Residue when stripping paint from pine door

We are trying to restore some old pine doors in our house. We used a heat gun to scrape most of the old gloss paint off which worked fine. But now we're left with a grey-green residue which in parts appears to have soaked into the grain. We have sanded the door with various grades of sandpaper and also tried a chemical paint stripper - but to no avail!
Does anyone have any ideas about what we could do next?
I did try some white spirit on one corner with some wire wool, but that didn't seem too good. Then I tried a little methylated spirits, this seemed to work better, and might be the answer we're looking for, but I'm concerned about the damage it might do to the wood.
Any help would be gratefully received!
TIA
Darren
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How old are the doors? Might be milk paint.
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Yep... sounds like milk paint. Do a search for "milk paint remover"
here's one..... http://www.antiquesupply.com/prod-milkpaint2.html
Bob S.
> Darren

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