The board I’m planning will be 6’ish webber fatburner shape using a 1# eps foam blank,and 1/40" bamboo veneer deck and bottom,1/16" parabolic stringers with PU foam rails.What would be a good durable glass schedule that doesnt sacrifice too much flex?Are the stringers necessary?I was thinking for the bottom going eps,4 oz,bamboo,4oz lam.Then for the deck eps,4oz,bamboo,6oz lam,and no stringers.Will the deck dent easily with that glass schedule?Will the board snap like a twig without the parabolic stringers?I’m going to start this weekend and will document the build,and hopefully share my adjustable rocker table design,I am very stoked.
Jesus, praise be your name.
I am finishing this same board as we speak.
You are on a great path…look what Allan Gibbons does…it’s unreal what you can achieve
with this recipe.
With veneer on the top and bottom you’ll already have built in some good rigidity without
stringers, parabolic, perimeter or otherwise.
This is further reinforced by a strong glass schedule.
If you get a good full lap to the borders of your bamboo veneer (that’s how I get things
flush without sanding down the veneer edges), you’ll have 18oz of cloth on the rails;
As a reference I have about 15oz on my rails comprised of 8oz tape and 3 layers of 2.3oz
cloth. they still have a little give (without postcure). The extra 3 oz will be even tougher.
Jesus,
I am in the same boat with a 7’10†mini longboard for the woman. I have 1/8 bass for parabolic stringers but don’t want to use them if not needed. I also have 3mm corecell I was thinking of for the deck with bamboo for the bottom. I built a “half pipe†rocker table from 2x4 scraps and MDF but would be stoked to check out your adjustable table. If I don’t hear anything about the need of parabolic stringers by the weekend I am going to glue the PU on without the stringers and see how she holds up.
Have fun and take it easy
no that’s an over build.
they were built without any additional rails or veneers or stringers years ago.
if you’re bagging see if you can wrap the wood around the rail and you can skip the whole rail thing.
Just shape it
bag your skin around the whole board including the rails
then glass by hand like a normal board
simple simple simple
CMP’s been doing it with 3/8"-1/16" balsa over PU and EPS for almost 15 years
he tried to show me the path years ago
but I was a sunova beach
every compsander eventually discovers the importance of KISS
I’m with Oneula. That Bamboo, when sandwiched between fiberglass and saturated with resin is pretty strong. I’d go no heavier than 2 under and 4 over on the bottom and 2 under 6 over on top. For 1 lb EPS maybe some carbon patches under the bamboo for your feet. I’d also skip the perimeter stringers if you are using PU on the rails.
For another data pt, I have a 6-6 bamboo with balsa build up rails. 1 under 4 over on the bottom and 1 under and 4 over on the deck with 4oz tape on the rails and carbon patches. the board is a smige over 2 inches thick. 1 lb EPS. Very stiffy. My 170 lbs can’t get it to flex. No pressure dings. Can’t pinch it with your fingers. Probably over built, but you need some glass on the outside to protect the bamboo and enought to avoid sand throughs.
Good luck. Post pictures. Tell us how it goes.
The info all of you provide is much appreciated,once the table is up and running this weekend I will post pics,it will be far simpler than explaining it,even though its very simple.
Nice input fellas, much appreciated.
Jesus, I am looking forward to checking out the table.
oneula
any chance you share information on how to cover rails with bamboo veneer, or balsa for that matter!
thanks
wouter
okay
for Balsa
(I totally credit CMP for teaching me the balsa technique below)
A. Building the deck skin
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sort out your balsa panels and set aside the most flexible ones for the rails usually it’s the usually ones with the finest grain
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use 1/16 for the rails 3/32 will do too uses 1/8 or 3/16 along the center of the deck for strength.
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build out your skin close to the rails maybe 1 inch from the edge
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take your flexible rail panels and working from the center line them along parallel to the rail and place them on top of your deck panel and trace their straight edge along the taped up deck panel witha pencil(don’t use a marker).
