Team Seacats

I broke the mold and fence away from the support structure underneath and flipped it over to being removal of the parting fence. It went relatively easily and I only had to pick out a couple of the green knobs that created the indentation for the other mold half to lock in place with. Some of them didn’t seem to sit flush with the parting board and they let a little bit of gel coat creep in around the edges so I’ll have to touch up the indentations to ensure they have a nice clean entry. The rest came out quite well so far. I have not tried to remove the plug and I don’t believe I will do so until after the other mold half is complete. I noticed that the plug has a 3″ scratch where it was in contact with one of the cradles so I’ll have to touch that up before I get started with the rest of the mold….it shouldn’t be difficult…a little finishing putty, a squirt of clear, a little wetsanding, polishing, and wax and we’ll be ready to go for round two. I’m a little unsure about how to proceed with the clay that is in the seam of the mold – I think I’ll clean it out as much as possible with a pick and leave it like that. The seam between the hull halves will have to have a bit of cleaning up after molding anyway. I cleaned up the really rough edges of the mold using a carbide cutter in my dremel (another dream accessory for the dremel!) and called it a night.
 

Wow, these things are awesome.  Mat Struble, of catamaran fame, wins the Dn ice boats worlds.  You think cat sailors are crazy?

Apparently I can.  As the fumes from the polyester resin apparently started to get to me (not really – it was more likely the 4 hour marathon mold session) I realized as I tried to take a goofy photo, that when I cross my eyes, only one eye moves inward….weird.

Anyway, the first half of the mold is happily setting up.  I started the evening by pre-cutting most of the glass cloth to go down on the mold.  I first started with preparing a layer of thin, 2″ strips of 3.5oz satin weave e-glass to go around the sharp seams of the mold in pieces.  Then I laid out a 16″ X 48″ piece of the same 3.5oz cloth to cover everything.  Next would be several small pieces of 7oz mat cloth laid in random positions followed by some 13oz Nytex woven fabric (that conforms very nicely to compound curves).  Then, nervously, I shot 6oz of Orange mold gel coat on the plug, again swearing that i was going to get a larger nozzle for my spray gun (it’s 1.4mm now and should be closer to 4mm for the thick stuff).  I eventually got it all sprayed and it was probably just enough – I might have been able to get away with 8oz.  I waited about an hour and came back and mixed up a mixture of 2oz polyester resin and equal parts of milled glass fibers and micro balloons until I got about 4 to 5oz of peanut butter consistency goo.  Equipped with latex gloves, I worked this mixture into the sharp corners of the mold where the fiberglass would have difficulty adhering…lady luck had my back and 5oz proved to be exactly enough.
  

  

Now, I took a deep breath, and mixed up 8oz of straight-up polyester resin and I brushed down the entire plug with it in preparation for the full sheet of 3.5oz cloth.  This might have been an error as I had some difficulty getting the cloth in place – I probably should have used some smaller strips.  I did eventually get it to mostly lay down and I started to wrestle with some minor air bubbles in the areas where the fabric bunched on the horizontal surface of the parting board.  After a while with this, I gave up figuring that I could work out the few remaining bubbles in the subsequent layers of fabric (and I was correct).  Next the mat went down – and it went easily.  The last time I tried to make a mold, I got far to stingy with the latex gloves.  This time, any time I was handling clean fiberglass, I would put a new pair of gloves on – what a world of difference.  After the mat was placed, I proceeded to glop on about 18oz (or maybe 24oz) of resin.  I then used my ribbed roller to work out any air bubbles from the mat (what a miracle tool!).  Once that was done, I laid in the Nytex cloth and it conformed perfectly to all but the sharp corners of the stern.  about another 18oz of resin and the Nytex was completely wet and slowly setting nicely.  I had to put a wood strip on the stern and apply some light pressure to get the heavy Nytex to conform properly.  The electric heater will keep the shop warm for the evening while everything solidifies.  This is a painfull process in that you won’t know that it actually worked until you get to the end (and after investing a significant amount of time and money).

