Sometimes I receive wood that already has a finish on it. Like a recycled oak door that I demolished for the wood. So my question is, can wood having a finish on it already - be damaging to tools. Like if you plane a board that has glue build up on, it can sometimes chip your blades.
Will it dull the saw blades or chisels?
Should the wood be stripped first?
The finishes so far have been Poly or spar varnish, not built up like pre-finished hard wood flooring.
The other day I was ripping a 2x4 on my table saw and the cut started to run off, then I saw smoke and now I have a wobble dato blade.. haha Oh, did I mention that the board had about an inch bow and crown in it... It would have been cheaper to just buy a new 2x4, instead of a 2x4 and a new 10" saw blade!