Tired of bothering Mike Daniels with this question even though he has been too patient with me. I am glassing 3 boards, two stringerless and one with a stringer. I typically free lap 6oz S cloth bottom about 2-3 inches on the deck and 2 x 4oz S cloth on the deck freelap 2-3 inches on the bottom. So the rails are actually wrapped with 14oz of S cloth. Eps and epoxy. The boards I have done come out pretty stiff or at least they feel that way. Would it be better to wrap the rails with just the 6oz and one of the 4oz and just use the other 4oz as a deck patch? Would that make the board slightly more flexible?
You can cut the fabric so that you only have 10oz of cloth on the rails at the tail, where you want the flex, and leave the 14oz of cloth in the middle where you don’t want the extra flex.
hey michael
do you do a foiled board. like mike daniel no s does it? do you have a thickness at 0+6+12 inches off tail for us?
stiff comes from thickness primarily
then, i start guessing:
stiffness comes from how much is on the deck, tail side
then from the laps
Two boards, no stringers
6'2" x 19 1/4 x 2 3/8
at 0" 1/2 at 3" 3/4 at 6" 1"
6' x 20 x 2 3/8
at 0" 3/4 at 3" 1 at 6" 1 1/4
MV,
The tails are too thick to give good flex i guess. Your laminate isnt dry and flexible like a coil, so you should even go blow the figures i give you to get sort of the feeling you are after…
my qualifier coil at 6.3*19 comes in at around [tail pad] 1 5/16 [1.31inch] at 12" off tail, and only 9/16 [0.56inch] at 1" Off Tail.
if you dont want to make them thinner stop the deck-lap at the tucked edge and the second deck lap stops at the rail apex
the bottom lap 1 inch onto deck, or less of course: meet the 2nd deck lap at rail apex for more fluidity and easy sanding!
oh, and we want to see pictures too, rocker, foil you know the drill?!
Wouter
be careful trying to foil like Coil... as per MD, you need a really strong build schedule to be able to foil them out that much...
Ordered a board from Mike @ coil which should arrive 4-6 weeks. Not trying to replicate their boards, or any other professional since I am not very good at this. I have just noticed that the boards that I make seem to be very stiff. Certainly stiffer than high end short boards. They are really like tanks(my sons words). I am very squimish about foiling out beyond what I have done for the shortboard shape so was trying to do something different with the lamination to add just a little flex. I also did not want to ask Mike specific questions since I thought I bothered him enough about the coil for me so I turned to you guys. Will take pictures after I finish shaping the funboard for my wife(I can not believe she really wants to surf). The information wouter has given is what I was after. Just wondering if altering how I laminate and wrap the rails will change the flex on the board. I am not competent to do much more than that anyway.
Pictures, not the best it took a while to figure it out.
[img_assist|nid=1050912|title=split rocker|desc=|link=none|align=left|width=0|height=0][img_assist|nid=1050911|title=split|desc=|link=none|align=left|width=0|height=0][img_assist|nid=1050908|title=short rocker|desc=|link=none|align=left|width=0|height=0][img_assist|nid=1050907|title=short|desc=|link=none|align=left|width=0|height=0]
Second try[img_assist|nid=1050911|title=split|desc=|link=none|align=left|width=0|height=0][img_assist|nid=1050912|title=split rocker|desc=|link=none|align=left|width=0|height=0][img_assist|nid=1050907|title=short|desc=|link=none|align=left|width=0|height=0]
[img_assist|nid=1050908|title=short rocker|desc=|link=none|align=left|width=0|height=0]
Exactly!
Assuming you like the thickness of the tail, you should reduce the lap on the deck and bottom. You said 2-3 inches…that’s not necessary. I would do 0.5 inches. The glass on the middle of the rail adds no stiffness. As you get further away from the middle, the glass adds more stiffness. Since the deck and bottom are the furthest points from the middle of the rail, glass that you add there will add the most stiffness. Keep that 14oz of glass on the rail for impacts, but don’t lap it around so much.
There is no way I can do two layers that are oriented 90 degrees to each other which it looked like your research revealed was the best for flex as well as for impact resistance. The width of the glass I have is only 27". I assume S glass will be stiffer than the glass you used in your trials, correct. Would orienting on the bias in two different directions which might achieve 45 degrees be an improvement. Can you make that assumption extrapolating from your data.
When I wrote 0,90
that is the orientation of a standard cloth. 0 refers to fibers in the direction of the stringer and 90 are the fibers perpendicular to the stringer. I did not mean that a cloth is rotated 90 deg. 0,90 refers to the standard cloth that you are using, laid the normal way. With a 27" roll, you can’t change the orientation. You need a bigger roll.
S-glass is only a few percent stiffer than E-glass. S-glass is much stronger and tougher than E-glass. S cloth is not the source of your stiffness. The stiffness would be basically the same with the same weight E cloth.
If you want more flex, (in order of easiest to hardest)
- don’t use a stringer
2)only lap on the rail, don’t lap onto the deck or bottom…bring the laps 0.5" beyond the rail…not 2-3".
3)next time you by a roll of fiberglass, buy a 50" or 60", then start changing the orientation of the fibers.
4)buy cloth weights less than 4 oz…3 or 2 oz cloths work well.
5)Use 2 oz Innegra or 2 oz Skinz in place of one of your 4oz layers, or in between 2 layers of 3oz or 2oz
6)Foil your board thinner
Thanks for the info