Caledonia Yawl project: Carbon, Graphite and laminations

This evening was productive. 

I managed to add the Uni-directional carbon fibre to the port side of the centreboard.

  

I also laminated another knee.

  
And also covered the port side of the rudder with epoxy mixed with graphite powder (west system 423) and a little colloidal silica (west system 406). This was a big step because now I can’t see the wood grain or the Kevlar weave pattern. All that remains is the shape of the blade, which is looking good.

  

Caledonia yawl project: laminating the knees and carbon on centreboard

Today I helped my friend get a new fridge in a house where the widest door was 28″ wide. We had to take apart the sliding door.

 

everything is back together but you can see the areas where i dug out the nails
 
This evening I managed to get a couple hours and I put the unidirectional carbon fibre on one side of the centreboard. I wet the surface with epoxy and the layed it down and squeegeed more epoxy onto the surface.

  
It’s not perfectly smooth, but I’m happy with the result. I’ll be covering it with graphite epoxy soon and that will be sanded smooth.

I also started laminating the knees that will connect the thwart to the gunnels.

  

I used 2 1/4 thick fir lamimations left over from making the stems. With some luck ill be able to cut them down the centreline and get two knees out of each one.

Caledonia yawl project: rudder tip and centreboard coating

This evening I was able to escape to the boat shed for a couple hours. If only I could manage on a couple hours less sleep a night I would make quick progress.

I added the last bit of Kevlar to the rudder tip

 

rudder tip gets covered with an additional layer of kevlar
 
I then started coating the centreboard with a layer of I in-thickened epoxy to seal the surface before I lay the unidirectional carbon fibre. The cedar is quite dry and sucks up most of the epoxy I painted on.

 

the wood grain really looks beautiful. (the lighter patch is where i had already coated a few weeks ago)
 
I also started to set things up to laminate the knees needed at stations 2 and 4.

the knees are a much tighter bend than the apron or stem

Caledonia Yawl Project: Rudder finishing

It is summer and quite warm in Vancouver and a now realize that I need to get my hands on some slower curing hardener. The West 205 hardener this weekend started to kick in just 15 minutes.  I’m going to go get my hands on some 206 hardener that will extend my working time in the heat.

I did manage to do one more small step in the rudder epoxy work.  I left the draped Kevlar long on the trailing edge purposefully. It was an idea I found in an article by Jim Derck called “Durable edges for centreboards and flip up rudders“.

Credit: Jim Derck in the Gougeon Brothers paper on Rudder Blades and Centerboards
Credit: Jim Derck in the Gougeon Brothers paper on Rudder Blades and Centerboards
Continue reading Caledonia Yawl Project: Rudder finishing