Is this black mastic?

[KeiraEJ]

Hello,

I’ve recently removed a built in cabinet in my living room and found what seems like a black coat of paint underneath. I’m worried it might be black mastic containing asbestos. I’ve never seen it in person so I have no clue.

The cabinet had no bottom it was just the floor covered with some carpet. The carpet was not stuck to the black layer, it was nailed down in a few places and came off easily. The black stuff is not sticky at all.

I tried scraping off a little bit with a filling knife before I realised it might be dangerous and it came off quite easily. I read black mastic doesn’t come off easily so I’m quite confused.

If anyone has any ideas I would really appreciate your insight.

Thank you in advance!

 

[Tigercubrider]

It looks like old varnish to me. They loved dark stuff back then.

 

[KenGMac]

KeiraEJ, good evening.

Check out "Shellack" the Victorians loved this stuff on flooring, especially around the edges of rooms, between the carpet and the Skirting boards, on floors this material is a thick form of varnish that is a bitch to remove, there are several "modern" Chemicals that can get it of it available from the outlets that hire floor sanders.

As for the "Dreaded" Asbestos?? do not think so !!

 

[bobasd]

OP, its probably black paint.
the thing is are you intending to leave it or remove it?

 

[Deleted member 174758]

Check out "Shellack" the Victorians loved this stuff on flooring, especially around the edges of rooms, between the carpet and the Skirting boards, on floors this material is a thick form of varnish that is a bitch to remove, there are several "modern" Chemicals that can get it of it available from the outlets that hire floor sanders.

Shellac (note the spelling) wasn't normally used on floors because it water stains really easily (ever seen white rings on French-polished table tops), and in any case if it is there is no need to ever resort to using "modern chemicals" to remove it as it readily dissolves using just methylated spirits.

Floor varnish, on the other hand, often does require mechanical means to remove it and is far more commonly used on floors, although stained and waxed floors (or varnished floors which have been wax polished for many years) are not unknown as are dark painted floor boards as suggested above (again with years of waxing).

Any waxed floor will probably require mechanical removal (i.e. scraping with a floor scraper) as it resists chemicals well.

Be careful when removing old paint (pre-WWII) - wear a mask and wash hands after handling and before eating, and try to avoid sanding unless you have good quality dust extraction on your sander because it generally contains lead, a known cumulative toxin

 

[KeiraEJ]

KeiraEJ, good evening.

Check out "Shellack" the Victorians loved this stuff on flooring, especially around the edges of rooms, between the carpet and the Skirting boards, on floors this material is a thick form of varnish that is a bitch to remove, there are several "modern" Chemicals that can get it of it available from the outlets that hire floor sanders.

As for the "Dreaded" Asbestos?? do not think so !!

Thank you! That's a big relief, I was ready to buy an asbestos test kit.

 

[KeiraEJ]

OP, its probably black paint.
the thing is are you intending to leave it or remove it?

I was planning to remove it, just need to figure out the best way. I'm not too worried about it looking prefect though, I'll be putting some furniture in that spot anyway.

 

[KeiraEJ]

Shellac (note the spelling) wasn't normally used on floors because it water stains really easily (ever seen white rings on French-polished table tops), and in any case if it is there is no need to ever resort to using "modern chemicals" to remove it as it readily dissolves using just methylated spirits.

Floor varnish, on the other hand, often does require mechanical means to remove it and is far more commonly used on floors, although stained and waxed floors (or varnished floors which have been wax polished for many years) are not unknown as are dark painted floor boards as suggested above (again with years of waxing).

Any waxed floor will probably require mechanical removal (i.e. scraping with a floor scraper) as it resists chemicals well.

Be careful when removing old paint (pre-WWII) - wear a mask and wash hands after handling and before eating, and try to avoid sanding unless you have good quality dust extraction on your sander because it generally contains lead, a known cumulative toxin

Thank you! It comes off with acetone so I guess it's lead paint or varnish. Would it be safest to use a paint and varnish stripper?

 

[Deleted member 174758]

Modern chemical paint strippers such as the "public" version of Nitromors is nowhere near as effective as the older (highly toxic "trade") version which could lift almost anything other than chalk paint or milk paint. On the other hand it is a lot less toxic and won't kill anywhere near as many fish if you flush it down the drain and it ends up in a water course. Personally dont like them as their performance is very poor- they often require 3 to 4 applications to achieve what the old formulation did in one.

Incidentally a solution of household caustic soda will lift paint and varnish quite well, however the fumes are highly toxic and it dissolve the skin if you try to wash it off with water (alkali plus fat in the skin = soap) so it, too, needs to be handled with extreme care and proper PPE (including a chemical respirator, eye protection and heavy rubber glives) and good ventilation are a must

TBH rather than chemicals or sanding only I'd be inclined to get myself a carbide scraper with a replaceable blade, such as the Linbide (at under a tenner), and use that to scrape the majority of the surface coating away. That puts a lot less potentially lead-contaminated paint dust into the atmosphere. Finish off by sanding, but make sure that you connect something like a HEPA vacuum to your sander. You may find that the finish has sunk into the top of the wood sand stained that in which case a belt or floor sander might be needed to sand the toning out fully.

When sanding old paintwork always wear a mask, ideally wear a disposable "romper suit" (coveralls) and always wash your hands and face thoroughly (and take off your coveralls) before eating. Lead is to toxic and accumulates in the body if ingested. This is why heat guns (which can vaporiser lead into the air you breathe) have somewhat diminished in popularity in recent years