Obsessed

I've spent a lot of time this week working nights to get the cockpit done and I'm happy report that as of 9 PM last night, I officially completed the cockpit lamination schedule.  I still have to fair the deck, but no more big layups.  In fact, I can only think of 3 small spots where I need to cut and laminate any more cloth on the boat (Rudder bolt pocket and two seacock holes when I removed the head).

Last October, just before it got too cold, I had done 2 lamination in the cockpit on everything except the area immediately surrounding the rudder.  Knowing that I had to tie everything together later on, I staggered the lamination so everything would fit back together when I resumed in the spring.

Fast forward to last week: I finally epoxied in the rudder post and fiberglass plate and added the bits of balsa core required to fill in the gaps.  The next step was to tie in the fiberglass plate and rudder tube into the existing lamination I did last October and to bring the height of the plate and balsa up.  It wasn't a large area to do, but I did each lamination separately because I wanted to make sure that there were absolutely no voids here.  This is a good place to do things right.  I weighted each lamination down after laying in with sandbags to get everything flat and avoid bubbles.

Now the entire cockpit sole was at the same height and ready for the final 2 layers.  First I mixed up a batch of epoxy with Aerosil and glass micro-spheres (for easier fairing) and filled in any seams and did some minor leveling.  I let that kick off and then, just to be sure, I added 3 layers of 4 inch (9 ounce) tape to the rudder tube and fiberglass plate.

The third layer is a patchwork of leftovers

The next day I did a quick round of fairing to make sure everything would lay flat for the final layups.  Once that cured, I sanded the whole shebang down before proceeding.  I had mostly run out of my 1708 biaxial cloth, but I had a bunch of 'remnants' lying around so I decided to use those for the third layer.  In retrospect, I should have waited for the new shipment of biaxial cloth to come because it would have saved a bit of work, but I wanted to move forward.

The final piece of cloth

I let that layer harden up and filled in the seams with another batch of Aerosil and micro-spheres.  A final sanding the next day and I was ready for the final layer (FedEx had literally delivered the new roll of cloth 15 minutes before).  I decided that I would do the final layer with one large piece of cloth.  It's a pretty big area, so it was a bit of a challenge even cutting it properly, let alone laminating the whole thing at once.  It was fairly warm and I have fast set epoxy so knowing that this would take a fair amount of epoxy (~30 ounces), I would have to do it in several batches or risk having the pot kick before I could spread it.

I mixed up 16 ounces to start and folded up the big piece halfway toward the aft end of the cockpit.  I normally wet out the cloth before placing it, but this was just Way too big to do so I spread out extra resin with a notched spreader on the forward half of the cockpit before laying the cloth in it and smoothing it out.
I did the same with the aft end, only this time I folded the half forward and put down the epoxy.  I laid that end down and smoothed everything out. The 1708 is very good at being flat so it wasn't too difficult (the same can't be said of 1708 going around curves).  I poured out the remaining 5 or so ounces and spread it out with a flat spreader, paying close attention to getting it into the corners and edges.

I quickly mixed up another 12 ounce batch and poured the whole thing out on the cloth and spread it around evenly.  It took a bit of work, but the final 12 ounce fully covered and saturated all the cloth.  In the past I have 'over-saturated' cloth at times by using too much epoxy, causing it to basically float on the epoxy, but this time it was just perfect.  It figures I'd finally get good at it when I'm about done.  By this time it was 9 PM and I was whipped, so I shut off the lights and went to bed.

This morning I woke up at 5 to check the layup and found that it had hardened up nicely and seemed perfectly flat.  All the 'pre-fairing' I did to level things out and fill seams really paid off.  I mixed up a small batch of Aerosil and micro-spheres to a mayo consistency and spread it out to fill the weave.  I'll need to do a few minor rounds of fairing around the edges where the cockpit sides meet the new cloth and around the scuppers and rudder post, but after that, I am good to go for priming the whole cockpit and moving onto a new project.  All told, there are 4 layers of 1708 biaxial cloth (~1/4") on top of 3/8" balsa and a 3/16" bottom skin.  This cockpit is going to be very stiff.