Help! I have not encountered this before. The picture shows a walnut bowl I turned from a butcher block counter piece. The turning went fine. I have recently been trying Yorkshire Grit. I used it on the bowl as the final sanding medium. I then applied rattle can lacquer satin. Most of the piece turned out fine. However, I was left with spots similar to what you see in the bottom. The first spots were different shape than what is shown here. I have tried all sorts of things to no avail. I sanded the bottom back, cleaned it with acetone and then applied lacquer again. I have applied a number of coats of lacquer, sanding smooth after each one, thinking it was absorbing into the wood. Thinking that if I built it up enough it would blend in with the rest.
When I wet sand these spots seem to soak up the water different than the surrounding area. That led me to try to apply shellac thinking I would seal it. Still no change.
As you can see, the sides are just fine.
Does anybody have a suggestion as to what is going on here?
Thank you.

A couple minor questions.  First, is the "rattle can lacquer" nitrocellulose lacquer and lacquer thinner, or one of the newer products that contains other ingredients?  Second, was the shellac dewaxed?

If I do decide to sand back the lacquer finish I would expect that I would then try to apply poly. Although you shouldn’t apply poly over lacquer will there be enough residue of the lacquer in the wood to cause me problems if I do a good job of sanding?
I plan to teat the poly on the spot before I try this. I will sand it back there and apply some poly to see what happens.

Are you using the commercial product named Danish Oil or are you mixing your own?  If the latter, what is in the mix?

Something that just came to mind, is the cloudy area in your photo well adhered to the surface, or can it easily be peeled off?

While it might not be enough to fill pores and create a level surface, even two coats of a good danish oil should seal the surface.  My guess is that something is preventing the first coat from penetrating and bonding with the surface.  Any additional coats would build the film thickness, but not affect the lack of adhesion between the wood and the first coat.

My suggestion would be to take the bowl to a woodworking supply store, hoping someone there is a finishing "expert."

Mike

Curious about your issues with that platter.  Allowing drying time between coats, I've not had to apply more than three before the thirsty areas stop absorbing the next coat almost immediately.  But it sometimes takes several more coats, again with drying time after each, to build to a uniform sheen.

No doubt Ed will chip in that because danish oil includes a resin it is a film building rather than penetrating finish.  As soon as the pores are plugged, following applications stay on the surface of the prior coat.  At least that is my understanding.

You could try wet sanding with 400 grit sand paper and the danish oil.

Don Stephan wrote on Mar 1^st, 2021 at 7:24pm:


My experience and practice is consistent with yours, with the exception of this one platter.  I cannot explain it.