Paint Stripping - "New" Nitromors is hopeless.

[Skywave]

Caustic soda (NaOH) is a very powerful de-greaser. I use it often in the kitchen for removing baked-on grease from steel cookware items that have been used in the oven. I have also used it occasionally to de-grease steel panels prior to painting. Five precautions are essential though. One: always wear protective clothing - rubber gloves for hands and goggles for the eyes. Two: do not use it on aluminium. Three: use it in an area with plenty of ventilation and avoid breathing in the fumes. Four: always add caustic soda to water, never the other way round. Five: Caustic soda will attack any organic compound: that not only includes natural bristle brushes, but also human tissue! Therefore, test a small sample of the material to be treated first. Caustic soda is readily available from a well-known chain of D-I-Y stores.

I also use acetone as a general purpose grime remover. But as above, test a small sample of the material you intend to use it on first. Acetone will attack most plastics and many other synthetic compounds. Finger-nail paint remover is diluted acetone. I avoid that but buy the genuine article in 500 ml. bottles.

Al.

[G6Tanuki]

Originally Posted by Skywave

Caustic soda is readily available from a well-known chain of D-I-Y stores.

At a silly price. The best source of it I've found locally is farm-suppliers: my local one sells 5Kg drums of the stuff for around £10 +VAT. It's used for cleaning milking-machines (milk, being a mix of fats and proteins, tends to stick to pipework, tanks and pumps rather well: NaOH solution saponifies the fatty component and denatures the proteins).

Boatyards are the best/cheapest source of acetone: it's the standard solvent for styrene GRP resin. They also use it for flushing out the fuel-systems of outboard motors that have fallen overboard.

[vidjoman]

Dishwasher tablets contain Caustic Soda and are useful for soaking things to remove grime etc. just heed the advice above about aluminium etc.

[kalee20]

I bemoan the disappearance of 'proper' Nitromors, but the active ingredients are rather nasty. Methylene chloride is believed carcinogenic,and methanol (methyl alcohol) is much more toxic than ethyl alcohol (fermented sugar), and attacks the optic nerve if you haven't drunk enough to kill you (which isn't very much).

We just have to put up with it... and experiences of alternatives are most welcome!

[AC/HL]

If you have access to a cash-and-carry, beer line cleaning fluid is also largely Sodium Hydroxide.

I know some of you are immune to danger, but this is quite a dangerous substance, as are a lot of the other ones mentioned earlier. It's probable that manufacturers have reasons other than Legislation (if they need them) to be cautious about what they supply to Joe Public for unsupervised use.
No win no fee comes to mind, they can't get away with just blaming the user any longer, or relying on them being too embarrassed or stoical to come forward.

A lot (most) of us have experience and aptitude with such things, or even just a healthy respect for the unknown, but there are many Frank Spencers at large!

[Skywave]

Originally Posted by kalee20

. . . methanol (methyl alcohol) is much more toxic than ethyl alcohol (fermented sugar), and attacks the optic nerve if you haven't drunk enough to kill you (which isn't very much).

Methyl alcohol: isn't that essentially the same stuff as isopropanol alcohol (I.P.A.) or am I thinking of methylated spirits?

Al.

[G6Tanuki]

Having spent three days daubing a Sodium Hydroxide paste on to the top of the case it's at last starting to show some signs of the paint shifting.

[G6Tanuki]

Originally Posted by Skywave

Methyl alcohol: isn't that essentially the same stuff as isopropanol alcohol (I.P.A.) or am I thinking of methylated spirits?

Methanol - also called "wood alcohol" - CH3OH - is the fundamental alcohol in methylated spirit; however methylated-spirit is "Denatured" methanol in that it has other things added to it [dyes, nasty-tasting deterrents].

Isopropyl Alcohol - C3H8O or C3H7OH - is a 'secondary' alcohol. It's also often sold in 'denatured' form [with additives].

Don't try drinking IPA - it gets metabolised to Acetone - and will cause 'Ketosis'.

[McMurdo]

I think Strip-Away-Pro is the old formula? Made by Langlow.

STRIP AWAY PRO is a traditional methylene chloride based stripping compound

from the Langlow datasheet.



http://palacechemicals.co.uk/shop/strip-away-pro-copy/

[Nickthedentist]

And it's even available on eBay: http://www.ebay.co.uk/itm/The-best-5...-/111374211860

"For professional use only", they claim.

Good find, Kevin.

[Nymrod121]

Originally Posted by G6Tanuki

So - what do people use these days to shift old paint??

I found B&Q's 'in-house' product to be more efficient than the present-day Nitromors formulation, when used to strip old varnish from a Pye Black Box cabinet. I haven't used it on metal though.
Best wishes
Guy

[ronbryan]

I've been using an old tin of smooth Hammerite (circa 2005) to paint a drain pipe. I found that the Hammerite Brush Cleaner and Thinners product is no longer available from B&Q, Homebase and Halfords, no doubt due to solvent regulations as detailed in previous posts, even though it is still mentioned on current tins of Hammerite. I was recommended to use Cellulose Thinners as a substitute brush cleaner, but although more effective than White Spirit on the old formula Hammerite, it was still not good enough to clean my brush effectively.

