I want to thank my wife Kristen for all the pictures, video and most importanly all the love and support she gives me in this and all my projects! Shot out to her folks Dick and Sue for all the time the have given behind the boat and all the support they give both of us in general! I hope this brings a smile to a face or two!

Cheers!
David

Very nice, thanks for sharing!

Very cool

Please give us the boards specs

Is that second board project or a continuation of the first? The color looks the same. Its encouraging to me to see larger sailors foiling! With the foil, board, rig and myself I have 252 lbs to lift.

Nice work David

The board in the video is the board I launched a year ago and I have got well over a hundred sessions on it at this point. The paint has worn of here and there, no surprise i used single part. It could look like new with an hour spent painting but I won't. There is one repair on the transom corner, and I reinforced the other side for good measure. I did not think to put innegra back there and the boom head hit it in a failed heli tack. The innegra patches at the nose have survived many massive catapaults! There are shallow indents at the heels and roof racks but the skin is still stuck, no surprise here either it is not cored. Over all it has exceeded my expectations! To my eye the outline shape and volume distribution looks a lot like a scaled up version the new wizard 130! When I get my next board up and running I may recycle this blank and take some width an length out of it but not much.

www.seabreeze.com.au/forums/Windsurfing/Foiling/Big-guy-s-one-board-windfoil-quiver?page=1

Water Craft Design Custom Windfoil Board
Length: 6'6"/ 198 cm
Width: 34"/ 86 cm
Thickness: 4" / 10 cm
Volume: 177 liters
Construction: Carbon and Innegra over eps blank
Weight: 21.5 pounds / 9.75 kg

Here is my progress on the hollow board with bevels. Kids, do not try this at home! It is a very slow and costly process! I also have gotten a bit dstracted by a boat design/build project. When the shredshled was released a while ago I found some new energy for this project.
The yellow thing is the plug not the finished board. I still need to lay up a bottom mold before the actual board begins. The bottom two pics are the plug. Next one up shows a deck mold half done. Next one up is the two deck molds on the plug. Top pic is the two deck molds with the plug in background. I am still stoked on this idea if for no other reason than how much I have already learned!

Select to expand quote

utcminusfour said..
Here is my progress on the hollow board with bevels. Kids, do not try this at home! It is a very slow and costly process! I also have gotten a bit dstracted by a boat design/build project. When the shredshled was released a while ago I found some new energy for this project.
The yellow thing is the plug not the finished board. I still need to lay up a bottom mold before the actual board begins. The bottom two pics are the plug. Next one up shows a deck mold half done. Next one up is the two deck molds on the plug. Top pic is the two deck molds with the plug in background. I am still stoked on this idea if for no other reason than how much I have already learned!

Hollow? Whats the cross-section look like

Glass -> divinycell -> air? I can't see how that would work, must be something else.....

Are not Patrick boards also hollow? Maybe only his formula boards?

In the 90s John Doyle produced custom hollow slalom boards. The structure was skin on honeycomb, then hollow under the honeycomb. He used the honeycomb for various stringers and reinforcements, but most of the volume was hollow. The honeycomb was about 1 inch thick and really light. You still see his signature blue boards around in the gorge.

www.doylesports.com/index.php/company

Great builds. Whats your thought process now going to the bevels? Did you find the old board a bit iffy on touchdowns with the hard rails? Also interested that you have decided to take the bevels all the way to the tail.

Maybe easier to build than a board with cutouts?

Thanks everyone for your interest!

Thedoor, see the diagram below. In the top picture above, look on the shelf and you will see two cross section test samples of hollow construction. The core on those test samples is way to thin. I will likely use 1/2" to 3/4" core, it depends on what I can scrounge up from local composite shops. I have a lead on some nomex honeycomb locally!

Segler, yeah Patrick has a line of hollow boards called air inside. Thanks for the link to Doyle. This is not a new idea just a way to get the weight out of high volume shapes. It is too exspensive to be profitable for most boards and builders. The high volume pro racing windfoil boards are a good use of this technique. I am doing it because I have always wanted to.

Swoosh, as you have learned by now you never want to touch down, ever, period the end. There is not much a boards shape is going to do that will overcome the decelerations involved. For me the interest in bevels comes from looking at the boards on the wing and surf foiling side of things. Put simply a flat bottom doesn't want to release. I have a SUP with a handle on deck and it is impossible to pick it straight of the water, I have to tilt it over to brake the surface tension. Windfoiling is different than windsurfing, the boards should be different. I prefer to ride with more wing and less sail. With a high lift wing and pumping I am free and flying before planning speeds. Thats why I want to explore a shape that has less drag below take off speeds. This shape has 15% less wetted surface than my last shape and the tail kick with a narrower tail approximates the shape of a sailboat hull and will tow less of a wake behind it. Moving the foil forwards allows for a tapered tail because the riders weight stays forward. I know this shape will fly sooner and easier but it may be worse in touch downs because of all the curves. I am deliberately building to very different shapes to help wade through all the conflicting marketing information.

Select to expand quote

utcminusfour said..
Thanks everyone for your interest!

Thedoor, see the diagram below. In the top picture above, look on the shelf and you will see two cross section test samples of hollow construction. The core on those test samples is way to thin. I will likely use 1/2" to 3/4" core, it depends on what I can scrounge up from local composite shops. I have a lead on some nomex honeycomb locally!

Segler, yeah Patrick has a line of hollow boards called air inside. Thanks for the link to Doyle. This is not a new idea just a way to get the weight out of high volume shapes. It is too exspensive to be profitable for most boards and builders. The high volume pro racing windfoil boards are a good use of this technique. I am doing it because I have always wanted to.

Swoosh, as you have learned by now you never want to touch down, ever, period the end. There is not much a boards shape is going to do that will overcome the decelerations involved. For me the interest in bevels comes from looking at the boards on the wing and surf foiling side of things. Put simply a flat bottom doesn't want to release. I have a SUP with a handle on deck and it is impossible to pick it straight of the water, I have to tilt it over to brake the surface tension. Windfoiling is different than windsurfing, the boards should be different. I prefer to ride with more wing and less sail. With a high lift wing and pumping I am free and flying before planning speeds. Thats why I want to explore a shape that has less drag below take off speeds. This shape has 15% less wetted surface than my last shape and the tail kick with a narrower tail approximates the shape of a sailboat hull and will tow less of a wake behind it. Moving the foil forwards allows for a tapered tail because the riders weight stays forward. I know this shape will fly sooner and easier but it may be worse in touch downs because of all the curves. I am deliberately building to very different shapes to help wade through all the conflicting marketing information.

I see, very cool. But how do you get the divinycell to conform to the mold?

In this case all the surfaces are pretty flat and I will just do mitered corners, relief cuts and use a vacuum bag. It can be heated and thermoformed to fit compound curves. You can see in one of the pics of the deck molds above I used double contour cut foam, its essentially squares of foam held together with a light scrim fabric. This stuff is easy to get around the curves and often it can be shipped rolled in a tube so it saves on shipping. No free lunch though, the gaps fill with resin so its heavy but it made sense for the mold.

Love the hollow board project!
It's something that has been on my mind for a while.
In another topic, some members are discussing the concemt: www.seabreeze.com.au/forums/Windsurfing/General/building-eco-boards?page=6 (check from Duzzi's message 24/11/2020 11:30)

Great job. Can't wait to see your finished product. Will your hollow board have a drain plug? Is humidity/condensation a factor??