Tom Banes wrote:
Dan:

A lot of tack cloths are just a hunk of cheesecloth soaked in raw
linseed oil, which takes "forever" to dry (cure if you like). Getting
mineral spirits on the tack cloth diluted the RLO enough to transfer
some to the surface (hence the wet surface you mention).

I'd wipe the surface clean with more mineral spirits, let that dry
(minutes, 1/2 hour?), and I suspect no sticky will be left. If so,
proceed with whatever your planned next step is. You may want to air
out the tack cloth before you use it again - not too much, but a bit
(1/2 hour or so). Or buy a new one.


....
Problem solved! Sprayed on Formby's Build-up Remover, rubbed it with a
cloth; rubbed it off, and its now just like it should be.

I wish I knew what went wrong so I could avoid it in the future. Maybe
it was the tack cloth. Tom, are you saying it was the raw linseed oil
in the tack cloth?

Dan