Carbon Fiber Wind Generator Mast

[zboss]

Hi all,

We are in the process of buying a new boat that does not have a wind gen, which we want to add. Our current boat has a wind gen and a stainless steel mast that is a beast.... weighs a ton.

I was thinking that I would rather go with lightweight components on the new boat since it’s much more performance oriented, including a carbon fiber wind generator mast. However I don’t know if carbon fiber tubes are an appropriate selection for a wind generator or the details on how you would spec out the mast.

Looking for feedback...

-z

[coopec43]

I found a sail board mast on the rubbish dump and brought it home as I have wondered if that would make a wind generator mast. (the wind generators I have looked at are quite light). The mast is f/g, slightly bendy and light-weight.

Maybe that is the way to go?

Clive

[model 10]

We have a large wind generator and it's mounted on a 1 1/2"seamless SS tube with a wall thickness of only .060". It's light.

[Standbly]

I did what you are thinking about but probably in a different setting. The fiberglass (not even carbon) tube I used is about 5ft length and on top of my mizzen mast. It holds an Air Breeze. The fiberglass tube is in a foot which has a supporting 3 inch collar. That's it, no wires or other supports.


It's been up there for 3 years. Atlantic crossing included. I did not worry about the strength of the fiberglass tube at all, once I tested it...

[kmacdonald]

Aluminum would also work. Carbon fiber would be lighter but not as durable or crush resistant.

[Thalas]

Stanbly is right. For smaller items, the difference in weight between carbon fiber and fiberglass is pretty negligible (you just have to make the fiberglass thicker to match the carbon rigidity) while the cost difference is significant.

Now, passerelles, biminis, and other larger structures greatly benefit from going carbon as the weight difference will be larger.

Here's a great video describing the difference between the materials regarding strength and stiffness:

https://www.youtube.com/watch?v=KHXVf0SaJpA

[mrybas]

I laid up a 12’ carbon pole over a 3” PVC pipe that was used as a mold. 3’ of the pole is buried below the deck and glassed to the inside of the hull. I haven’t weighed it, but I’d guess it’s about 15-20 lbs.
The pole probably cost about $350 in material and a couple days of work, but it’s a fairly easy project. I looked at buying a carbon tube, but they were all well over a boat buck.
Another option is to find a broken carbon mast from a beach cat or something with a similar size section.
I have a broken M32 mast that I was as going to use, but looked too large to be esthetically pleasing.

[singlespeed]

Sailboard masts are designed to carry the forces of the sail in decreasing amounts as you go from the base towards the top, with additional rush reinforcement in the expected area of the boom attachment Also for gust control, the mast will frequently be manufactured to be more flexible at the top. Either or both features are undesirable in a wind generator mast. The last thing you want is a wind generator whipping around.

[Bleemus]

I raced across the North Atlantic on a 40' trimaran with an AirX on a carbon fiber windsurfer mast. The struts were made from carbon hockey sticks. Worked fine.

[Luc bulterys]

Interesting ideas !
Anybody can tell us if it is more or less prone to transmitting the vibrations ?

[coopec43]

Originally Posted by singlespeed

Sailboard masts are designed to carry the forces of the sail in decreasing amounts as you go from the base towards the top, with additional rush reinforcement in the expected area of the boom attachment Also for gust control, the mast will frequently be manufactured to be more flexible at the top. Either or both features are undesirable in a wind generator mast. The last thing you want is a wind generator whipping around.

Singlespeed

Looking at the mast I have the wind generator wouldn't whip around as you'd only use the bottom half which would be quite stiff. But I agree with you, you need to keep it as steady as possible.

However many people mount them on top of their mizzen mast - hardly a stable platform in an even moderate sea.

Wind speeds at the masthead can be 50 percent greater than at sea level due to wind shear, so the higher up you put it, the more power you’ll get. Of course, the pendulum effect of a moving boat means that putting a wind generator higher up will increase the effects of pitch and roll

Clive

[44'cruisingcat]

Aluminium tube would be nearly as light and much cheaper.

[zboss]

My problem with Aluminum is the look. I don't want a mashup of stainless and aluminum. I like the idea of laying up a little carbon fiber around a fiberglass pole. What would that layup look like?

[Bleemus]

Why go through all that hassle when it has already been done for you? Get a windsurfer mast and two carbon hockey sticks. Voila.

[bad.wabbit]

Originally Posted by mrybas

Attachment 179998Attachment 179999

I laid up a 12’ carbon pole over a 3” PVC pipe that was used as a mold. 3’ of the pole is buried below the deck and glassed to the inside of the hull. I haven’t weighed it, but I’d guess it’s about 15-20 lbs.
The pole probably cost about $350 in material and a couple days of work, but it’s a fairly easy project. I looked at buying a carbon tube, but they were all well over a boat buck.
Another option is to find a broken carbon mast from a beach cat or something with a similar size section.
I have a broken M32 mast that I was as going to use, but looked too large to be esthetically pleasing.

Nice work. Did you remove the PVC pipe? And if yes, details.