How can I put a clear solid (varnish type) finish on rough sawn lumber?
Without knowing at all the thickess of the wood; the species; the age; dryness; absorbency factor; eventually the buildup would bring the clear coat to the surface and beyond. In a very realistic sense the absorbtion you describe can only penetrate so far before it either leaches to the other side (Higly unlikely) or reaches the core of the lumber and backs up. Again, without knowing any details; we can only imagine in suggesting. Thank you for stating you’ve done TESTS. I advise it in every similar situation. You might however; expand the testing to a multitude of finishes, and stop using the one you’ve been using. There are OIL options; such as TUNG which are designed to absorb; fill voids and fibers; to eventually become the surface finish; after multiple coatings. A resin based product; IE: Epoxy; would allow less absorbtion. I’d be curious to know more details. Steven Wolf With all due respect varnish and Poly are two different substances/formulations. One of the things I strongly
