ANY OF YOU GUYS HAVE ANY PICS OF THIS CORK WORXS?
WW, when using GG you gotta use very little…a very thin film is plenty especially if youve got some pressure on the parts. GG is also good when trying to fill loose gaps is less than perfect mating parts. A dimpled/textured surface increases mechanical bonding a great deal.
Use a hard plastic glassing squeegee to spread the GG. One 3/16" or so bead for a whole rail line and spread & spread & spread & spread until its thin & worked into the EPS. Balsa doesn’t need any water misting, but if you’re joining more foam (EPS, d-cell, etc) mist the other side of the joint with water. Lightly. Clamp or tape well. Blue tape is enough to stop the glue expanding out, but it can stick as well so leave your pieces proud enough to stand some sanding to get the blue away.
Hi cj, did you do both sides at once? And did you tape the layers and the offcuts or did you bag them?
llilibel
This was my first attempt so I went real slow. I taped and clamped one layer of one side each time. I tried a few different methods and glues. Clamping the offcuts with the long clamps and a few ratchet tie downs and a 1x4 piece of wood on the outside of each offcut seemed to work the best. For the balsa to balsa gluing, the wood glue worked well and is pretty economical. I like the foaming glue for the balsa to eps.
After bagging the skins on and bagging some fins, I am becoming quite fond of the process so I may try the rails next time.
christian
Christian, did you put the skins on with foaming PU? Is there any glass or epoxy under them, or just on the outside?
Ben
This is what we do it may not be the best
only Bert really knows…
1st 1/8" or 3/16" layer (wood) which acts as the perimeter goes on with foaming PU glue elmers or GG.
Roo is even better since its safer and is used for stringers
CMP switched to Roo from GG awhile back to build his EPS blanks.
The subsequent layers are added on one strip at a time using CA super glue you just hold it in place with your hand and some green tape for a minute or two.
For the straights where the curve is less intense we use 1/2" to 1/4" thick balsa to speed things up. we use a heat gun to prebend and smaller cuts with scarfs for the curves.
For the compounds we switch to 1/16" or 1/8" mixed with 1/8" cork as a filler again with thick CA super glue.
Like Jarrod said about the deck and bottom, strips are more efficient as long sheets will have release gaps unless you do a heck of a job during the vacuum pull. It can be done but it’s way harder. I got lazy and bought these 4’x8’ sheets of cherry and maple veneer from Paul J’s source and the result is pretty and easy to cut but you really have to press down the sheet as your vacuum pulls. Obviously bottoms are easier. Foaming glue is better for this but real slow curing regular epoxy (I use system-three for this) works as well too.
The bamboo sheets are a cheater for us and works well cause it’s only 1mm thick but at this point I’d only use it as a deck strip down the middle because it’s so strong to prevent pressures and balsa on the bottom and sides because it’s easier to shape and blend. With perimeter rails though there’s less belnding required of the deck and bottom skins and more rail shaping.
Go with Benny and go thick and chunky with the rail then shape.
I put 1.5" thick core cell rails on my two bamboo boards after shaping the rail drop and it was a mistake cause it pulled the rail too thin. Thick chunky rails will allow you to concave the deck.
Hope this helps
Benny,
I pretty much followed your checklist on the skins. RR epoxy/4oz glass under 1/16 balsa and epoxy/4oz on top then in the bag. The top turned out great after making a few mistakes with the bottom. I tacked the fins on yesterday and should have it ready to go this weekend.
Do you use the slow hardener when you do your longboards? On the fish I felt like I had just enough time to get it into the bag with the fast hardener.
If you can bend the wood, I’d go with thicker wood on the rails. I used a heat gun to bend 1/4" and 1/8" balsa. I have been making eggs, so there’s a lot of curve in the nose and tail. With a more traditional shape it should be easier to bend, and it’s a lot faster using the thick wood. I would also make it at least 1/2" to 3/4" thick and shape the top after gluing the rails on.
I shaped the top of my last board and laminated the top skin on before adding all the rail bands. I didn’t like the end result. I think you will have more control over the shape if you do it after adding the whole rail. We also did a board where I cut the rails off after laminating the top and bottom, and glued on wood rails. I had better control of the rail contour, but I’m not sure if that adds any strength because the top and bottom skins don’t overlap the rail at all. We use 5 min epoxy for the first layer, then just use super glue for the rest. It’s a lot easier to sand through super glue than epoxy.
If we ever get as good as CMP, we’d just do a top and bottom skin and lap them around the rail like he does. That saves a lot of time, but it isn’t as easy to get the wood to lap the rails just right.
I also think balsa makes a very hard skin on the board. All the other woods we use, with the exception of the woven bamboo, are not as hard, even with a layer of glass under the wood.
Christian, I just use fast. The more you do, the more natural your movements become, and the faster & smoother everything goes. And my shop is so small, I don’t waste any time moving around 
You’d be amazed…
Shark Co, I agree with you about strength of overlapped skins vs. skins first, rails second. But I like the look of rails second, so I’ve been experimenting with running strips of carbon fiber under the perimeter of the deck skin to firm up the hand/foot areas over foam and next to the rail. Seems to be working quite well…