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using a razor cut the deck panel to the pencil line sanding as needed to keep everything tight and attach each rail band to the deck panel with tape.
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make sure you have clean joints of the rail bands as you attached them side by side this is done by a little hand sanding.
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also make sure as you bend the rail band panel along its grain that it wraps around the rail and overlaps the bottom
B. bag on your bottom deck skin with enough extra so that it overlaps the rail line a tad
C. hand sand the overlap tapering the rail curve into the bottom skin lap
D. bag on the deck skin lapping the bottom skin tapered lap
E. remove the over lap by hand sanding it flush to the bottom with a block
you may get crack in really tight curves so make sure you use a razor to slice in relief cuts to prevent cracks but if you have any, cut them out with a razor after and epoxy in a patch. Slice the relief cuts taking out material as need bend the panel around the curve and check the fit. Do this all along the nose and tail
now hand sand the skin all nice and smooth and glass it…
for Veneers
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Bag on the bottom skin using the same technique as you did with the balsa keeping the overlap to a minimum to prevent sanding
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build out your desk skin with an overlap similar to how you would laminate your board with fiberglass. use scissors to cut in relief cuts like you would do with a real thick lam
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cover your board with plastic to protect the foam deck
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lay your deck skin on top of the plastic pinching the nose and tail down with some good green tape
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now spray a thick layer of commercial or homemade “veneer softener” along the rail over hang until the veneer “falls” over the rail like cloth.
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place some absorber paper towels over the wet veneer and make run wrap of plastic stretch wrap around the middle of the board to hold your deck skin in place the put it in a bag overnight. There two options here:
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when you pull the board out of the bag your veneer should now have the compound shape of the deck molded into the skin. You need to careful remove the “shaped” veneer from the deck and the re-bag it on with epoxy and fiber glass or just Pu glue.
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carefully trim and sand the top/bottom over lap flush and then glass as normal.
one option is to not cover the board in plastic and place layer of epoxied glass under the veneer before spraying the top with softener. The softener should not affect the binding of the epoxy and will allow the skin to “fall” over the deck rail. Normally veneer softener is just soapy water that relaxes the fibers in the wood.
I’ve done both
the balsa method is the simplest even with patching.
I don’t know how surftech does theirs but the probably use heat with liquid to saturate and soften the veneer and vacuum pressure from a bag or a mold.
saturating with epoxy with soften bamboo veneer and turn it into a cloth-like fabric
Oneula
stoke IS available without surf today - i feel good after reading that post!
thanks, i will definitely try the veneer version first…
Wouter
For Balsa, we learned from CMP to make a full skin from 4" wide strips of 1/8" or 1/16" using tape. He would line the sheets up starting in the middle and work to the rails. At the rails just fold the balsa over and mark it, then cut it with a razor. When you bag the balsa onto the board tape the areas where the sheets meet the rails down to the board to keep them together. There will be places where the balsa doesn’t wrap just right, so you just make small repairs there.
For stiff veneer sheets, it’s helpful to make a pattern with butcher paper or heavy wrapping paper. Use the paper to figure out where you’ll need relief cuts in the skin to make it fold around the complex curve of the rail.
Then when you bag the skin on, make sure you tape it down to keep it from moving. We cut the inner glass about a half inch inside of the skin. Put the glass on the skin, then brush or squeegee on the resin, then tape the skin to the board. Then cover it with a plastic sheeting and get it in the bag.
It’s very hard to make a sharp over lapping rail edge with a stiff skin, but you can add that on later. I think this is why most people don’t wrap the skins around the board.
FYI… I have a couple of 1lb balsa skinned boards that are indestructable by surfboard standards. I’m sure that Pipe could snap them, but if your head or other body parts hit the board, the board will not have any signs of an impact. You might have a nasty bruise or bump, but the board won’t have a pressure dent.
