National 125 Sailing Association

125 Discussion Forum

Please note: This forum is read by a wide group of 125 sailors.
This is not the place for personal attacks or inappropriate comments on anyones race, sex, age or sailing abilities.



Return to the Forum List

Centreboard Layups
Anyone some advice on glassing Centreboards.. I've been standing on my current Centreboard a LOT lately, and am impressed by the bend it takes with my 85kg standing on the tip, without snapping.

I've shaped a new board but am unsure how much cloth would be needed to preventing snapping it in similar circumstances.

Core is laminated WRC only, (no hardwood strips)

I've put a base layer of 300gsm UniDirectional Carbon Fibre on and one layer of 85gsm Cloth over that..

Is that enough or would more be required.

Would like to hear from someone who has broken one and knows how it was layed up.
Ron G7-Dec-2008    Edit    Delete 
Re: Centreboard Layups
Ron. I would put another layer of 200g woven carbon for insurance or assurance. Make sure it will still be under 21mm thick.
Andrew9-Dec-2008    Edit    Delete 
Re: Centreboard Layups
Ron,
Sorry-I can't help you- I've never broken one of mine! Over the years, have repaired many made by boat builders though that contain woven fabrics so this info. may help prevent others wasting some money. WesternRedCedar is easy to shape and Carbon is light but one does NOT HAVE TO USE either (unless you have free/cheap access).
Waterloo's c'board is just second-hand Q'land Hoop pine & Q'land cedar
(whatever was aROUND(whoops..sorry!)for free to make up the width).
But, I never use woven cloth - I used unidirectional glass(top half aprox. and double bias glass over that with careful thought about how you taper off the layers so no sudden end to the strength. Anyone who listened in Junior Science (common sense I suppose)can understand that
woven fabric is weaker because of the 'kinks'(ie. where the fibres weave over and under each other).We don't 'weave' the steel in concrete reinforcing-same thing- AND of course, unidirectional glass and double bias glass are much CHEAPER to buy than woven glass fabric (no weaving of fine fibres -cheaper to produce).Adhesion to the timber and reinforcing fabric is important so Epoxy or Vinylester resin is the go.
John Anderson.

John Anderson9-Dec-2008    Edit    Delete 
sac gucci pas cher

Hmm is anyone else having problems with the images on this blog loading? I'm trying to determine if its a problem on my end or if it's the blog. Any suggestions would be greatly appreciated.
gucci homme
sac gucci pas cher 9-Dec-2008    Edit    Delete 
Re: Centreboard Layups
Good point Johnny. The disadvantage with finishing with a double-bias is if a strand comes loose it will tear completely off (the full length of the strand). This may go around the whole board. Finishing off with a woven cloth ties the fabric together. P.S. forget the vinyl-ester or polyester. The acid in western red reacts with the styrene and the resin doesn't stick. Always use epoxy on western red. I have recently found out that if you want a stiff, strong board you will be better off using a more sturdy core. Three layers of carbon on western red cedar is no match for tassie oak with a light surfboard cloth.
andrew11-Dec-2008    Edit    Delete 
Re: Centreboard Layups
Thanks Andrew, I used to get by in Herons with a couple of Ash stringers in the WRC and then 2 layers of 85g rovings. But the Heron used to come upright pretty quick and as I never let it go right over upside down, but when i've capped this thing with the spinnaker up, it takes a helluva lot of pressure to get it out of the water again.

Added one more layer of 305gsm Uni CArbon, and I'm on my 21mm limit so that's it.. fingers crossed.
Ron Garner17-Dec-2008    Edit    Delete 

Return to the Forum List       Add a message to this discussion
Measurer's Forum
Committee's Forum

  National 125 Association admin