Tuesday, September 20, 2011

More small jobs

 I've been working toward glueing down the last remaining portions of the deck.  The only parts that weren't permanently attached were  the deck panels above cockpit sides.

   I've been thinking for some time about adding positive floatation to the boat.  I really don't like the idea of only relying on sealed bulk-heads or air bags.  A collision can easily breach a sealed area of the boat or even multiple areas.  So I decided to try adding expanded polyurethane foam as floatation material.  Since the very aft section of the boat behind frame 169 is not accessible, the time to do this was now.  In order to create a temporary mold for the foam, I duck taped plastic to the underside of the cockpit floor and constructed sides to hold up the foam so that there would be a space between the outer hull and the foam.  I poured in the non expanded mixture and watched the foam grow.  Unfortunately the foam leaked into areas where I did not intend it to be.  What a mess!  I spent quite a bit of time cleaning up this wayward foam, resulting in bloody knuckles and scraped arms.  The picture above shows the foam after I cleaned it up.  To the left is the stern.  The foam is stuck to the underside of the cockpit side panel.  I cut a way the foam in the last nine inches of this panel since I eventually need to cut an access hole here in order to get to the spin sheet turning blocks.  

 The foam does provide significant stiffness to the cedar strip portion of the cockpit (shown in an earlier post).  Since I decided not to continue using the expanded foam anywhere else in the boat.  I added some stiffeners to the sides of the forward cockpit shown to the left.  For the rest of the boat, I'm just going to add pink insulation foam underneath the deck panels.  I'll augment this fixed floatation with some air bags as well.  

 Deck is completely sealed -  After the battle of the foam, and adding the stiffeners, I went ahead and glued down the aft deck panels.  I then cleaned up excess glue and took a router to the gunwale joints using a 3/8th in. radius router bit. 
  I hadn't used a router for something this big in quite a while so I forgot a few basics, like; make sure that the screw holding the bearing on the router bit is tight.  The picture to the right shows some filler that I had to add because of this oversight.  Once the filler dries, I'll clean it up and re-route that section of the gunwale.

The last little bit of work that I accomplished was to fabricate a piece of mahogany for the very front of the cabin.  The picture below shows the result.  

Tuesday, September 6, 2011

Cockpit side curves

We've had a small debate about the curves between the aft deck and the cockpit sides.  As described earlier, I made these out of 3/8" x 3/8" cedar strips formed around curves in the frames and a couple of curved support blocks.  These strips were glued together and held in place with staples while the epoxy set.  I really only used cedar because it was easy to work with and is rot resistant.  I had intended to glass and paint over this whole area.  

To make a long story short, my kids think that I should not paint over the curved sections and instead should just varnish this area.  They think that it would be a nice continuation of the (natural cedar) cabin top.  I agree with them, but to go with this look I have to remove a whole lot of staples (probably a couple hundred), most of which are under a layer of epoxy.    I've decided to give in on this - it will probably take several hours to get them all out, but it will probably be worth it.  Of course I need to do this soon because I'm not too far away from glassing the entire deck.

A bunch of small jobs

 Work on the boat over the Labor Day weekend consisted of a bunch of small jobs that really don't look like much to friends and family.  The most visible mini-project was reinforcing  the bow prod receiver tube with carbon fiber.  To do this, I used small bits of 1/4" plywood to "fill in the gaps" between the hull and to protruding tube, and then laid 12 oz. carbon fiber clot over the whole thing.  
The next task was to simply trim off the excess when the epoxy set.

The other big(ger) task over the weekend was to reinforce the seams between the cabin and the deck, and between the cockpit floor and the sides.  In both cases, I used biax tape which I wetted out ahead of time.  All of these seams are "outside" curves (even though they are inside the boat) with gravity as the enemy.  An extra set of hands would have been nice, since it took quite a bit of time to get the tape to stick.  In any case, the reinforcements looked really smooth after they were done.  Once the tape was in place, I then filled in the gap between the cabin and the deck with thickened epoxy.

Bow Prod Extension and Retraction

Thinking a bit ahead, I'm planning on having a very simple bow prod extension mechanism, with a pulley on frame 18 and a line running straight back through the cabin bulkhead to a jam cleat.  I'm planning on having the spin tack line run right through the center of the prod and out the tip (which I still need to fabricate).  The tack line would also double-duty as the pole retraction cord.  The tack line will also run though the cabin bulkhead and will cleat right next to the prod extension line.  Of course all of this may change, but that's the plan for now.