What feelings do people have on deck concave? I have a Sunova Pilot with concave described below and sometimes I feel like it would be great if it was more pronounced, especially with wider span foils to give you a feeling of moving towards an edge as you move your feet out.
I liked having a nice progressive concave on downhill skateboards, so can imagine similar feeling with the foil, but don’t really know where people are going with this.
We have a concave deck to get the rider as close to the foil as possible while maintaining the volume needed. It’s a soft concave without any drastic edges so it doesn’t trap water on the deck after takeoff. https://sunovasurfboards.com/en/foil/surf1/pilot
Benefits of a concave are maybe increased rigidity and reduced deck thickness?
I really like deck concave. The few times I have borrowed a board that has a flat deck I then realize how much I love the concave. I am sure there is a point when it becomes too much but haven’t found that yet.
I suppose the origin for a bunch of the shapers is in surfboards where a nice concave is physically impossible with the requirement for sharp bitey rails, that really isn’t as much of consideration with foils, save for the foam rebounds and tail touchdowns.
I haven’t looked at the geometry of a concave vs flat, but it definitely feels like it gives you more leverage on a skateboard, and it certainly gives your feet a reference for where in the board you are standing, both positives
I built my custom board with deep deck concave 2 cm .
Even for pronefoil and kitefoil pocket boards.
It give finaly the same feeling as your foot on a skateboard , ability to know where the foit is exactly and conpensate pressure.
For me it is a way to have a easier pop up with the hand grabbed on the rail caus it let you more space for your front foot to get placed
I think clearing the front foot is the biggest advantage of a CC deck, my first prone board was a converted surfboard with a heavily domed deck and I had lots of trouble tripping on my front foot at takeoff. When I made a board with CC deck the tripping issue went away.
My next prone board I might go CC deck at the front foot and flat at the back foot for more even foot pressure with a slightly offset stance
I tried a concave deck on a 5’8” x 25” sup. The concave was 3/8” deep in a 10” span. I thought it was great for winging but I didn’t like the extra sensitivity while going downwind, pumping or surfing so I sold it to a winger.
Good Q! Personally I like the sunken deck (flat-cave/tub) in front and progressive in way rear like a skate deck actually. The rational is that concave in front is too sensitive, foils take almost no pressure to rip into turns with the front foot, plus when pumping the feet can get a little crazy and flat isn’t that sensitive… Now the secret sauce is when you move your rear foot back into the concave for for real turns that you need allot of pressure to level the foil out…
Tried this out on numerous boards and a few friends. New foilers usually think they want concave to tackle where to put their feet, but imo it can be a determent. I’d suggest a center line bump with higher eva foam for confidence on foot placement.
Yes to your point that the curve generally increases rigidity, which is good. Noodles, no good.
For reference this is on 4’4-6" prone boards…
Since original post, my latest board is perfectly flat (4’4 gong). Somewhat surprisingly I haven’t really missed the concave at all, so perhaps I’m not at a level where it’s significant.
I do like the idea of a centre reference line.
On second thoughts for the skate reference - one usually has heel and toe on the rails due to the narrowness, where as with foil bord you’re moving them around way more.
The Amos Spitfire I’m riding has a flat deck and I prefer it. Went back to a concave briefly the other day for a test session and didn’t like it as much. The flat deck feels livelier to me. I reckon it’s a taste thing more than anything.
I agree That the foil is so loose that you don’t need much concave To lock in to turns. For me, the bigger factors are foot pain because I am standing up so much and consistent location of my foot placement. I find if there’s any concave in my standing area it causes a lot of foot pain. Flat deck is really a winner there. For back foot placement rail to rail I have a long arch made out of traction foam. This lets me get some for aft movement and really locks in my rear foot placement as well as helping with that foot pain by giving some arch support. For front foot placement and I just have a really small area of traction right where my foot goes. This makes it so my foot naturally stops on the road spot on pop-up and if I’m off a little bit I have that texture difference to give me some feedback on where I need to move it. For me this is really critical. On a new board where I have too much traction I’ll find myself in the front foot too far back on my pop-ups and I’ll even go in mid session and trim that traction back to get the perfect placement.
i have just switch from concave deck to flat deck and for me it feels way more natural. The flat and steady platform under both feet inspire me confidence when i am turning and pumping. The offset stance feels more natural too.
I think it is better to go with a flat deck and the lowest possible overall thickness than a concave deck with huge thickness near the rails.
Some boards, like Appletree if I recall correctly, have a recessed deck, where the standing area is flat(?) but you still get the yoga blocks for fitting in your foot.
I’m building a deep recessed deck into my DW board… pretty stoked. I think it makes sense, effectively the same paddling volume, but removes 1.5" of thickness, from 6" down to 4.5"
Volume of the recess is 12-15 litres, mostly an experiment to see how much of an impact it has.
It is modelled on a rescue race board dimensions which seem not to hold water, especially when prone, which is the idea. I think the recess volume when prone will be reduced 50-70%
We tested a bunch of different options and ended up settling on a subtle concave. Our boards are all 22" wide or under though, so not enough space for a recessed deck without interfering with toes and heel of an offset stance. If we did a wider beginner wing board I’d definitely consider a recessed deck. Haven’t tried one myslef, but like Armie’s concept of the through handle for drainage.
Love a subtle concave but my size 15s can’t deal with the Armstrong or bathtub style with the sharp transition out at the rail. Subtle concave is the next best thing to footstraps.
