that replaces used product.

taz01
19th January 2019, 09:53 AM
Only one small issue - alcohol is hydroscopic. It will readily absorb moisture from the air, so once the bottle is opened the ongoing purity of the alcohol is highly dependent upon the moisture content in the air that replaces used product.Would something like bloxygen work to stop this, or is the cost not worth the effort?

Robson Valley
19th January 2019, 12:38 PM
What you do is to decant say 750ml into a "working bottle" and seal the original.
We needed anyhdrous ethanol at LaTrobe in the lab. Did it with molecular sieve,
cheaper than buying it. Beer bottles with crown seals. Kept very nicely.
The molecular sieve can be recycled in an oven.

Skew ChiDAMN!!
19th January 2019, 02:22 PM
For a long time I used to inflate a balloon in the air-space of various bottles, using a straw down one side to let air out as the balloon inflates, and then plug with a cork. But modern balloons are so cheaply made that the volatiles tend to perish them way to quickly. :sigh:


Would something like bloxygen work to stop this, or is the cost not worth the effort?

That'd work,we use it for our iced wines and botyris, but I don't think it's really practical for the "working" bottle.

IMO you're better off using one of the concertina style squirt bottles with which you can slowly "collapse" the bottle as contents are used and keep air out. Does need an air-tight cap of course... and to be made from a material that doesn't consider the contents a solvent. ;)

Now, the original bottle you decant from... that's a different story. I see no reason to not argon that... the price is affordable. The stuff we use is around $25 inc. shipping from the US and gives about 120x 750ml uses. That's... what...? 20cents for each 750ml "empty" when topping up a bottle?

I should mention that our stuff is not 100% argon. I believe it also contains Nitrogen and CO2... but the original Bloxygen recipe was pretty much the same mix.

It is sold as a wine preserver, not a paint preserver and may react with certain finishes. I haven't tried. :shrug:

Mobyturns
19th January 2019, 03:03 PM
I treat any product that can suffer from evaporation of thinners, or absorption of water by decanting into smaller containers pretty much on first opening if possible.

For say 4lt of lacquer I usually stir thoroughly then decant into 2 x 1lt cans plus 3 x 500ml cans then 2 x 250 ml cans as this best suits my usage needs. The size range means that product exposure to air can be limited. Something like DNA I use a storage and a working bottle to minimize exposure to air for the storage bottle. It is only ever opened to decant some product that will keep me going for a few jobs, then I immediately close the storage bottle tightly.

Dengue
19th January 2019, 03:10 PM
When decanting into 750ml empty wine bottles, does anyone use the vacuum wine stoppers to extract the air and keep the stuff fresh? I do it with oil, no problems, but worried I might be creating a bomb with the ethanol or lacquer thinners under vacuum

Just found on the Internet:


The boiling point of ethanol is 79*C and under vacuum (28 inHg) it drops to around 34*C. We typically use a rule of an additional op-temp of 50 degrees Celsius above the boiling point of the solvent is enough to boil the solvent and maintain that boil.

so, at 34 degC and higher, can I assume the ethanol liquid under vacuum becomes a gas. Does this mean that the bottle will be filled with high pressure gas, ready to explode?

I wish I had paid more attention in my Chemistry classes

woodPixel
19th January 2019, 05:32 PM
Couldn't you just use a bottle of welding gas? Argon or CO2? Helium in a pinch?

Robson Valley
19th January 2019, 06:24 PM
Welding gases? Sure you could. The concept is the issue of water/humidity/H2O in the ambient air.
To be anhydrous, nothing else matters, agreed? As long as you get a bottle of dry gas, you're done.

Look into ceramic "molecular sieve." You can regenerate it and it has been doing a dandy job
of dehydrating alcohols for decades. Even as far back as I go.

Swifty
24th January 2019, 05:10 PM
Edit! I was going to mention they usually have highly refined versions of most of their chemicals for a few more $$.

Here is the 99.9% IMS: https://www.sydneysolvents.com.au/methanol-technical-grade-5-litre

I don't think that link is IMS Woodpixel, the description says 100% Methanol, which is the nasty version of alcohol. IMS is mostly Ethanol with a dab of Methanol to make it undrinkable.
I am guessing that pure methanol should not be used as a solvent for shellac!

ubeaut
26th January 2019, 09:50 PM
Do not use Methanol it works but is highly toxic.

Methanol used to be used to denature ethanol by adding 10% to the alcohol to make it unpalatable and nauseating for recreational use. The addition of methanol is what gave us the term Methylated Spirits spirits, or Metho / Meths.

Methanol is mostly no longer used as an additive here in Australia. However in the USA it can make up as much as 50% or more of the mixture in Denatured Alcohol

Where to buy 100% IMS
You can buy 100% IMS (100% Ethanol) in Australia, quite readily if you are prepared to buy it in 4, 20 60 or 200 litre containers. 1 litres are much harder to come by but are available as per the original post.

Water absorption and shellac

There should be no real need to bother too much about the water absorption of 100% IMS. So long as the container is kept sealed when not in use it shouldn't absorb enough moisture from the air to hinder it's usefulness for shellac which will work fine with 95% IMS, which in turn could have up to 10% water in it even though it's only supposed to have 5%. Leaving the lid off a bottle for a whole day in really humid weather wouldn't make it unusable. Probably get away with leaving it off for a week, but that would just be dumb.

Shipping and postage.
I'm very surprised that it is being sent through the mail Australia Post as it is Highly Flammable Hazerdous Goods and as such is not allowed to be carried by Australia Post and for most freight Companies and Couriers there should be a Hazardous Goods surcharge of up to $20 per item above regular price.

Some transport companies like Star Track refuse to carry it. Or used to some 10 years ago after hellishly expensive cleanup due to a DG spill.

The above is why we don't sell it, even though we would have up to 1000 litres of it in the factory at any one time.
Hope this has been of some use.

Cheers - Neil
THE BELOW :aro-d: SHOULD NOT GO VIA AUSTRALIA POST :blowup:

https://www.sydneysolvents.com.au/assets/alt_1/SETHANOL5LTR.png

woodPixel
27th January 2019, 04:15 AM
My apologies for causing confusion. I need to write this down and try to memorise it.

Thanks to all for clarifying.

(100% IMS (Industrial Methylated Sprits) ISNT methanol/methylated-spirits at all, but ~100% ethanol + denaturant).