I don’t know if the thin bamboo veneer is the same. I think the way the balsa gets impregnated with epoxy resin during the bagging that creates a really strong hard skin. Multiple layers of thin bamboo veneer would be that strong, but I don’t know about a single layer. We do use the woven stuff alot and it’s really hard, but it’s also got spaces where the weave overlaps, so when you glass that, it’s not a super flat surface. You may need to put on a thicker sanding coat to get it nice and flat again. I don’t mind the little indentations, but these are my boards, and not something I’m trying to sell. I can’t be sure, but I think the disturbed surface has less resistance
here’s some pics first of all basic balsa deck wrap
Nose
after bag patching a complex curve
don’t worry it all sands down smooth
here’s a veneer wrap using purpleheart
Quote:
stoke IS available without surf today - i feel good after reading that post!
well put
Jesus, some simple rules of thumb.
The softer and springier the foam (#1 eps), the thicker stiffer the skins.
The firmer the foam (#1.5-2 eps), the thinner flexier skins.
The main prob with #1 is that it depresses much easier, more depressions, eventually more failures.
For #1, a 1.5-3.0 mm thick skins is the go.
Generally, your board thickness and foil determines board flex and your skin schedule
Too much flex, more failures.
Just the right amount, great perf and feel, less failures.
Strong stiff boards can last a long time but dont feel as good to ride.
But ride quality is mostly dependent on the quality of waves anyway.
I’d rather ride an avg feeling board in great waves, than to ride a great feeling board in shitty waves.
IMO, design is more important than construction, but its best if you can nail both.
Oneula is dead nuts accurate…KISS.
IMO, vac baggin is the anti-KISS.
But if you have the time, money and motivation, vac baggin is interesting and fun.
Quote:
If you get a good full lap to the borders of your bamboo veneer (that’s how I get things
flush without sanding down the veneer edges), you’ll have 18oz of cloth on the rails;
Afoaf, you’re lapping your inside cloth too?
Onuela and Sharkcountry, great stuff. That first pic of the cracked balsa is what I imagine when I think off wrapping the rail in the bag, but it looks nice when all sanded down. Got me thinking again…
yeah sorry Jeff that was from my second build in 2004 before we got wise and realized it was smarter to not build a complete flat panel and then try and bend across the grain(although you see it can be done) versus keeping the deck panel inside the rail and adding on the rail pieces PARALLEL to the rail so you are wrapping the panel around the rail ALONG THE GRAIN. You just need to kerf cut with a straight razor the rail panels for a flush end to end fit. Much faster than trying to build out a solid wood or wood/cork rail out of 1/8"-1/4" strips like we all have been doing…
Balsa is so easy to work with and clean up its just too bad is so water/resin thirsty turning black when it get waterlogged.
Cedar/Paulownia/Cypress/Bamboo seem to soak less liquid but blue XPS soaks no liquid…
Its even faster if you just cut out your full rail band out of high density PU or Airex/Precision/XPS foam and attach an entire 1" thick rail strip with 5 minute epoxy.
I guess I’m getting lazy these days as there’s better things to be doing with your precious free time (like family and actually surfing) versus working like a compsand maniac all weekend.
dave
kind of funny you’re last comment.
I figure a minimum of $25,000 to $40,000 I’ve thrown away in materials and equipment these past 4-5 years learning about KISS and what CMP was trying to teach us back in 2004 about being efficient and doing things that make sense.
It’s been fun though and we’ve learned alot can’t say whether it was all worth it though…
KISS
DEF: to finally realize, that it’s just a surfboard nothing more and that the wave/beach is more important…
no, not lapping the inside cloth.
on the kevlar taped rails, the inner cloth sat within the border of the rail tape
as a means to equalize the surface; the bamboo veneer extended over the
tape edge.
Quote:
… ride quality is mostly dependent on the quality of waves anyway.
I’d rather ride an avg feeling board in great waves, than to ride a great feeling board in shitty waves.
How true. What I need to do is stop working on boards and start building a reef at my local beachie which seems allergic to sandbar formation these past few years… How long would it take if I drop one rock at a time?
Damn,it took bamboo hardwoods 2 weeks to get my veneer here.