Just finished this one. 4'6 x 19 and 32ltrs. 2.3kg. First board with concave deck and can't believe how hard time im having getting used to it. The stiffness/rigidity of the board doesnt help:O was getting thrown off the first many rides!!

Wanted to show you all the new boxes Ive come up with. Easy to install, 20% lighter than 10" chinooks, super rigid and big adjustment span. Oh and they are inexpensive:D Im 3 sessions in and they seem to hold up well

I feel like if it's bucking you like that on takeoff that's a result of too much flex, not too much stiffness.

The load of the foil bends the board, increasing the angle of attack of the foil, increasing the load on the board, increasing the bend, increasing the load.

I went through it on my last board. Full carbon,
double carbon stringer tied to boxes, solid divinycell blank.a monster.but only 2" thick. Stiffness is the square of thickness so even with all that.. Ended up fixing it with 12 oz of uni carbon on the deck connecting the front foot to the box area.

As for the aluminum tracks. I say the last 5 sessions max.

the carbon and aluminum will form a
circuit and electrolytic corrosion will decimate the aluminum. Carbon and aluminum hate eachother. If your foil is aluminum your a little better off but if it's a full carbon foil it's toast.

Also, there's going to be bond issues. With regular tracks, the plate is augmenting the bond because the layer of carbon over the top of the boxes is sandwiched in the connection. In this use your missing that layer over the top.

Also, aluminum is the last thing that carbon is going to bond with. It's just not porous enough, thermal extension will slowly tear the bond apart with every heat, cool cycle.

The board and craftsmanship look great tho. I just don't see the boxes holding out.

Regarding the flex I would add that my board I had trouble with had extreme deck scoop. Regardless of what else is going on less thickness at the mount = less stiffness. Even if the rest of the board is super rigid. I didn't believe it
myself till I added the Uni and it improved (but not eliminated) the bucking flex.

What's the thickness at the mount? Based on your volume 2" I bet. On mine I could stand on the nose and wrench the foil and really feel it compared to
my thicker board which has less reinforcement but is thicker and much stiffer.

Those MMA adhesives are very cool stuff,if anything is going to stick metal&fiber it's Methyl Metacrilate Adhesive.
Is it hard to work with?
Which brand/type did you use?.
I can get Crestabond M7-05, i think it is the one designed for something like this.
And the rails, what are the specs?.

Interested in how this works out,seems like a very innovative ,well planned and built board.