Hi Ron,
Good question on the bags. I had dismissed them in earlier thinking on the count of possible solvent damage to the plastic. As well, I have been kinda stuck on the welded steel box because I wanted to put some heavy atmospheric traction to the interior of the stock vessels.
However, since this really the first time I've put this to paper, more questions than answers are bubbling up from my mental finish 'ferment pool. F'r instance: it is very difficult to get finish to permeate across the cell structure. How do I know?
Because I tried. There was a client who had a custom floor made of lumber cut from first growth walnut barn timbers. There were problems of finish, and actual tensile hardness. First I prepared as nearly perfect flat sawn and cabinet scraper'd samples as I could make. Next, I tried a couple of application methods, including extended puddling. Several dyed solvents were tested,using timed application techniques, Then, the wood was cross-sectioned and examined under the microscope against a grid.
My results indicated that even 100% dyed alcohol and acetone, were limited to a penetration of a three, to at the very extreme, a dozen cells. However, going from the end grain, as most of know, is like unto soda straws sucking up a soft drink. When I started thinking about stock wood, I really thought a 'magnum blaster' vacuum box would be needed to get X atmospheres.
However, your question caused me to consider two things: at what point in the stockmaking is it necessary to 'fossilize' the cells AND how deeply into the wood does this process REALLY have to extend? So: consider that the stock is very nearly finished, except for the very final line refinements and sanding. The inletting is complete.
Now, there is abundant open cell walls, tubes, vessels including end grain into which the finish may readily be wicked by vacuum. With a vac bag, there also would not have to be a total immersion pool. Also, whatever finish is being used, will be thinned to a predetermined state, and so will likely 'run' deeper than straight varnish.
Now I must go, but questions of 'how deep?' needs to be addressed. Also, will a 'shell' of finish [say 1/4 to a 1/2" deep]cause differential expansion and contraction stress against the 'core'? And, if this is such a good idea, why is it not more explored and part of the lore and literature? Is it it necessary or even desirable, given that a great many folks are pairfecktly satisfied with the finish they presently apply?
Adios.
