help getting this to work

[Knox]

Originally Posted by Rick Willoughby

It will have a lot of wetted surface. This means it will need a lot of wind to get going.

Have you worked out how much it will weigh and the size of the floats. For any practical use each of the rear floats would need to support at least your body weight. Say 8ft long 2ft deep and 4" thick - or bigger if you are on the heavy side.

It should be soft riding in choppy conditions.

It does lend itself to foils placed below the pontoons but it would draw a lot of water then.

Rick W.

i worked out the size of the floats to be 6 feet long 3 feet tall and about 3.7 in think and i am 148 lbs
were can i find the weight of aluminum tubing?

[Guest625101138]

Originally Posted by Knox

.......
where can i find the weight of aluminum tubing?

I went for 8ft because that is the standard length of foam sheets. May as well go as long as you can as it will reduce wave drag and there will be a good amount of both viscous and wave drag.

Aluminium has a density of 2700kg/Cu.m,

40mm tube 3mm thick weighs 0.94kg/m. This around what you will need at a miniumum.

Rick W.

[Knox]

Originally Posted by Rick Willoughby

I went for 8ft because that is the standard length of foam sheets. May as well go as long as you can as it will reduce wave drag and there will be a good amount of both viscous and wave drag.

Aluminium has a density of 2700kg/Cu.m,

40mm tube 3mm thick weighs 0.94kg/m. This around what you will need at a miniumum.

Rick W.

8 foot is a good idea now that i think about it on the fact of saving money!
so only 3 sheets insted of 6 cool
new card board model to come

[Knox]

2nd model
http://imgcash2.imageshack.us/Himg17...=640&ysize=480
http://imgcash4.imageshack.us/Himg17...=640&ysize=480
http://imgcash3.imageshack.us/Himg17...=640&ysize=480
http://imgcash4.imageshack.us/Himg17...=640&ysize=480

displacment with hulls all the way in the water and 4 in thick
#1
160.83 gallons
#2
109.72 gallons

[Knox]

what if you made the bow hull 8 feet long insted of the 6 feet long that would stop the frount from going down as much

[Guest625101138]

I am not making anything.

You need to decide the design parameters. I thought 17kts would be reasonable. If you want to go faster than this then there are better configurations.

Rick W.

[Knox]

Originally Posted by Rick Willoughby

I am not making anything.

You need to decide the design parameters. I thought 17kts would be reasonable. If you want to go faster than this then there are better configurations.

Rick W.

i know i am just thinking online

[Guest625101138]

Knox
I believe you have a workable concept.

The next logical step would be to set out what you want to do with this boat. Things like its intended purpose, the estimated displacement, target speed, target weight, budget cost etc.

Once you have this you can build a scale model to better appreciate the construction challenges and observe sailing performance.

Rick W.