Beefing up a directional board

[TomAUSTRIA]

Hi,

I've had issues with boards cracking in the front foot area. For my next board I was thinking of reinforcing that area by glueing on a sheet of epoxy/carbon and then glueing on a traction pad over it.
Has anyone done something like this? Did it work?

Also, any recommendations for board builders who could do such a reinforcement job?

Thomas

[Kyle]

I have completely re-glassed/carbon'd entire surfboards to make them kite-able. There are two issues behind surfboard failures while kiting:

1) Impact. Landing after a boost or bouncing over chop can cause dents from the impact of your heels or balls of your feet. This causes failure of the low density core material, and eventual disbond between the core and facesheet. The disbonds will ultimately grow, creating stress concentrations where the board has not been damaged and eventual new failure initiation points. Anything you can do to distribute the impact loads over more area will help, but you would have to add more than a single ply of carbon or glass to really resolve the problem. The out-of-plane stiffness/strength of a single ply is really low, that's why most kite-specific boards use thicker laminates, such as bamboo, and why they are so heavy. A traction pad will certainly help, along with thicker-soled booties.

2) Bending stress. A surfboard will undergo cyclic loading under bending. Depending on how you hard you boost, or land, the top sheet will go into compression (before boosting) and tension (landing). These loadcases will depend on the surface of the water, your weight, your style, etc. Composites are really good in tension, but not so much in compression, and ESPECIALLY if they have delaminated from the core material. Think of lots of little fibers... you can pull on them, but you can't push (they simply buckle). That's what's happened to the topsheet of your board after you've failed the bond between the top sheet and the core due to impact.

I don't have access to a shop anymore but even if I did, am probably out of the board glassing business. I have found modern kite-specific directionals worth their weight in gold having spent too much time glassing boards and not enough riding, or without a board completely because I cracked it:) If you're breaking kite-specific boards, I'd find a new brand or ask for warranty replacement. But if you're breaking surfboards, it's probably not worth the time/money to make them work. But if you want to ride strapless, and appreciate the lightweight boards, you'll just have to live with braking them. I have a friend who's found it a lot cheaper to just buy used surfboards of Craigslist every 6 months than buy a kite-specific model new.

[Sandman_510]

IMO you dont really want a stronger board. Better that your board breaks than your knees or ankles.
Instead put extra cushioning on board even on top of stock traction pads. NSI sells nice ones; the dual density are quite shock absorbing. Or just use a mousepad. Rubber cement is the right material to bond it.
Better yet: work on feathering your landings. Softly and tail first.