Tuesday, January 20, 2009

Rudder blade all laminated

The plans call for an extra layer of fabric around the top of the rudder blade and down the leading edge.  I decided to apply this reinforcement before the final complete wrap.   

Then the wrap of carbon fabric went on in one piece.  I also had some light weight fiberglass cloth (It seemed too light to be 6oz, it is probably 3.7oz) and applied this as the final layer for abrasion resistance.  

It would have been a good thing to use peel ply on this final wrap.  Just using plastic results in excess resin sitting on top of the fabric here and there.  But the final result is not bad for a hand layup.

I'm fairly happy with the final shape.  The overall thickness might be a mm thicker than the plans template,  and the trailing edge might be ~3.5mm thick.

The blade weight is 4.78 lbs and with the laminations complete  I can now move onto the rudder sleeve.  In this part the blade will actually be used as a mold.

Monday, January 12, 2009

Sheathing the rudder blade

January 2009 is just moving on at lightspeed so I thought I should post some small progress made on the rudder blade.

The Christmas break gave me the opportunity to stand back a bit, review other builders work, and it did not take me long to see that I made a mistake in the rudder blade uni-directional re-inforcements.  You never apply uni-directional directly onto the foam substrate directly.  It is always applied on top of some bi-directional re-inforcement.  In any event I somehow went ahead and laid down the carbon uni directly on top of the foam and the wrapped high density core.  Not as per the plans direction.  The plans call for the uni-directional to be sandwiched between the two layers of sheathing.  This was a strange error for me considering that I laid up the daggerboard correctly last winter.

I considered routing out all that unidirectional, but decided to leave that half of the rudder blade as is and make the other side correctly.  If it breaks at some point - my bad.   It will be my rudder blade half made right.

Here is a picture of the the complete rudder blade wrapped and the 6 oz carbon fiber (2x2 tweed weave) wetted out with the uni-directional apllied correctly on top of the cloth (at least on the one side).  

I'm in the process of smoothing out and rebuilding the appropriate shape over the uni-directional fiber before I apply the final sheathing layer.  The shape and overall thickness seems OK at this point.