Drying Rounds

Advice on dealing with the inevitable cracking in a round slice of a log as it dries. May 21, 2009

Question
Is there any good way to keep a large round from cracking as it's drying. Some sort of a tightening bander?

Forum Responses
(Sawing and Drying Forum)
From contributor J:
Binding it won't help. Read up on PEG (polyethylene glycol).



From contributor U:
Seal it with paraffin. I seal all my turning blanks and endcuts with a thick layer of paraffin wax. It isn’t guaranteed to stop checking, but it's the best you can do.


From Gene Wengert, forum technical advisor:
The round cracks because the outside circumference wants to shrink quite a bit, while the core prevents this. The circumference may try and change 8% while the core shrinkage is about 4%. You can dry it very slowly (such as parafin wax) and hope for the best. Or you can cut three of these disks and then put a saw kerf in a different spot in each one. After drying, cut out the major split, making a pie-shaped wedge in disks #1 and #3 and then carefully cut replacement disks from #2. Because the grain is the same in adjacent disks, this "repair" will be nearly impossible to see.


From the original questioner:
So should the saw kerf go from outside to middle? Meaning don't cut the pie out of it yet, just one saw cut from outside to middle?


From Gene Wengert, forum technical advisor:
Yes, as that crack will become the only major crack. We cut the pie wedge after drying so the sides are straight and the replacement piece will fit snugly and be easy to glue, etc.