Friday, May 23, 2014

Goodbye Seacocks

I had planned on getting the cockpit primed and ready for final paint today, but the tiny bit of fairing compound I put on at 5AM decided not to cooperate and still wasn't sandable by 5 this afternoon.  It was raining pretty hard on and off all day and the temperature never really got much above 52, so it's not terribly surprising.  I did put a 100 watt lamp on it, but it just wasn't having any of it.  I suspect the super high humidity hampers the cure time of Quick Fair, or maybe I just didn't add enough hardener in to make it quick in a timely manner.  Oh well, can't win 'em all.

I did make pretty good use of my half day off though, and decided to tackle the last remaining bit of glass work on the boat; the inlet and outlet seacocks for the head.  Back at the beginning of the month I removed the head seacocks and glassed in 5 layers of biaxial cloth in the bevels that I ground from the inside.  I left the outside holes for a later date; today was the later date.

Because grinding bevels is always a nasty mess, I started by tarping the side of the boat where I was going to work and made a mini containment area to keep the dust from getting everywhere.  Once that was set up I went to work with everyone's favorite dust machine, the angle grinder with 36 grit discs.

Before I started, I measured the thickness of the hull at the through hulls and found that it was about 7/8" inch thick.  That's a pretty substantial thickness in itself, but if you take into account the fact that I ground down about 1/2" on the inside to accommodate the 5 layers of cloth I glassed in earlier this month, that is one beefy hull laminate (~1-3/8").

I decided that it wasn't necessary to go crazy with the outside lamination because I had already done 5 on the inside.  I settled on 3 layers on the outside and ground out about a 1/4" deep bevel around the 2 holes.  Since I wasn't going too deep, I still had to contend with the void from the original holes, so after dremeling all the holes and wiping everything down with acetone, I filled them with fairing compound.  Technically, I should have used a structural filler for this, but I'm really low on straight epoxy, but have plenty of fairing compound.  Given that there will be 8 layers total of biaxial cloth when finished, I'm not too worried about the strength of a little fairing compound sandwiched between.

I let that set for a bit so it would firm up and then wet out the three layers of cloth for each seacock hole. I set them all in place smallest first.  I know there is some debate about what is stronger, largest first or smallest first, I don't care.  I like smallest first, it just works for me.  Anyway, once I positioned everything into place I covered it all up with plastic and braced it with cardboard to keep it from sliding off.

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