 
 

Poly-Vinyl-Alcohol.  I learned a bit about it yesterday.  I mounted the parting board and the hull to the cradles and started working in clay to the seam between the two to give a water tight seal.  It took me a while to work out a method but I finally figured out that if I used my 1st grade “snake making” technique, I could put the snake at the seam and press it in using the rounded nose of a pair of forceps.  I would fold the clay back on itself when the forceps pushed it out and repeat four times.  Then I would press firmly with the forceps to separate the clay, peel away the upper and lower excess, and then run over the small fillet with a razor blade.  It took me about 30 minutes to work up this technique but once I got it going, I was able to fill the seam in about another 30 minutes…it was frustrating work.  

I then cleaned the plug to remove all the clay fingerprints using mineral spirits, gave it another coat of wax, and buffed again.  I was able to find a mushroom polishing pad for my die grinder while looking for buffing alternatives yesterday morning at Northern Tools.  The Partall wax simply isn’t reasonable to buff by hand – it’s very aggressive.

Now that all that was complete, it was time to spray the PVA.  I’ve used this material in the past with relative no problems but I haven’t used the Partall brand (this time, I’m using a wax and PVA that are designed to work together – hopefully separation of the molds will go much easier).  I loaded up my Divelbiss HVLP paint sprayer with about 2 oz of PVA and laid down the first mist coat and let it dry for about 15 minutes.  I came back and shot the first wet coat and about mid-way through, some movement around the shop caught my eye.  I looked up and found the air brimming with whisper thin “cob-webs” of PVA that were drifting around.  For a few seconds, I was mesmerized at how they floated and then I realized they were landing all over everything – including the plug.  YIKES!  I started waving my arms at them catching them in the air but eventually a few found their way onto the surface.  I let that dry for 20 minutes and came back with water and began wiping off the PVA since it had a bunch of these cobwebs in the surface.  I also noticed that there seemed to be a lot of minuscule air bubbles trapped in the PVA and while most would come to the surface and pop, there was some fish-eyes left. 

I researched a bit on the internet and found that the air was probably too dry and that some of the PVA was drying immediately upon leaving the paint gun causing the cob-web phenomenon.  The website I found recommended adding up to 10% purified water to the PVA to avoid this.  I did and the second round with the PVA went much more smoothly…except for the bug.  A damn bug landed on the deck and stuck there.  I tried to gently remove him while the PVA was wet but he started to come apart.  I decided I would get him when the PVA dried.  I came back tonight to pick him out and the moment I tried, the PVA lifted from the plug in an area about .25 inches in diameter.  It also picked badly and left a ragged edge when the bug was removed.  The good news is that the PVA separated very easily from the plug.  The bad news is that I had to remove it yet again and start over. After realizing how easily the PVA lifted from the plug, I got smarter and simply peeled it off instead of washing it with water.

So now, after fixing some of the clay seams that suffered from the repeated stress of waxing, polishing, and spraying, 7:30pm Sunday night, I have another first wet coat of PVA on.  With any luck, the second coat will be going on in about another 15 minutes.

   

The F18 Worlds are really underway now. Our US teams are hanging in there! The team of Robbie Daniel and Hunter Stunzi (last year’s US SAILING Multihull Champions) are getting there groove on and recorded a high point 12th place finish today. This puts them in 10th overall because they’ve been so consistent. Team Tybee, John Casey and Kenny Pierce, finished several races in the mid 20′s but are still lugging around that 78 point DNF (did not finish) from the first race when their mainsheet let go. When the fleet gets to drop one low-score race, they should move up considerably. Ollie Jason and Pat Gilles were getting their game going when they broke a shroud pin and the mast fell down leaving them with THREE DNF’s for the day. Conditions are still rough! Terrific video HERE (I had a hard time getting this to run in Firefox – use IE)

Originally uploaded by Team Seacats.