I am starting a new board and just got some Corecork NL 20 that I want to use as an alternative to Airex. I am also planning to leave is exposed on the deck, the same way LOST does it on their C3 technology. Plan is to sandwich 4Oz FG-2mm NL20- 4Oz FG for the bottom and 4Oz FG- 6Oz Carbon-2mm NL20 on the deck. Any advice? I was told the NL20 is quite easy to overlap the rails but I am not too sure if there is a particular technique to get a clean junction?

Corecork is cool stuff. Vacuum bagging is the easiest and best way to apply it IMO. I've done a few boards with the NL20. Although it might seem like you'll have these thick overlaps, just have faith and you'll find that the cork sands and blends easily from one layer to the other and blends together nicely. It's actually quite easy and forgiving to work with. I personally have found it a little too slick and rough without a pad. But that's just my personal finding.

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Reprobate said..
Corecork is cool stuff. Vacuum bagging is the easiest and best way to apply it IMO. I've done a few boards with the NL20. Although it might seem like you'll have these thick overlaps, just have faith and you'll find that the cork sands and blends easily from one layer to the other and blends together nicely. It's actually quite easy and forgiving to work with. I personally have found it a little too slick and rough without a pad. But that's just my personal finding.

So you would recommend to cover the deck with an extra layer of FG and stick a normal pad instead?

Also, do you have a particular technique for wrapping the rails? I am not too sure how to wrap the tail and nose without the cork rippling?

Let's just say you're going to apply the bottom first. You'll cut enough cork to wrap around your rails. Make your relief cuts at the ends just like you would with glass. Put your epoxy on the cork and put it in place. I take tape and wrap the cork down around the rails every few inches. At the ends you might have what seems like big overlapping globs, but fear not, all will work out. Just tape down the laps. Then I bag it all and pull the vacuum. When your blank comes out (remember you already have a layer of glass over the foam) you'll take a sanding block and feather the edges of the cork back down to the foam. At your globs just sand judiciously until it's all seamless. Really surprisingly easy. When you're ready to apply the top layer you'll cut enough cork to wrap, say just down to the mid to bottom rail. Take your steps again, epoxy, tape, bag (if you're doing so) and go. When it all comes out you'll go back at it with the sanding block feathering the cork edge back down to the first layer of cork.

www.swaylocks.com/forums/future-getting-under-my-skin

read this thread. And I'd suggest searching Corecork on Swaylocks. Anything posted by bb30 is gold. Guy is a VERY talented board builder and has quite a bit about cork. Where I got my info.

i started without a pad but later went to one. And yeah, another layer of glass and then pad. You should try it first without and see for yourself. For me it started out ok but got too slick over time

Select to expand quote

Reprobate said..
Let's just say you're going to apply the bottom first. You'll cut enough cork to wrap around your rails. Make your relief cuts at the ends just like you would with glass. Put your epoxy on the cork and put it in place. I take tape and wrap the cork down around the rails every few inches. At the ends you might have what seems like big overlapping globs, but fear not, all will work out. Just tape down the laps. Then I bag it all and pull the vacuum. When your blank comes out (remember you already have a layer of glass over the foam) you'll take a sanding block and feather the edges of the cork back down to the foam. At your globs just sand judiciously until it's all seamless. Really surprisingly easy. When you're ready to apply the top layer you'll cut enough cork to wrap, say just down to the mid to bottom rail. Take your steps again, epoxy, tape, bag (if you're doing so) and go. When it all comes out you'll go back at it with the sanding block feathering the cork edge back down to the first layer of cork.

www.swaylocks.com/forums/future-getting-under-my-skin

read this thread. And I'd suggest searching Corecork on Swaylocks. Anything posted by bb30 is gold. Guy is a VERY talented board builder and has quite a bit about cork. Where I got my info.

i started without a pad but later went to one. And yeah, another layer of glass and then pad. You should try it first without and see for yourself. For me it started out ok but got too slick over time

Wow, that's a lot of useful informations! Thanks a lot, it makes a lot of sense.

Just a last question, I am not sure how porous the corecork is prior lamination so I was wondering whether I need the usual peel ply over the cork before bagging it or not?

Cheers.

I would use peel ply. I just use the economy stuff, but I agree with what I've read. You're spending too much time and money not to go the little extra expense for peel ply. And it gives a nice fairly uniform finish. The cork is porous enough that when you pull your vacuum the excess epoxy will fill all the voids and help to make a very durable finish.

I forgot to add that if you have if you have an area where sanded too much or broke/chipped some cork off it's easy just to cut a filler piece and place it over your boo-boo with some epoxy and tape and feather it back in once it dries.

in the bottom photo you can see where one edge feathers back to the other.

good luck!