About to get a new board glassed and a local guy i got a blank off said carbon rails can sometimes hold excess resin and make the rails more brittle and recommended maybe getting extra glass along rails.... i have snapped several boards over the last couple of years so want to make it as strong as possible at the same time keeping it light as possible.....
... any shapers here that have any advice would be appreciated.
I would say from and engineering stand point that it is the carbon itself making the rails brittle....
Fibreglass will flex much better than carbon although the trade off is in the weight...
Just makes the board stiff, won't do anything for impact protection,on a good glass job, you will have enough overlap, if you need as stronger board, it will need extra glass over the whole board
Simply he is wrong. Carbon does not hold more resin. It is more difficult to visualy see if it's wet out enough though. So I guess the inexperienced could use too much resin.
Use about 1/2 the weight carbon as you would glass to get the same strength.
When you know how to use carbon you can make your board lighter, stronger, stiffer or lighter stronger, more flexible.... It really depends on the lay up and shaping.
Don't use the same weights and shaping you would with glass though. You will end up with a super rigid potentially brittle board
in engineering terms when you support a beam at each end and load it in the middle the compression and tension loads are at the outside top and bottom edges. So generally the deck laminate takes compression loads from your feet and the base has compression and tension loads from jumping (flexing).
The centre of a beam is supposed to hold the upper and lower skin apart. This is why you have 'I' Beams and web beams. The centre only needs to handle the sheer forces.
So IMHO carbon on the rails does not really make a board stronger. It could change the flex and fell but this is another thing altogether.
