I’m about to vac on my skins. Do you guys think bamboo veneer needs glass as a backing?
I’m going to do 2oz backing on the deck. Should I do the bottom with 2oz glass backing?
Schedule(Top–>Bottom):
6oz eWarp
1/42 Bamboo
2# Foam Core
Bamboo
1/42 Bambo
6oz eWarp
Maybe 4oz eWarp instead of the 6oz?
I’m going for high strengh/low weight. Board is 6’2 x20x2.5 swallow tail hp quad.
Thanks,
Josh
Weekend club comp - creased my 2oz/boo/4oz top 1.5lb stringerless 4 oz bottom . Both rails are split, so it’s a terminal case (still - it lasted the final taped up). It was a sub 3kg (6lb) board including deck grip and fins. Didn’t weigh the glassed board but it was liiight (maybe sub 5lb). 4th session on the board - bummed because it was a lively little thing.
Next one will definitely have 2 layers on bottom, but no boo yet (not ready to go back to that level of stiffness). I want 3 layers on the rail in future to cope with the flex.
Also broke the nose off second surf (what do you know - rocks **are **stronger!). Surfed it taped up. Pretty sure the boo split then because I can see a split now I don’t remember before.
As I have perhaps said before, or perhaps not, just intending to say so and thinking I had, but obviously not sure or I would be more firm in my statement, yes. That is yes, then no. For your two questions.
OK, seriously, essential for under the deck, not so much the bottom. It does add some unwanted weight but I think the bamboo needs some sheathing top and bottom where you put point loads (your feet and in particular your heels). Bamboo will split . Bert was pretty clear about saving weight by just using patches of glass here and there for durability. My next bamboo will follow this idea. Its really easy just to stretch out the roll of cloth and cover the whole board, but you have to ask youself, where do I really need it? Makes you think ahead. I need a patch under my hands about mid way on the board on the rails because for some reason I am alway pushing down at those points as I settle in on the board.
Oustide bottom only needs 4 oz. Just to cover the bamboo, and thick enought to avoid sand throughs.
And another thing. Bamboo veneer, unlike most other veneers, is a big warp layer of fibers running north and south. Not just cellulose fibers in all directions like some others. I like the idea of encapsolating the fibers from the inside and outside. If I am right, even a little cloth/resin on the bottom dramatically strengthens the package. Albeit with added weight. I have some 1.5 oz I use on the inside. Who knows? Maybe its enough.
Just my 2 cents.
I’ve also had bamboo split,glassing was deck 4oz,bamboo,4oz.1 pound eps,bottom glassed bamboo,4oz.The tail split right in the swallow on a chest high glassy day with zero wipeouts.1 bamboo board is plenty for me,I’m moving on to something else now.The stuff looks awfull if it takes on water too…The deck is holding up well though after lots of airs and floaters,lots for a florida boy any how. 
Hmm,
I am worried about cracking and weight. I’m not so concerned about reaching feather weight but I also don’t want a stiff and dead ride.
My thinking was to use bamboo veneer top and bottom to achieve the magic flex pattern.
But, does the bottom veener need backing? Does the bottom even need veneer?
I’m using a 2# core, but my nose and tail are pretty thin.
Thanks for the pointer on reinforcements. I have some unidirectional kevlar. It’s 2.5oz. I failed at wrapping the rails on another project. I could use it for hands and tail patches.
Water stains are a concern…
The top veneer is cut and backed with 2oz. It’s going in the bag soon!
Thanks!
1.5oz +4 oz Bottom no Bamboo
1.5 oz + Bamboo + 4 oz
Im gonna agree with surfding here… no bamboo bottom. That will def free up the flex a bit. As long as the deck isnt perfectly flat, the bamboo on the deck will give it enough stiffness imo (more dome = more stiffness). Im going to be starting my next build in a few weeks, 4oz/bamboo/2oz deck and 2x4oz bottom. Im glassing the bottom double 4oz because I want at least 12oz wrapping the rails, and the 2oz backing on the deck will not be wrapped. Either 1.5 or 2lb EPS… not sure exactly which one.
I'm assuming that your shaped core has a stringer. I did a 6'6" marko with 2lb with a stringer and went with Greg's big wave glassing schedule. Deck to bottom as 6w, bamboo 1/42, 4w, core, 2oz, bamboo, 4w. The board came out heavier than a 6/4 deck 4 bottom poly and stiff as a rock.
I'm just finishing another 6'6" that is 4/4w bottom, stringered 2lb core, 1.5oz, bamboo, 4w deck and it feels much lighter. Prior to glassing the last 4w on the deck and before the sanding coat the board is already 5.5lbs. The bamboo with just the 1.5oz under is stiffer than the double 4 bottom on the finger push test. I would suspect that one could do without the glass backing except in wear areas under the bamboo to save on weight. The bamboo even at 1/42" is pretty damm strong.
