38 sailing hull design

[frank smith]

This is an idea i have been kicking around , it is a radius chine sailing hull about 38' .
Please give some advice or critique.

[TeddyDiver]

It's sooo double ender I don't know which way is the bow How's the hydrostatics?

[frank smith]

Originally Posted by TeddyDiver

It's sooo double ender I don't know which way is the bow How's the hydrostatics?

Yea it is , but i like them for some reason .

Design length : 37.422
Length over all : 37.635
Design beam : 11.000
Beam over all : 11.293
Design draft : 1.750
Midship location : 18.711
Water density : 65.016
Appendage coefficient : 1.0000
Volume properties:
Displaced volume : 274.08
Displacement : 7.955
Total length of submerged body : 34.237
Total beam of submerged body : 9.889
Block coefficient : 0.4626
Prismatic coefficient : 0.5343
Vert. prismatic coefficient : 0.7022
Wetted surface area : 262.50
Longitudinal center of buoyancy : 17.817
Longitudinal center of buoyancy : -2.610 %
Vertical center of buoyancy : 1.052
Midship properties:
Midship section area : 14.983
Midship coefficient : 0.8658
Waterplane properties:
Length on waterline : 34.237
Beam on waterline : 9.889
Waterplane area : 223.03
Waterplane coefficient : 0.6587
Waterplane center of floatation : 17.881
Entrance angle : 18.997
Transverse moment of inertia : 1252.7
Longitudinal moment of inertia : 12716
Initial stability:
Transverse metacentric height : 5.623
Longitudinal metacentric height : 47.447
Lateral plane:
Lateral area : 42.236
Longitudinal center of effort : 18.675
Vertical center of effort : 1.051[ATTACH]38 rd de.txt[/ATTACH]

[frank smith]

the bow is the front part

[TeddyDiver]

A bit too boxy sections for my taste and a bit high Cp.. What's the material? Steel/alloy could have some more rocker and dead rise on the bottom so the rounded chine would be easier to do. For other materials bit more roundnes.
BR Teddy

[frank smith]

Originally Posted by TeddyDiver

A bit too boxy sections for my taste and a bit high Cp.. What's the material? Steel/alloy could have some more rocker and dead rise on the bottom so the rounded chine would be easier to do. For other materials bit more roundnes.
BR Teddy

I was thinking ply epoxy , but the panel shape doesn't work out well.
It is an exercise in radius chine and a barge section, the bottom would be dead flat athwart until the start of the radius , much like a junk hull ,with the idea of shallow draft , maybe twin keel arrangement .

Frank

[TeddyDiver]

Originally Posted by frank smith

I was thinking ply epoxy

A bit confusing. I mean either do hard or multi chines for ply or larger round bilges for cold molded ply strips.. ?

[frank smith]

Originally Posted by TeddyDiver

A bit confusing. I mean either do hard or multi chines for ply or larger round bilges for cold molded ply strips.. ?

Right .The choice of a double ender make a constant radius difficult, but ill move it around . Of course multi chine would make it easier .

Frank

[Easy Rider]

Put a rather large wine glass keel faired in and round out the last 4-5' and it wouldn't be that much different than my Willard 30.

Easy Rider

[frank smith]

BR Teddy,
In keeping with the shallow draft , I think that keeping the Cp around .55 ,
is sort of necessary for the stability.
Frank

[frank smith]

Originally Posted by Easy Rider

Put a rather large wine glass keel faired in and round out the last 4-5' and it wouldn't be that much different than my Willard 30.

Easy Rider

The idea started out as a chine version of Herreshoff ' Marco Polo . Then became radius chine , and shrunk . Ah ,the dangers of a computer program.
But I like the concept . A transom stern would make more sense , but i like the look canoe stern ,when it is right .
Frank

[Eralnd44]

This is simple boat. Have some of this kind in Sweden. Some are good.

[frank smith]

Here it is with changes . I left the lines indicating the area of radius chine .
I am not sure if it is the right way to approach this or not .


new Hydrostatics

Design length : 37.422
Length over all : 37.655
Design beam : 11.000
Beam over all : 11.326
Design draft : 1.750
Midship location : 18.711
Water density : 65.016
Appendage coefficient : 1.0000
Volume properties:
Displaced volume : 236.22
Displacement : 6.856
Total length of submerged body : 32.169
Total beam of submerged body : 9.531
Block coefficient : 0.4402
Prismatic coefficient : 0.5374
Vert. prismatic coefficient : 0.6627
Wetted surface area : 235.40
Longitudinal center of buoyancy : 17.367
Longitudinal center of buoyancy : -4.177 %
Vertical center of buoyancy : 1.071