From comparative analysis we have found that 18 kg's per homebuild F12 hull is possible. This number comes from measuring an actual homebuild hull of slightly longer length but the same building principle and simulation analysis using PC software.

Other top boundery weights have been determined (measured) as well. A short listing will be given now :

2 hulls : 2 * 18 = 36 kg
1 unstayed alu mast = 10 kg
7.0 sq. mtr. sail with full length battens = 4 kg
2 rudders and rudderstocks = 4.5 kg
2 alu beams = 4 kg
2 push rods = 2 kg
rest (small stuff) = 4.5 kg

Total 65 kg ready to sail.

Bare platform (hulls, beams, trampoline) will be under 45 kg and thus under the 50 kg weight limit for roof racks on small cars.

These limits allow for some weightsavings here and there, but as this boat is intended to be homebuild by a large group of amateurs I feel it is best to stay conservative. No exotic materials are used. Ply/epoxy or plain glass/foam, aluminium, dacron or maxx pentex and some stainless steel bolts and fittings.


The major dimensions appear to be :

3.75 mtr in overall length
2.00 mtr wide
65 kg ready to sail
5.9 mtr tall mast aluminium and homemade from high strength alu tube
7.00 sq. mtr. high aspect sail (aspect = 3.8)
5.15 mainsail luff length
1.85 mtr alu boom
Quite a lot of trampoline area.


Texel handicap with 40 kg person on board = 135
Texel handicap with 60 kg person on board = 142

(Wave = 141, Hobie 14 = 135, F18/F16/A-cat = 101, laser-1 = 160. laser 4.7 = 173)

A different analysis method shows slightly higher performance and indicates the feel of the craft is much like a F16. Same sense of pitching and heeling. That is a good achievement as the shorter the hulls the more twitchy a boat design becomes. The F16's feel lively but not overly nervous of twitchy. I don't want to push it any further then that as the short hull length is already limiting the total amount of sailarea and with it the F12 performance to the rear of the cat fleet.


Trying to get artist impressions ready to show the world.

Now the detailing of building the hulls needs to be done.

Wouter