What the hell is leaching out of my door? (Photo)

[TattiePants]

My internal doors are almost 100 years old and when we moved in were covered in layers of varnish and paint. About 12 years ago we had all the downstairs doors dipped, allowed them to dry out then had them filled, undercoated and painted. The paint on one side of one door has never really taken, it’s as if the paint absorbs into the door and I’m left with brown streaks.

It’s the next room on my list to decorate and I’ve just noticed this brown liquid running down the door. Nothing’s been spilt on it so it has to come from inside the wood. What is it and how do I stop it leaching out in the future?

Offhand, the resin in knots, or planed knots bleeding through? Pattern is similar to images here? and in this search. Or, could there be iron lost head nails or pins underneath patched filler leaching through?

Ectoplasm?

It’s the resin in the wood , were they primed with a stain blocking primer ? If not you’ll need to sand back and do this I’m afraid . Zinsser primer is great for this

They were primed by the decorator but it was so long ago I can't remember what he used. The whole room needs redecorating (and I have some Zinsser) but it's really weird that out of 8 downstairs doors, it's only happened to one and only on one side.

DH thinks it's possessed and it's blood in time for Halloween (he's no bloody help).

No idea but ours upstairs are the same. Can't hang dressing gowns on the back of one without it getting covered. The others seem better 🤷🏼‍♀️ Just a sympathy message really 😅

Looks like that edge was never sealed. Sand it & Zinnser it

Mine are stripped unfinished 100yr old reclaimed doors and run with the same sticky brown liquid. It's especially bad when the house is a bit damp (our heating is not on yet).
Weirdly I have other reclaimed antique doors which don't do it.
I find it amazing that this sap has sat in the wood for so many decades - but it is annoying if you brush against it, I agree.

Pitch pine resin I think

It doesn't look like sap to me, it looks like dirty water that has leaked from above.

Will it clean off with WUL?

Or white spirit?

If it is resin, you can remove it from the wood by using a hot air gun to melt and boil it out, and scraping it away. After it has cooled, sand off the remainjng hardened varnish-like resin. I find that Aluminium Wood Primer (which is grey, not silver) is very good for sealing knots and resinous wood.

@AlicesAttic I think you might be right re heat as I’ve just spotted the same thing on another door. We’re trying to keep our heating off at the minute and although the house isn’t damp, it’s definite on the cool side. I think it must be the change in temperature.

+1 for Ectoplasm