I make fireplace mantels from reclaimed red pine, doug fir, and yellow s. pine timbers (originally milled 1874-1920; average size 5-6" thick, 10-12" deep) The yellow s. pine is especially sappy/pitchy. On a recent mantel, the pitch spewed/spit out once the fireplace warmed up some.
In your opinion, can YSP be used appropriately for fireplace mantels? How would you suggest we deal with preventing so much sapping (via kiln drying)? Short of kilning, can a finish (oil poly or shellac?) reduce or prevent the sapping upon heat? Some folks tell me the age of our old timbers should have reduced the pitch some, but that is not our experience. Thoughts there too?
(Sawing and Drying Forum)
From Gene Wengert, forum technical advisor:
I suggest that you heat the wood to drive off the sap that would be liquid at room temperature and a bit hotter. I suggest 180 F for about 24 hours.