Wednesday, March 4, 2009

Let the fairing begin!

With the stems shaped roughly, it's time to cut the sheer of the hull. The sheer is the line of the top of the canoe as it sits in the water that gives the canoe it's familiar shape. Cutting the sheer is pretty straightforward:Start by placing a batten along the sheer from the station molds and use that to draw a line to be cut to.

Once the sheer is completed, it's finally time to begin fairing the hull. For those not familiar with canoe or boatbuilding, fairing is simply taking the strips from a faceted state from the initial assembly of flat pieces and smoothing the angles to make smooth curves all around no matter where you go.

Note also that I have plugged the screw holes in the outer stems with dowels. This fills the holes first and foremost and it also adds a very subtle design element. The dowels will be visible when the canoe is finished and will be finely placed "dots" that show. I think they will look pretty neat. On my last boat, the only screws I used were on the gunnels at the deck ends. As a result of using the screws there, I had to plug the holes in this manner. Once it was done, I really liked the way it looked and decided that the next canoe would have these screw holes along the entire length for subtle decoration.

Another view of the stem.

The fairing process is fairly involved and takes a bit of time. Steps to be followed from initial fairing to ready for glass are as follows:

  1. Initial fairing- Either by hand plane, hand sanding, ROS with 80 grit paper. Whatever you feel comfortable with. The key here is to take the high spots where the planks meet and knock them down to make the hull initially fair.
  2. Filling- It's inevitable that there will be a need to fill somewhere on the hull. I did the filling after the initial fairing for a couple of reasons. First, by completing the initial fairing, I can better assess the spots that need filling. Second, I am going to sand the hull at least two more times and will be able to clean up anything that needs it on the next couple of sandings.
  3. Second sanding- Again with 80 grit. I know this sounds a bit aggressive, but the filler from step 2. is epoxy mixed with sanding dust (wood flour) and that stuff is hard to sand. I go aggressive to clean that up. However, care needs to be taken in order to not create dips and gouges with the power sander.
  4. Wet the hull- This is done to raise the grain of the wood fibers that may have been mushed down during the sanding processes. It also will highlight the spots where you still have glue that needs to be cleaned up. If you don't get all the glue/epoxy off the hull before 'glassing, those areas will show as light or blotchy. The way I see it, if something is avoidable, avoid it.
  5. Final sanding- This sanding is accomplished with 120 grit after the hull is completely dried out from the 4th step. This will prepare the hull for the 'glass and also knock off the raised fibers from the wet the hull step above. Once this step is complete, the hull is ready for 'glass and epoxy.
Hopefully, with the posts and pics, and now with the schedule I just laid out, things still make sense. I will be completing the sanding and fairing soon and getting to fiberglassing, so stay tuned.

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