Setting the pitch

Other Versions
Spanish The why and how of setting the pitch in heart pine. October 15, 2001

Question
I recently bought recycled heart pine to make jewelry boxes. The first one turned out great, but now I'm concerned about setting the pitch. What does this mean?

Forum Responses
Setting the pitch in pine refers to heating the resin in the pine to a temperature that hardens or "sets" it so it will no longer flow as a liquid. It is best done in a kiln with a temperature of around 140 or 180 (I'm not real sure on that). If the lumber is only air dried, the pitch is set by the highest air temperature obtained during the process. The resins in the wood will not run if the temperature stays below that highest temperature, but if it gets hotter than that, the pitch will liquefy once again. I'm pretty sure that the size of lumber has an effect on whether all the pitch gets set to the same degree, because of penetration of the heat into large timbers and the drying method used. Check the archives under setting pitch for more info.

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We suggest no cooler than 160 F and 180 F is better.

Gene Wengert, forum technical advisor

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Is it necessary to set the pitch on recycled heart pine lumber that's 50-75 years old?

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Probably not necessary.

Gene Wengert, forum technical advisor

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What about "sinker pine" or longleaf?

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Setting the pitch would be advisable on sinker and longleaf--in fact on all pine (except the old stuff that has been used for 75 years already).

Gene Wengert, forum technical advisor