Tag Archives: harryproa

Should probably stop…

…announcing new boat designs. I have gone through four designs so far, each time thinking I was done. Well now I am actually done. Pretty much.

Why am I done now instead of being done the last few times? It’s a little to do with optimisation and a lot to do with finding an awesome boat!

Last time I posted I mentioned something called a Harryproa. The interesting thing about this type is the accomodation is situated in the windward hull and the rig is situated in the lee hull. The result of this is greater stability due to the distribution of sail force and weight of passengers. However all the designs I saw were too small and had too small a payload. Until I saw ‘Sidecar’ by Doug Haines, a modified Elementarry Harryproa. I based my design around it, and this is where the optimisation came in. I needed a greater payload available, but I also┬ádidn’t want to waste wood making something fat and slow (like my other designs).

The hulls are 20’x2’x2′ for the lee and 14’x3’x4′ for the windward. The 20′ hull can be made out of 4 sheets of oversized ply with very little waste. The 14′ hull will take a few more regular sized boards, but the accomodation section has been designed with space and ease of building in mind. The whole thing can be stitched-and-glued and there is no complex geometry. I should have about 300-500kg max payload without having to sacrifice much in the way of speed.

Then I designed the crossbeam fastenings, the crossbeam supports and the internal bulkheads. There will be space to sleep two and a 2′ x 2′ x 7′ store in the 14′ hull. The 20′ will have a 2′ x 2′ x 6′ store for light objects. The remaing hull space can be filled with structural foam to make it theoretically unsinkable (touch wood).

All I need to do is design the mast to be stepped into the crossbeams like on ‘Madness’, but I need to see whether that is a good idea. So I’m going to bother the nice people on the boatdesignforums.

Also just got the call yesterday, my school is hosting OFSTED for the next two days…wish me luck!