carbon mast numbers

[rob denney]

G'day,

Further to recent posts, we have just completed an 18m/60' unstayed mast for Visionarry, a 15m/50' harryproa (www.harryproa.com).

Some details:

Righting moment: 17,820 tonne metres/58,800 ton feet
Mast length: 18m/60',
Above deck: 16m/53'
Diameter at base: 300mm/12"
Diameter at tip: 100mm/4"
Safety factor: 2.5
Designed weight of bare tube: 119 kgs/262 lbs
Actual weight of bare tube: 117 kgs/257 lbs
Designed deflection with 153 kgs/337 lbs midway along mast: 178mm/7"
Actual deflection with 153 kgs midway along the mast: 175mm/6.9"
Designed tip deflection at capsize: 2.9m/9'8"
Actual deflection at capsize: yet to be established!
Cost of mast painted with top and bottom fittings: $AUS15,000/$US10,800/9,000 Euros
Additional cost for lightweight carbon rcb track bonded on: $2,800/$US2,000/1,680 Euros

regards,

rob

[nero]

The future has arrived ... at an honest price.

Thanks Rob.

[rob denney]

Thanks Nemo. G'day,

Pics of the boat with the mast up are at http://au.photos.groups.yahoo.com/group/harryproa/lst Click on the Visionar... folder. You have to join the group (easy), or you can wait a fortnight or so and they will be on our web page.

Note the carbon rcb track bonded onto the mast.

By the way, Nemo, who is going to build your carbon boom? We would be very interested in quoting.

regards,

Rob
www.harryproa.com

[nero]

Rob,

I will ask you to make the plans and engineer the mast when I get the boat further along. I think my build will be heavy so, I wan to weigh my hulls to get a realistic idea of weight for you to do the calcs with. You have an excellent price for this service (multihulls@steamradio list)

Checked out your strip/carbon method. Creative alternative and since it seems to work, I like it. It will be several months before I can get you the numbers.

nero