- Joined
- Jul 31, 2008
- Messages
- 4,175
Well, I received a request to build a rather large kneel down hydroplane for a fellow member on intlwaters. His is a little different than the others I have built, as its 52" in length, and being built for a zenoah gas outboard with G-Morty lower leg. I have decided with that much weight (He figures about 7lbs for the motor/lower leg) that I need to actually add some weight to the hull as my 41" version weights only about 4.5lbs. To do this, I am increasing the tunnels floor from 1/16" ply to 1/8" ply, The top deck of the tunnel from 1/32" to 1/16", the center formers are solid stock, that was cut to a little over 1/4" thick. The formers I actually like better doing as solid material over ply as they seem to stay more true where the ply wants to flop around. I am going to incorporate that into all my sizes from here on out. I also used some cross bracing where usually only foam is installed in the center former. The transom is also 1/2" thick where previous designs were 3/8" thick.
Tonight the foam for the center will be placed in, and cut to shape and the top deck possibly installed. Today I am pondering weather or not to use 1/4" ply for the cowling sides, or a layer of 1/8" skinned with a 1/32" skin on the outside. I don't want the top edge to look so think that its almost goofy, but I do need it strong as it will take the forward thrust load from the engine.
I am also changing some other designs features. From now on, where the front turn fin brace assembly mounts to the back of the sponson, that rear sponson plate will be 3 layers of carbon fiber and a backer of aluminum plate so that it can be drilled and taped by the owner. I am also adding a wood block were the rear turn fin brace mounts on the top of the non-trip. This will allow the screw to be fully encased in wood..not just the wood skin to foam like previous designs. These things will be done on all sizes of the boats.
Here are some pics of the start:
Tonight the foam for the center will be placed in, and cut to shape and the top deck possibly installed. Today I am pondering weather or not to use 1/4" ply for the cowling sides, or a layer of 1/8" skinned with a 1/32" skin on the outside. I don't want the top edge to look so think that its almost goofy, but I do need it strong as it will take the forward thrust load from the engine.
I am also changing some other designs features. From now on, where the front turn fin brace assembly mounts to the back of the sponson, that rear sponson plate will be 3 layers of carbon fiber and a backer of aluminum plate so that it can be drilled and taped by the owner. I am also adding a wood block were the rear turn fin brace mounts on the top of the non-trip. This will allow the screw to be fully encased in wood..not just the wood skin to foam like previous designs. These things will be done on all sizes of the boats.
Here are some pics of the start:
Looking good!! Chris
