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new to stripping...questions

Discussion in 'Strippers, Stitch-n-Glue, and Other Wood Composite' started by weflyfsh, Apr 24, 2007.

  1. weflyfsh

    weflyfsh Curious about Wooden Canoes

    I have started my first strip canoe. I am building a 16' laker. After building the strong back and installing the stanchions I finally started stripping. I am using eastern red cedar. Within the first few strips I started having a problem with the strip snapping and breaking as I put some force on them to make the bends. Some where were there were knots in the strip, but others were in perfectly clean strips. Also when I put the staples in to hold the joints together, the staples are breaking out the wood on the inside. I have temporarily stopped; so any suggestion would be appreciated.
    Thanx
     
  2. Todd Bradshaw

    Todd Bradshaw Sailmaker

    Assuming that you aren't putting more edge-set (sideways bend) or twist in the strips than strips can normally take, I suspect that the problem may be related to the orientation of the wood grain within strips and/or grain runout. Few strips have totally uniform grain orientation since wood isn't squirted out of a machine, but boards are cut from logs at various angles to the log's annular rings. When you then rip these boards into strips, you'll find that some grain orientations produce strips that will take substantially more bending force and twist than others. The ideal strip, once cut from the board, will have tight, parallel lines of grain visible on it's wide sides as shown in the top example of the attached drawing. The staple gun blowing chunks out of the back side is one of the telltale signs of strips with the grain running at a less than ideal direction.

    Not all boards, or all strips, have ideal grain for their total length and small knots can complicate matters (they can look kind of neat on the finished boat though if you can work with them). Grain also tends to run on and off the edges of strips more with certain woods than others.

    I think my best suggestion would be to "get to know your strips". Spend a bit of time checking out their grain, test bending them and trying to determine which ones have favorable grain orientation for tough bends or twisting applications. There are some spots on a stripper hull that have pretty severe bend, edge-set and/or twist and others that are just big, slow bends. Since this wood has shown a tendency to pop under pressure, cherry-pick your best benders for the tough spots and save the more fragile strips for low-stress areas.

    ...and double check your instruction book, just to make sure your strip-to-building-form orientation is correct as there are certainly some bends that no strip would be able to make.
     

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