Board specs: 8’6 x 29 x 4 5/8" 1.5 lb Marko EPS core with a 3/16" bass stringer. I’d like to bag a bamboo veneer on the deck only and want to keep the board as light and dent-resistant as possible. I’m 6’3 and 210 lbs.
I’m being told to go with one layer bamboo and one 4 oz layer on the deck and two 4 oz layers on the bottom. Maybe wrap the rails with carbon to bulletproof them. I have zero experience with vac bagging or using veneers and to me, the deck schedule sounds weak.
I’ve poked around here and online a bit and am wondering if I should add a 4 oz layer under the bamboo as well for a better bond and strength? Or maybe go with bamboo directly on core and a 6 oz. layer on top?
Since you haven’t started yet, dump the bamboo and get some NL-20 corecork(2mm) and wrap the whole board with it. Vac bag the bottom with 4oz cloth and cork. then do the top the same but wrap the rails. Glass with 4 oz deck and bottom No need to reinforce fin boxes or carrying handle. If you haven’t shaped your blank, bring it back and trade it for a 1lb blank and just reinforce the fin boxes with some 5 lib high density foam.
You also state you never vac bagged before. Best to find someone who has to help. The info above has probably hundreds of nuances and steps to do it correctly.
One good thing about bamboo or cork under the glass is that it will use less resin. All the resin that would seep into the deck of your board gets stopped at the veneer. Your board will be lighter for that.
Actually, Bamboo is so 30 years ago. The problem you may have with it and 1 pound foam is excessive denting and heel pressure dings on an SUP. Def use 1 pound, but what is good about cork is that it separates the structural glass with a filler and makes it a better composite. If you go with bamboo, make a true composite sandwich by using a spacer under the bamboo so that you have foam/glass/divenylcel (for instance)/bamboo/glass.
Thanks all. The board is being glassed by a highly reputable factory here in Santa Cruz. We’ve decided on a 1.5 lb core/bamboo/6 oz on the deck. 4/4 bottom with 2x2 plain weave carbon fiber on the rails.
IMO bamboo veneer is beautiful. You don’t mention the thickness of your veneer. Like the above post states, I too don’t see less heel denting so I am skeptical on its benefit in added strength or durability. I personally think the veneer I have seen is so thin, the potential advantage of any added strength or durability is lost. I would double up on the veneer and put a piece of 2 oz cloth between the veneers. On an sup your size the added 6 ounces will not be noticed. Also, why not veneer your bottom with a single layer also? If there is a plastic engineer or a windsurfer expert at this reputable santa cruz factory, they may have some valuable opinions concerning this.
The other thing I don’t like about bamboo is that you can’t easily wrap a rail with it. Carbon fiber tape or cloth for that matter is at least 20-40 times more expensive than NL-20 cork 2 mm material. The most abused part of your sup will be your rails. You didn’t mention the weight of your carbon cloth you are using but you need at least 5 oz weight. Your added CF rail is mostly for protection unlike getting a deck and rail wrap together with cork or balsa veneer where not only is it protected as good or better and cheaper than CF but the structural durability of the whole board is way better than your current plan. You could even use 1 lb foam and come away with a lighter, stronger product.
If I sold a board you are having built it would be by customer request only with no guarantee.
Please let us know how it holds up over the next few months. I hope you can be telling me “I told you so”
Oh yeah, don’t forget to gortex vent it also. Don’t go cheap and use a screw in and out type, spend 5 more dollars and do it right.
I’ve had very good results using bamboo veneers, really strong. I use the 1/40" thick bamboo with a 6oz over the veneer for the bottom and the top gets a 4oz under the veneer and a 6oz over. I put 3k carbon tow on the rails to act as my stringer since I don’t put stringers the blanks. I have also had very good results with surfboards using bamboo and 4oz layup no 6oz. The decks on the surfboards are very hard. Bagging is easy. You just need to get all your ducks in a row before you start. Prepare your bag first make sure the blank will fit in the bag. Pre cut your bleeder and bagging film for both sides. Then cut your veneer to fit flip it over and and lightly dust it with 3M 77 then roll out your cloth, trim the cloth to the edge of the veneer. Now your ready for resin, pour the resin in a large paper plate use a small 6" or 4" tight nap roller to apply the resin. If your really quick you can do both sides of the board at one time. tape the veneer down and put on the bagging film (release film) and bleeder stick it in the bag and pull your vac. Leave the excess resin in the plate once the resin in the plate is hard it’s safe to remove the board from the bag.
I wouldn’t call it leading the pack because a shaper in FL name drewtang has it wired. Being one of 7 people on Oahu who can vacuum bag helps though.
