Day 7
Days remaining: 227.

Boat build update.  Peace of Mind.

Well the first Blackbird is coming on just fine.  All of the assembly drawings are done, control systems designed, hull coming together nicely..... But the weight jitters have already started! My target was 28kg or so, but after a quick chat with one of my design guru's, anything around 30 will be more than good enough - reminding me that in Moths, the weight is less critical than one might imagine (provided it will take off!) as once foilborne, the hull weight is part of the righting moment.

The jitters are maybe as I have been criticised in the past for making a boat heavier than it needed to be (even though it was very competitive in it's class and I was proved to be right* ;-) ) and it is always a dilemma. By which I mean matching the desire for a light boat to the need for stiffness and strength - and longevity... I mean, this blog might only have 227 days left, but want to take this boat to Australia in 2014 and beyond!!

The construction of Blackbird 01 being carbon on Nomex is a blessing and curse in this case. Super strong and stiff and very light -  but if the skins LEAK water into the core, the Nomex Honeycomb cells will become saturated and that will be the end of that!

So I have just taken the step of sacrificing 220g of resin to paint the inside of the hull skins before they are assembled to make sure they don't leak and so that they remain totally watertight... I am glad I did because though the skins were properly consolidated and vac'd down, it was obvious straight away that there was some porosity (common in thin laminates and the inside skin is less than 0.5mm).  Only in a few places, but enough to have been an issue.. 220g for peace of mind is a very small price to pay I think...

The other thing that makes me think I am sure this is the right thing to do is this. The inside of the tanks and mouldings are usually peel ply surfaced. Over time boats develop leaks, or water gets in one way or another... Peel ply surfaces seem to me at least to hold a lot of water, whereas shiny resin coated surfaces don't... So I'm going to take a little time, and make absolutely sure the inside skins in particular at this stage are coated, sanded back and coated again until they are 100% tight.

Not sure I'd do that with a foam core boat, but this isn't foam... It's a fragile paper honeycomb, made by the Nomex Bees...

Like I said - a blessing and a curse.

*I'm not going on about it here.. Ask me over a beer when I'm old!