Stripped pine doors - hygroscopic?

RogerS · 23 Sep 2006

Something that has been bugging me for a very long time is that some old pine doors that we had stripped many, many years ago seem to suck up moisture from the air on some of the rails. So noticeable in some areas that my wife thought we had water dripping from the ceiling.

I'm guessing that something went wrong during the stripping process (stripping agent inadequately removed/washed off?). Is there anything I can do to remedy this?

Scrit · 23 Sep 2006

Perhaps it's the lye (caustic soda) still at work. In the past I've been advised to scrape-out any white deposits from corners of panels, etc with a toothpick and then to wash off the surfaces with a dilute water/distilled vinegar (acetic acid) mixture to neutralise the lye which is alkaline. I still reckon that you need to seal the timber somehow, even if its just a quick wash-over with white polish or clear MDF sealant. If nothing else it will stop finger marks, dirt, etc penetrating (depends if you have kids in the house......).

Scrit

norman · 23 Sep 2006

Hi
I would go with scrit on this one. need to have the stripping agent stablised before anything else is used. you see this a lot after a hot tank strip, that has not been well washed off.

Norman

RogerS · 24 Sep 2006

So do I have to immerse the whole door in a bath of acidic solution or could I get away with surface application? Would lemon juice do, I wonder, as my missus hates the smell of vinegar

Scrit · 24 Sep 2006

I don't think it really matters whether or not it is citric acid (lemon juice) or acetic acid (vinegar), all you're after doing is to neutralise the alkalinity of the lye. When I've done doors this way it's just been a case of wiping the door over with a soggy sponge or cloth (soaked in the mildly acid solution), leaving 5 o 10 minutes then wiping off and allowing to dry. Following day I've simply gone over with a damp cloth again and that's been that, although this will raise the grain a bit :roll:

Scrit