The next new thing in sup’s will be cork. It is not just any cork but corecork NL-20. I like the 2mm the best. To answer Harry’s question I have a couple rolls and you guys are welcome to use mine if you need.
assuming the bottom is a simple 4/4 layup – this applies to the deck only:
what would the difference in weight be between a 6 oz layer over bamboo veneer (let’s assume 1/40" thick) applied to foam core and a 4 oz layer over bamboo with another 4 oz layer under bamboo applied to core (sandwich style)?
from what i’ve learned the sandwich will greatly improve deck strength but at what cost to the weight? would one even notice?
I still have time to change my deck schedule if needed.
For 1.5 to 2# eps I like 2oz under the bamboo with 4oz warplite over it on the deck,same for the bottom.I’ve found bamboo to not be a good skin over 1# eps(the foam colapses in the traffic area),you need a thicker composite like 1/8" balsa or 1/8 divinycel.Maybe the cork would be good,I haven’t tried it though and may never get around to it due to it’s cosmetics.
How would you get it around the rails? I’ve tried vacuum bagging cork over the deck and the bag sucks the cork away from the apex of the rail. I would think you’d need a mold to get it to drape right.
Hmm, apex? Midpoint of rail between deck and bottom? If so it shouldn’t be problem, unless the cork is that stiff. I’m also assuming you’re letting the bag material bunch up at the rail as it sucks down on the deck. If thats not the case then I aplologize for overstating the obvious.
If you are using a full bag setup then you pull the excess bag all the way onto the bottom when bagging the deck. Hard to just say without pictures, but I’ll try to explain.
So lets say it’s the deck your bagging. You’ve centered your material to bag onto your blank, placed the board into the bag, sealed the ends and started your pump. It usually takes a few minutes for the air to be sucked out of the bag. As it starts to pull down you gather all the excess bag material onto the bottom of the blank. I’ll usually turn up my pump to max to quicken the process and right before it starts to compress the material I’ll turn the pump off. To make it easy you can flip the board over, if its deck up, and pull all the bag material towards the center. It doesn’t need to be perfect only tight at the rails. You can turn your pump on to adjust, turn it off, turn it on, etc. Then as you get it close turn the pump on and set it as low (less vacuum) as it will go. This will give you time to tighten the bag material over the rail material without it having creases or folds.
It just needs to be smooth over the edge of the material your bagging. If there is excess bag it can suck under the cork or bamboo.
Thanks DMP! I think you just saved me years of headaches vacuum bagging. I use one of those thicker reusable carpenter’s bags with the sealing rods at the end. I have a feeling bunching it up will work fine. Always nice when there’s a simple solution.
Your welcome. Just remember there is really no rush. Unless you’ve done something foolish with the resin, once its spread thin on the back of the veneer it will take much longer to kick than a regular lamination. So take your time and pull that bag material tight over the deck and rails. The less bag material you have on the deck the less chance of creases forming which can trap resin in. Which means more prep time before the next step. Also try not to cut your bag material close to the nose or the tail. Extra bag material at the ends make it easier to pull the excess onto the bottom.
Go to http://www.acpsales.com/ and order yourself some proper bags. It is cheap and you can get as much or as little as you need. The bag material is pliable and if used properly can be used over and over.
I just finished a 9’2" sup with bamboo on the deck and will try to post some pictures.
This one 9’2" x 28 1/4" x 3 1/2". Shop board so 6 s under 4 warp over on the deck. 7.5 E with a 4 warp fin patch on the bottom. A few extra pounds more with the 6 under but still lighter than a standard glass job.
This one was a hair puller. So many problems, stains on the foam, boned the veneer by not ordering a long enough piece (paint cover up on the tail from the scabbed piece, not good), fish eyes, sand throughs, arghhh! Had to sand and hot coat the deck 3 times. Ended up doing a final hotcoat, super thin with no F on the deck and let it alone. Just sanded and blended the edge on the rail.
What we were taught is to tape the veneer down in strategic spots, then wrap the board with a thin plastic sheeting pulling the sheeting real tight and tape it down. This holds the veneer down while you get the board into the bag. You need to make sure you keep that sheeting tight because it can get between the board and veneer and make things worse. If you do this part right, you won’t have to worry much.
Otherwise keep smoothing the veneer out and keep pulling the bag out and away from the board as the vacuum sucks down.
Kirk or BB30, does the resin soak into the cork? Any issues with weight from that? Do you need to seal it?
I’m guessing the the real strength is not so much in the material itself, but the thickness, being more than 3 times the thickness of 1/40 inch bamboo veneer. And as BB30 says you can go with a lighter core and still maintain a fairly tough deck.
Wow, nice board. I think you have the “first to do it” on SUP boards claim on the West coast now. My prediction of the next new fad in board construction has not taken off yet though. Full wrap or deck only?
