Cutting Planks Around a Knot

When resawing lumber to make planking stock, you have a few goals in mind:

  • You want to create clear planks with no flaws or knots
  • You want to convert as much wood into planks
  • You want to minimize waste

When you buy a massive 2x12, there will be flaws scattered throughout the piece. This is the price you pay when the price you are paying is low. If you opt to splurg, you can easily purchase perfect clear grain wood for an astronomical fee. If you are budget conscious, you will find yourself picking up your Douglass Fir at Home Depot or Lowes, where a 16 foot board only costs $25!

This flatsawn board has a few checks and a few knots, but the majority of the board is clear with very tight rings. Ripping the board into three will yeild one flatsawn section and two quarter sawn sections with tight and close annual rings.

After the board was ripped and cut, it was time to resaw the smaller boards to create the 1/4 inch thick planking stock for the dinghy. It is easy to discard boards that have major flaws such as knots or checks, but this would be wasteful. Yes, a flaw will always be a flaw, but it can be worked around!

Remember, when planking the hull, there is always a section of the plank that overhangs and will be cut off. If the flaw is towards an end, placing it in the cutoff section will make the flaw disappear while making that plank usable!

What if the flaw is smack in the center of the board? Is that whole piece lost? Nonsense! We just need to work around that problem to extract as much usable wood as we can.

This gorgeous quarter sawn board had a big old knot right in the middle! To get as much clear stock out of this board as I could, I selectively resawed this board, carefully taking planks out of the board without involving the knot.

The top cut moves the knot over a bit, allowing the bandsaw blade to glide by in clear wood. This means that the first plank will be full height while no involving the only flaw in the board.

The process of cutting the top off to expose more clear wood on the side continues as you move across the board. The result is similar to the cut pattern when a log is quartersawn, where you form an alternating step pattern in the boards. The planks aligned vertically are all the planks that I was able to extract from this board without any sign of the flaw while the planks aligned horizontally are the scrap pieces that include the flaw.

Here, the board is reassembled, showing all the cut wood that came from it. You can see the off cuts that are flawed or not fair as they rest on top or on the side of the stack.

The good planking material extracted from this board will serve us very well as it is without flaws. If this board had been discarded, all of this material would have been lost! If the knotted section were to have been cut off, all the wood higher than the front plank would also have been lost. It is a bit more time consuming to orient the board in such a way as to extract as much clear wood as possible, but the cost savings are substantial and should not be overlooked.