Looking around for household solvents, in the absence of a reasonable quantity of Acetone, I found that unleaded mower petrol worked well as a brush cleaner, followed by wiping, then soapy water to get rid of the remaining solvent.

Ron

[paulsherwin]

Originally Posted by G6Tanuki

Methanol - also called "wood alcohol" - CH3OH - is the fundamental alcohol in methylated spirit; however methylated-spirit is "Denatured" methanol in that it has other things added to it [dyes, nasty-tasting deterrents].

Consumer grade 'methylated spirits' is generally made with ethanol nowadays. I've seen two reasons quoted for the change: firstly, ethanol is cheaper than methanol, and secondly, some people will try to drink it no matter what disgusting additives you put in, and from a harm reduction perspective it's better that they drink ethanol. This hasn't been widely publicised, as the old poisonous image probably does deter some abusers.

[lesmw0sec]

Originally Posted by ronbryan

I've been using an old tin of smooth Hammerite (circa 2005) to paint a drain pipe. I found that the Hammerite Brush Cleaner and Thinners product is no longer available from B&Q, Homebase and Halfords, no doubt due to solvent regulations as detailed in previous posts, even though it is still mentioned on current tins of Hammerite. I was recommended to use Cellulose Thinners as a substitute brush cleaner, but although more effective than White Spirit on the old formula Hammerite, it was still not good enough to clean my brush effectively.

The main component of Hammerite thinner/cleaner is Xylene, if you can get that elsewhere.

Les.

[Boom]

I used some of this new fangled paint stripper on a gramophone horn and although it took longer it did the job fine without gassing everyone in the house so I am personally in favour of the newer stuff.

As part of my home brewing hobby I occasionally distill a drop or two. I find that brewing yeasts do not give out any Methanol (64degrees) these days only Ethanol (78 degrees). I suspect that this is deliberately done by the yeast suppliers.

[kalee20]

Originally Posted by paulsherwin

Consumer grade 'methylated spirits' is generally made with ethanol nowadays. I've seen two reasons quoted for the change: firstly, ethanol is cheaper than methanol, and secondly, some people will try to drink it no matter what disgusting additives you put in, and from a harm reduction perspective it's better that they drink ethanol. This hasn't been widely publicised, as the old poisonous image probably does deter some abusers.

Not quite.

First the chemistry: Methyl alcohol (methanol) is the simplest alcohol. It is fairly volatile,and highly poisonous. But it is a useful chemical and a good solvent.

Ethyl alcohol (ethanol) is a bigger molecule, the next simplest. It's the 'alcohol' in drinks. Far less poisonous, and less volatile, although still evaporates readily.

Propyl alcohol (propanol) is bigger again,and exists in two forms (hence the iso bit). More poisonous than ethyl alcohol, though it poisons in a different way from the methyl stuff. Less volatile than either of the other two, so very useful as a cleaning solvent.

And there's butyl, pentyl, hexyl etc but they are far less important.

Traditional methylated spirits always was mostly ethyl alcohol, but did have some methyl alcohol in it (about 5%), which is why it is so-called. The way it was produced, gave a bit of methyl alcohol as a by-product, and as its intended use is as a fuel and general purpose solvent, there was no need to incur extra cost by purifying it. Dyes and bad tastes are added. Of course, if a process could be developed to produce purer ethanol directly, that would be preferable from all points of view, which brings us to Paul's post.

Methanol in the old-fashioned Nitromors was present because it's a good de-greasing solvent but it is also miscible with water - so it won't just run off damp wood in the way trichloroethylene would.

Do the 'new' paint strippers strip 'new' paint properly? If so all is well for the paint industry.

[Bazz4CQJ]

It's kind of curious that on 19th July I gave a nod to Wickes' product and someone else gave a nod to Wilkos' product, but seems like those inputs have been overlooked. Paint stripping has come up before on the forum and I recall that one member was impressed by "Ecostrip" (I think) which is available from Homebase. Curiously, that too seems to have been overlooked. Yesterday someone gave a nod to B&Q's product; time will tell.

[chipp1968]

I have used stripper on a couple of projects , both to remove paint from a surface that was one polished wood. One being a green painted oak panel (Actually from the ocean liner Olympic )
The stuff was very slow working, quite annoying and needed constant re application while using wire wool. Eventually I got it all off .
One thing going for it though is that that it left all the original grain filling etc .A couple of applications of sanding sealer then a beeswax applied with fine wire wool and it came up like it had been french polished !

[McMurdo]

I agree with chipp about the new stuff.
I used B&Q's 'Diall' brand which is a thick white gel and solvent based, stripping a 30's laquered coating. Had to spread it very thickly indeed, it took a good 15mins to soften anything, had to be scraped exactly on time, re-applied, scraped again, reapplied, wire-wooled etc. The coating turns to a treacle-like goop that will ruin & cake your wire wool in one pass. It sticks like glue to the scraper blade and anything else it touches. I used almost an entire bottle on the one radio. It doesn't cause the laquer/paint to bubble, just softens it. It's up to you to do the physical stuff. if you leave it a few minutes over the time on the surface, the solvent bit evaporates leaving a nasty brown sticky treacle all over the wood and you need a new dose to soften that as well.
On the plus side, the goop filled the worm holes and grain then solidified.