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Methylated Spirits is termed denatured alcohol in the US. It is sold in the UK with a purple dye. It's primary contents are alcohol and methanol - the latter being less than 10%.
For a number of years I've avoided using the stuff, largely because of health reasons and the possible damage it may do to the optic nerve. At least that was the impression that I was under.
Then I come across this:

http://www.southend.nhs.uk/pathologyhan ... pirits.htm

Which seems to indicate that you would have to be drinking the stuff in decent quantities before it starts to damage the optic nerve. Presumably absorption through the skin (as in French Polishing), the risk is practically non existent.
Thoughts? or any toxicology experts? I'm afraid Everclear is not available in UK/Europe.

I think there was a fairly recent article in GAL comparing the relative dangers of solvents for FP.

The GAL article really didn't "weigh in" on the dangers, it was more of a study of how to compare labels and how to figure out which brands had what percent of what ingredients.
Seems the author found a wide variation in added methanol among brands.

Or, at least that is how I read it.

Your UK methylated spirits with 5% added methanol would be very low by US standards.
How does the dye work out if using for FP?

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I wonder if this is the same ethyl alcohol used in race cars?

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In the bottle the dye appears to be quite a strong purple colour. Some people claim it gives a caste on very light coloured woods when F.Polishing. I along with many others haven't noticed it. Occasionally I come across bottles that are water clear. Either they forgot to put in the dye or the dye isn't very permanent.
It has a multitude of uses:
http://en.wikipedia.org/wiki/Denatured_alcohol

There is a picture of the dyed stuff in the wiki article. That would be considered very light in colour, usually the dye is much stronger than that.
It seems very good at dissolving/working with Shellac.

This may answer your query - as I enquired about Meths and DA

Dear John
Thank you for your recent website enquiry detailed below
The Methylated Spirits you would buy from B & Q is a petroleum based product, whereas our product is Denatured Alcohol which is Ethanol based and I am pretty sure is the DA that you mention, but please do some more research as I am in no way an expert in this area
The only issue with purchasing Denatured Alcohol is that you need to register with HMRC to register to purchase, as it is liable to duty
This basically involves contacting them on 0845 010 9000, explaining that you want to buy DA and how much you would need on an annual basis and they will supply you with a certificate
So that we can supply you, we would need to see a copy of this certificate before we would despatch the goods
I hope this is of some help, if there is anything I can do for you, please do not hesitate to get in touch
http://www.reagent.co.uk/industrial-methylated-spirits
Charlie Screawn
Technical Sales

In Australia we get Methylated Spirits in both clear and with dye added but either way the composition is Ethanol 95% Water 5% so here it is not petroleum based. You should be able to download the MSDS sheet from the company supplying it in England to be sure of what is in it and in what pecentage . Cheers Bob.

I bought 99.5% Ethanol in Taiwan, no questions asked. It was a bit more expensive than the 95% stuff (actually, more like almost 3 times as expensive) but they didn't really ask any question.

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Not so sure I agree. If you look at all the Safety (MSDS) sheets from the UK manufacturers of Methylated Spirits it lists Ethanol and Methanol as being the main ingredients - both constituting 90% +. The vast majority of that content being Ethanol. Methanol is added as the denaturant in the 5 to 10% range. Factor in some water and the dyestuff.
Seems to me that it's Ethanol based.
If it was Petroleum based, would it solve Shellac? You can buy clear Ethanol as Fiddes or Morells 'finishing spirit'. It's pure Ethanol with a very small amount of Shellac added. Presumably that allows them to omit the Purple dye. Shellac flakes take quite a bit longer to dissolve in the finishing spirit than they do in Methylated Spirits.

Thanks for the info, I think therefore that B&Q meths is probbaly Ok for shellac in that case and DA is not worth the hassle

Michael, I do use pure DA for my French polishing, but then I do have access to the laboratories of a major university. Even there though we have to sign out the amount we take as it is subject to an HMRC license, it's amazing how we have to fiddle the books sometimes to balance them!

That said one of the university's maintenance men who has been doing nothing but French polishing the panelling, doors and desks etc for the past 30 years, gets the ordinary meths with the dye in and won't use anything else. Thinks I'm a bit weird taking the trouble to use pure laboratory grade DA. So don't worry about it, just get the stuff from B&Q or Axminster and get polishing.

Colin

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I'd been using, "Crown" and "Sunshine" brand of DA, which MSDS shows to be up to 75% Methanol.

My online research found that the US Sherwin Williams paint stores carry "Startex" brand of DA which list 75% Ethanol and 25% Methanol which is about as low as it goes in the US.
My local store carried it with no price difference from generic DA.

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