Kirf cut in boxed heart timber

I would not use any green material to build frame unless there are good reason to.

But the price of KD material and green materials are double the cost and sometime I have to find a way to build frame with lower budget.

Fortunately, we have good forest surrounding and we can source reasonably dry dead standing material. Limitation of these materials are sizes of logs that we will not able to get FOHC on bigger and longer materials.

So we applied kirf on timbers to focus all check in top to prevent it to check on side. Timber with boxed heart, it will tend to check where ever close face of timber to center so most likely, it will check on side.

We had one project that had time in between so we applied kirf right after we received this dead standing material, put bigger dannage under also side to air can go through to dry timber while waiting. We had about 10 days to leave this timber in our shop and this is the result.

  • M/C was average 18% when we received material and it came down to 16% at the time we start to plane.
  • Kirf need to be apply before plane so kirf on top can open.
  • We have seen the kirf opens average 1/4 inch so it is working.
  • We have planed 4 side after so timber is square with open kirf on top of beam, no side check.
  • We will be checking this timber next while to see if the system works.



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