Oh dear, there's one i didn't think of...
We were all set for a totally water based system right from primer>top coat.
Now we're going to certainly go oil based i'm wondering if this presents a problem. I have no issue buying in new primer for the job. Thing is the door frames are terribly knotted. I did buy that Zinsser Bullseye i think it is, or Zinsser 123, whatever it's called that is for knots. It's shellac or something to that effect. Hopefully you know what i'm on about. If not then i can post back tomorrow night once i've been to the house & checked what the tin is.
Anyway, IIRC this is water based. Is this going to be ok to put on the wood & then oil based primer/undercoat/top coat on top? Obviously i'll be sanding it down once it's on. 180 grit i think is the finest i have. 80, 120 & 180.
Just wondered if it'd still be ok to use underneath oil based. Hope so.
Do not try to use Zinsser BIN as an undercoat
It dries too quickly. You will not be able to get a decent finish. Believe me, I discovered the hard way.
As an experiment I painted a 5 metre, 2 metre tall MDF bookcase years ago using BIN. Normally I would have used WB primer but I want to try something that was non grain raising. It was slower to apply (I used rollers and brushes), cost loads more and I had to wear a respirator.
Sanding time using WB would have been 2 days, the BIN took 3.5 days to sand flat. I even resorted to using Vodka to thin the paint which helped a little (denatured alcohol would have been better, but I didn't have any).
BIN is a great product but it is not easy to work with.
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