"jeffreydesign" wrote in message
oups.com...
With over 30 years of applying coatings I think I ought to know a thing
or two and honestly it all depends on the situation.

No one can definitively say you can't do this or that with Latex, Oil
(Alkyd) or Acrylics these days. In the "old days" you could NEVER put
any oil-based product over any latex or arylic product as the solvents
in the oil would strip the latex. Not true anymore, but latex or
acrylics have always been ok over oil-based product provided proper
prep work is done - the latex/acrylic must be able to adhere and since
latex/acrylic and oil-based coatings expand/contract differently - the
oil based undercoat must be cleaned and mechanically scuffed in a
consistent manner so the latex/acrylic gets a good mechanical bite into
the undercoat.

It has *not* always been okay to put acrylic latex products over oil
finishes. It has been the counsel of paint stores and manufacturers that
latex shouldn't be applied over oil. I've had several jobs over the years
that involved dealing with latex paint that had peeled because it was
applied over oil.

There are exceptions. Latex products can be used over oil base primer. In
some cases, exterior latex paint can be applied over old oil finishes.




Now for putting oils over latex/acrylic, I know that many paint mfg's
say it's ok (under certain circumstances) but it still makes me uneasy.

[...]

I agree. I'd rather use the same product (oil or latex). If I have to
switch, I'll prime with an oil base primer first.