Concave?

General Discussion
1

I want to put a concave into my next kiteboard through my vacuum stages. What should I use to form the concave?

I’ve heard of people using 1mm thick plexi but I don’t understand what they’re doing, what I was really interested in is what Bertburger was using, the contour mats that is, did he ever explain what they’re made out of or how to make one?

2

Bump.

Somebody’s gotta know something on this…

3

hi,

i believe bert said his matt is an impression taken from another board.

probably a bit overkill for a kite board.

try this:

use a rocker table that has 3 stringers.

then add the desired amount of concave to the middle stringer,

by adding a wood strip the same thickness as the concave.

secure a suitable molding surface to the top of the stringers.

(that’s the plexi sheet, or formica, or aluminum, fiberboard etc)

i stole this pic from an old post by rainer

-bill

4

I was just wondering what the mat was made out of… I know he got it from an impression of his last board, but what’s it made out of?

It’s been killing me every since I saw it back in january or so! lol.

Thanks.

5

guess it’s fiberglass.

Flavio

6

i’m sure he’ll tell you.

but i’d guess that its some type of low-med durometer

rubber molding compound.

i.e. polyurethane or silicone.

mold release the board.

spread on the goop.

clamp to a smooth surface to use as a datum

for rocker line.

yes/no?

7

^Even if that’s not it, my bet is on that it’d work.

This first one I’m going to use the table with the middle piece of wood adding 5mm up, to put 5mm concave

But I’m going to rip the bottom off of it if it rides really well.

Thanks for all the help!