I have a question about using pressure pots, the kind they use to remove air bubbles from epoxy.

If you use a shellac (or a thin finish) with a piece of wood in a pressure pot, will it reduce or eliminate oxidation enough that the wood color will not darken?

Have to research that one!

Oxygen causes oxidation. I'd think a vacuum chamber would reduce that oxygen reaction. Not sure a pressure pot would do the trick. 

Pressure does not reduce the amount of oxygen in a pot only compresses it so since the volume of the pot does not change as it pressurizes there will be more oxygen. Now for a vacum it will be the opposite. Oxidation will resume when the piece is removed IMHO.

14 minutes ago, Gerald said:

Pressure does not reduce the amount of oxygen in a pot only compresses it so since the volume of the pot does not change as it pressurizes there will be more oxygen. Now for a vacum it will be the opposite. Oxidation will resume when the piece is removed IMHO.

I wonder, if the piece were put in the pot with wet finish and left pressurized long enough for the finish to cure, would it be protected from oxidation when it came out of the pot?

I am thinking along the lines of Gerald.  You may end up with a nice finish, but it will still be "just a finish".  Oxygen & UV will still pass through.

My reasoning is that if it were otherwise, we would finish all sides of every project and not worry about wood expansion & contraction...  If moisture, H2O, gets through the finish, a simple "O" by itself can.

...Without contact with air I don't think the finish would dry. Epoxy hardens through a chemical reaction.

1 hour ago, Larry Buskirk said:

...Without contact with air I don't think the finish would dry. Epoxy hardens through a chemical reaction.

You been using that stuff that DOESN'T cause cancer in CA?

51 minutes ago, Gene Howe said:

You been using that stuff that DOESN'T cause cancer in CA?

 

From what I understand EVERYTHING causes cancer in CA..