“The bamboo even at 1/42” is pretty damm strong. "
That has been the issue for me since the beginning. It’s too strong and too stiff. For our purposes, we need to keep it from spliting in the susceptable areas, keep it sealed from the water, saturate the fibers for strength, and get it bonded to the core (another reason to use glass under). You have to get creative in how you do that. Maybe 2 oz glass outside deck and bottom and don’t use a power sander.
I've had about 20 surfs on my first boo and it's holding up ok, but don't do the airs.
It's 6' x 19.5" x 2" thick. 4oz deck patch, 4oz, boo, 4oz, 1.1# eps, 2oz, boo, 4oz, and 15 mm balsa rails. 2.4 kg or 5.3# without fins, and moderate level of flex.
Just glassing a 6'4" roundtail with a denser core and less glass. Didn't use glass for the bottom - it has a cellulose backing so I'm hoping that will minimise risk of splitting.
4oz deck patch, 4oz, boo, 2oz, 1.5# eps, boo, 4oz, and 15 mm balsa rails.
Expecting it to come out the same weight as the first one, but it feels stiff already. Should've left out the balsa rails with the 1.5# eps.
I've made and surfed a bunch of boards with the bamboo bagged directly to the foam (no backing), and glassed with bamboo fiberglass with no splitting or troubles. But, I have one board that did split from a knee impact.
That being the case, it's best to back up the bamboo with something to save trouble.
_4 oz._
_Bamboo Veneer_
_2 or 4 oz. (your choice)_
EPS CORE
_Bamboo Veneer (Optional)_
_4 or 6 oz._
~Brian
Here is another wildcard, check out my blank:
3/16 BassWood Stringers at 14" apart, this leaves 12"+ of nose and tail to flex. Not an orginal Idea, I know, and I found out Slater snaps his version regularly. He had like 50 built, because he loves them.
Starting to lean towards:
Schedule(Top–>Bottom):
4oz eWarp
1/42 Bamboo
2# Foam Core
Bamboo
1/42 Bambo
4oz eWarp
But this leaves me with 8ozWarp rails. Is that strong enough?
The blank is basic however highly functional!
I’m a little skeptical at this point of the two rail stringers,
At this point I want to keep the weight down to the point it is as durable and lasts longer than my 6/4Top 2#EpsCenterStringerCore 6oz bottom builds. They come in at around -/+ 7pounds with fin boxes, tail pad, leash plug. Very rough calculation…
The shape came out nice! Rail stringers are hard to shape. I’ll be covering them up for sure.
The board shaped clocks, in at 2.5 pounds. With the top veneer backed with 2ozE before Vac/Resin 2.75 pounds.
If I back the bottom with 2oz for strength I’d be roughly at 3 pounds minus epoxy. Room for 3 pounds of resin, cloth and hardware.
I have procured a Greenlight goretex leash plug!
I’m going into the archive to speculate on #'s for 6oz/4oz numbers.
Anybody want to comment on how much resin bamboo veneer sucks up? Should I pre-coat it with epoxy? Will this help with splitting? Please share…
In the spirit of sharing here on Swaylocks, I present the future of rail tools:
Patent pending…
Never would have thought of bringing legos into it… i like your creativity! Very cool, you are light years ahead!
Does the veneer have a backing or is it straight wood? Use a hardboard roller and jusr put enough epoxy to cover the wood, don't saturate. The vac bag will squish it all together.
One of my other comments a ways back on these things is to do the super 77 spray adhesive on the wood to hold the glass in place, cut the wood out then roll out a minimum amount of epoxy onto the glass...you not putting that much extra weight into the board, and if you dont run the cloth out all the way to the rails your not stiff'n the board up that much..You are adding sheer strength, and flex return.
Don't sweat the lack of rail glass. This will only come into play is some one hacks you real bad?
I think if you look at the some of the posts from the wmd thread most people using the 2lb eps with stringers found the boards to be too stiff with top and bottom bamboo. The use of the innegra cloth that some are using on the bottom sounds like a good durable lightweight alternative to the bamboo while keeping the flex and dampening right.
cj
That is awesome. Thanks for making my day.
My bamboo veneer has no backing. The song remains the same, should I use Bamboo veneer on the bottom? And if so should I back it?
Whats the benfit of just doing the deck?
resinHeaD your the one who got me into this mess!
Burn the bottom bamboo to keep warm and use innegra for the bottom.
Please don't do anything I say because I'm the biggest hacker on sways.
Take resinhead advice.
Were did you get your board cnc'd?