Team Seacats

Team RAF posted some video’s and pictures on their site from their adventure…check it out.

With my new sails sitting on my pool table, I decided I would finalize some of the rigging details in the next week or so. In order to do that, I needed some flat carbon material from which to make spreaders and a mast crane to replace the light-plywood I used for the test. At the same time, I wanted to test out some of the mold release waxes I have before I rely on them in the hull molds (I can continue to use the PVA but it adds almost two hours to each molding cycle). I’ve had two small .25″ pieces of plate glass I found when I moved into this house 8 years ago so I decided to use those to sandwich some carbon in and vacuum bag to a cure. I first put three coats of “Mold Release” wax on each glass plate and then took 5 layers of (I believe) ~5oz carbon fabric with alternating patterns, poured about 1oz of epoxy into the center, padded with polystuffing, inserted into a 1 gallon ziplock bag, and pulled a 20in/hg vacuum on it. After about an hour under the heat lamp, I disassembled the vacuum setup and found the glass was pretty firmly adhered to the carbon. We won’t be using that wax again!

After trying shots of air pressure with no success, I tried to insert a wooden wedge and tap lightly but one of the pieces of glass finally broke. I then resorted to a tool to give the glass a little more incentive; a hammer. After breaking the glass on both sides into pieces, I was able to scrape off the remainder and ended up with a relatively unharmed piece of carbon. It’s under 1/16″ and incredibly stiff – this stuff is amazing. I can probably get away with just three layers for these components. I think in this case, I’ll forgo the waxes and just use a plastic sheet between the glass and the lamination…I’ll get some bigger 12″x12″ glass for the next round now that I know this is viable.

 

Originally uploaded by Team Seacats.

Who is it?…Hydroptere…hydroptere who?….Hydroptere who’s about to put the hammer down on the world sailing speed record – that’s who!

Wow, 47.2 knots top speed now.  The Finian Maynard speed record of 48.7 knots over 500 meters is looking shaky and the 50 knot speed barrier is watching closely.  It looks like they’ve recently installed some high-tech GPS tracking hardware to satisfy the requirements of the WSSRC (world Speed Sailing Record Council). The most amazing thing is that of all the boats that have ever even approached these speeds, none of them can do so in the open ocean like Hydroptere can but wow…if there ever was a problem at these speeds, it’s going to be dramatic for those on board….Stay tuned!  Read more about Hydroptere at http://www.hydroptere.com

We have a phrase that for the time you drive a catamaran hard on a reach and the deck at the bow is just barely above the surface of the water, we get “bow sizzle” as the tip rips through the water at 18knots (20+mph) with a sizzling sound.  This video has some impressive bow sizzle starting about half way through…these guys were flirting with disaster! Most catamarans will suffer a pitchpole (ass over tits) if you drive their bows in this deep – the Nacra 6.0NA is a monster with a lot of reaching sail power and needle bows which make the boat incredibly fast but unforgiving. I really enjoyed the one I owned for a couple of years.

I vacuum bagged the first hull half today and it was a moderate success.  I just couldn’t leave well enough alone and after it had been sitting for a while, I removed the vacuum to attempt to remove a stubborn bubble in the rounded hull/deck lip.  I think that the problem was that there was no loose plastic right on that corner allowing it to press the glass into it.  I was able to make the situation better by removing the vacuum and repositioning the bag, but it looks like I re-introduced a lot of air into areas that had already started to firm up.  The net result was that there are a lot of tiny air bubbles in the lamination.

I tried a modified resin infusion method that I dreamed up in my head – it actually “mostly” worked.  After carefully placing the fiberglass, laying in poly-stuffing around the perimeter, and attaching 1/2 of the vacuum bag, I started with 4oz of resin and poured it in the center of the mold laying a thick stripe from stern to bow.  Then I attached the rest of the vacuum bag and pulled a vacuum on the layup.  The resin did exceptionally well to saturate all but a 1/2 fingernail size bit on the stern – I can correct that by putting a little more resin on that end next time.  The advantage of this method is that it saves some elbow grease in having to wetout the layup and it saves some materials by not having to put a layer of peel-ply over the entire mold followed by a complete layer of stuffing.  The drawback of this method (the same as resin-infusion) is that you are more susceptible failure of the part if there is a vacuum problem.

The picture below is the hull half after I started to remove it from the mold.   The outside finish is actually quite good.