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So how far from center is considered "free of center"?

Started by VictorH, November 05, 2011, 05:50:04 PM

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VictorH

In reading and learning from all of you, I have read more than once that a timber should either be cut with the heart centered or cut with no heart in it.  So my question is what qualifies a timber as free of heart.   My guess to this question is that the growth ring must enter and exit on different sides of the timber.  Am I right or wrong.

jueston

heartwood and sapwood are two different parts of the trees structure, the sapwood is used to move water up the tree, the heartwood holds sap and gives physical support to the tree.  in many types of trees the differance is obvious due to the dark color of the heartwood.
the reason for cutting box heart or no heart is that if you were to cut down the center of a log, and then make a cant which was half heart and half sap it would curl(towards the sap i think?)...

jueston

here are some random pics which show the color differance





paul case

On rr ties the outfit I sell to wants the heart at least 1'' inside. they don't like fohc cants for some reason. I think that fohc cants do tend to bow especially on smaller ones, like 4x4. Pc
life is too short to be too serious. (some idiot)
2013 LT40SHE25 and Riehl edger,  WM 94 LT40 hd E15. Cut my sawing ''teeth'' on an EZ Boardwalk
sawing oak.hickory,ERC,walnut and almost anything else that shows up.
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Brucer

All my FOHC Douglas Fir timbers are 1" or more away from the pith.

When I'm sawing a boxed heart timber I try to keep the pith in the middle 1/3 of the cant.

FOHC cants tend to move away from the pith at the ends. The longer the cant, the more the deflections. Some species move a lot more than others. Of the handful of species I've sawn a lot of, WRC and Birch have the most deflection, White Pine has the least, and Douglas-Fir has a moderate amount.

Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

Piston

Victor,
Do you mean free of heartwood, as in only sapwood?  Or do you mean FOHC as in no pith in the timber?  The way I understood your question was "at what point is the timber considered completely free of heart center" as in the pith, which may or may not be in the center of the tree.  (For example, the pith may be off center if the tree was growing on a hill, or in a strong prevailing wind, or growing at an angle.  In these examples, if it was extreme enough, you could theoretically mill the timber out of the geometrical center of the log, but not include the pith)

In the first picture that Jueston posted, the pith would be the dark circle in the middle, the heartwood would be the dark wood taking up a large portion of the log (depending on species), and the sapwood would be the light colored wood on the outer rings. 

Free of heart center refers to a timber milled so none of the pith is included in the timber.  It could have both heartwood and sapwood in it however.

The growth rings could still come out the same face of the timber, so long as the pith is not included.  The growth rings would have to be less than a half circle. 

Hope that makes sense.  ;) 
-Matt
"What the Lion is to the Cat the Mastiff is to the Dog, the noblest of the family; he stands alone, and all others sink before him. His courage does not exceed his temper and generosity, and in attachment he equals the kindest of his race."

Meadows Miller

Gday

Free Of Heart material in most country's is considered 2" away from the heart the way we do it in both Hardwood and Softwood mills is to saw down to a 4x4" center cant with the heart contained in it Mate  ;)

With Boxed Heat for beams and posts you want the heart in the center roughly and when you get into producing those you want reasonably strait logs too ;)

I will add that Heart is the Pith of the tree  ;)

Regards Chris
4TH Generation Timbergetter

VictorH

Thanks guys.  I was interchanging heart, center and pith as one and the same.  Appreciate the responses from everyone. 

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