White haze on birch ply finished with Watco

[James Carmichael]

I built some shelves for LOML out of birch ply. After sanding to 220, she applied Watco Danish oil in a cherry tint. It really shows off the birch grain, but parts of the finish developed a sort of white haze or patina after drying.

I tried some spot sanding and applying more Watco, but whatever it is keeps showing. Any suggestions?

Thanks!

[Steve Clardy]

James. It may be the glue that is used on the plys. I have had oak and poplar ply do this. The plys are so thin, or in the case of red oak ply, the veneer is so porous that the glue used shows through. [Mainly imported plywood].
Either that or maybe you have sanded the ply too much in spots?
I normally do not sand veneer ply at all till I have the first coat of sealer on it.

Steve