Aloha Adam,
No worries, just needed a little push.
In the break zone on Vaimana’s mast the windward fibers pulled away from the fiberglass circumferential winding (blue in photo). The leeward fibers folded over. The forward 1/4-1/3 of the mast looks like it has a lot of fiber pull out associated with a tension break (red). The area right behind the mast track also had similar pull out (green).
dismasted freedom 39 ph
Re: dismasted freedom 39 ph
BTW anyone know where I can get some of this aluminum sail track?
Re: dismasted freedom 39 ph
Correction, the above analysis were done with a 500 lb load at the tip not 1000 lbs.
Below is the mast with the factory sleeve and 1000 lb load at the tip. Don’t worry about the red its still about 1/3 of the ultimate strength. These next two are just closer views of the above near the sleeves 500 lb load at tip. No extreme stress areas.
What I see is the fracture zone looks like the load pattern from the model. The two high loaded sides windward (tension) and leeward (compression) collapsed and the remaining smaller forward and aft areas tore. Still not sure what the cause was.
Below is the mast with the factory sleeve and 1000 lb load at the tip. Don’t worry about the red its still about 1/3 of the ultimate strength. These next two are just closer views of the above near the sleeves 500 lb load at tip. No extreme stress areas.
What I see is the fracture zone looks like the load pattern from the model. The two high loaded sides windward (tension) and leeward (compression) collapsed and the remaining smaller forward and aft areas tore. Still not sure what the cause was.
Re: dismasted freedom 39 ph
Everything wears out eventually even us....
Re: dismasted freedom 39 ph
Hi Adam,
Scary story. Glad no one got hurt. I was curious if you were using any running rigging stays when this happened.
Thanks
Karl
Scary story. Glad no one got hurt. I was curious if you were using any running rigging stays when this happened.
Thanks
Karl
Calipso, 1979 Freedom 40 AC #35
Re: dismasted freedom 39 ph
ALOHA Karl, " running rigging." pertains to all the of the lines to control the sails halyards, sheets, ect. freedom boats have self standing masts that dont require any "standing rigging" A
Re: dismasted freedom 39 ph
Adam, Oh, maybe I'm calling it by the wrong name. I have a 1979 FF40AC, new to me. Thats what the seller called them. So what I'm talking about is 2 cables that run from the top of the mast down to about 6ft above the deck and are attached to a fiddle block for tensioning. These attach to the toe rail wherever is good, and you can easily move them around. I heard some people don't use them at all and that it's a matter of preference. I hope that makes sense. Do you still have the same boat and how's everything going?
Thanks
Karl
Thanks
Karl
Calipso, 1979 Freedom 40 AC #35
Re: dismasted freedom 39 ph
Running backstays, I think maybe you mean...?
Re: dismasted freedom 39 ph
Here is a status update for the mast repair:
I cut some samples of the mast and took pictures of the cross sections along and perpendicular to the unidirectional fibers. The wall thickness is about 0.291” thick the carbon fiber portion is 0.215” thick. It appears to be an all unidirectional layup. It doesn’t look like it is a filament winding type layup. There is a thin layer of fiberglass wound around the circumference on either side of the CF. A fairing coat of filler is applied on the outside. The fiberglass layers were easily removed with my fingernails.
5X end grain
5X end grain (There are some voids in the layup seen from the end grain this is about 2” from the break)
5X end grain
I cut some samples of the mast and took pictures of the cross sections along and perpendicular to the unidirectional fibers. The wall thickness is about 0.291” thick the carbon fiber portion is 0.215” thick. It appears to be an all unidirectional layup. It doesn’t look like it is a filament winding type layup. There is a thin layer of fiberglass wound around the circumference on either side of the CF. A fairing coat of filler is applied on the outside. The fiberglass layers were easily removed with my fingernails.
5X end grain
5X end grain (There are some voids in the layup seen from the end grain this is about 2” from the break)
5X end grain