Inside surfaces

[tippie53]

I can't say that finishing the inside will do anything for the instrument . The only thing it will do is add cost . I go to many guitar shows and while there are a few builders that do it I don't think it helps sell the instrument . Player want tone and playability .
Sandem nice and blow out the dust

[dobe]

The guy I apprenticed with likes a light coat inside, claims it slows moistrure movement a bit.

[Jim_H]

I just watched John Bogdanovich's video series, and he coated most of the inside with one or more coats of what I think was Zinsser Seal Coat. He put 3 coats on the linings, head block and tail block. One coat on the inside of the soundboard.

He also put three coats on the mahogany back braces and center seam cover. I don't think I noticed him putting anything on the Indian Rosewood back and sides.

He didn't talk much about it other than to say that he 'Liked to', and mentioned something about slowing moisture transfer.

[tippie53]

this comes down to personal taste .