Hi Woodsup,

I am in the same boat. Being a model airplane builder, I really like to do my own SUP. I have bought a plan from Sliver, but as time is a problem, I went with a cnc-cut fishbone from Tucker Surf Supply. I found two suppliers for Paulownia here in Germany, one of them being just around the corner. The fishbone is made of 3mm light-ply, the Skin will be 5mm Paulownia for the top and I consider 4mm for the bottom.

155l is a great size, I reckon that'll be 10' something. But it depends on what you are going to do with that board. Do you want to paddle on lakes and flat water? Then I would go for a longer board, as it will have more glide and track better. If wave-riding is part of your fun, then I would tend to the shorter size. I will be building a Stu SUP in 9'6" as I find my 10'6" Longboard quite a handful in head-high steep waves and want something handier :)

BR,

David

Hi David,

Great you're in the same boat. Our projects will be a blast. Looking forward to see pictures of your progress. The SUP we're gonna build will be more for the sea with the occasional wave. I live in Spain, on the coast. I've found a paulownia wood supplier here who actually has his main base in Germany but the wood is sourced from Spain. I would be more than happy to share his contact with you. About the skin, 5mm for the top seems excessive. Although, who'm I to judge with such little experience? ;)
Have you build one before? Did you use the 5mm top and 4 mm bottom? And what thickness of fiberglass did or are you going to use? I suppose you can play around with less thickness for the decks and a bit more for the fiberglass. I am considering one layer of 6oz for the bottom deck and two layers of 6oz for the top. Although I'm not sure if that is excessive and too much weight.

You don't say what the fibreglass is for. Strength or sealing ( or both). You also don't say what you problem to fibreglass is . Fibreglass is made directly from sand and when it degenerates it goes back to itself. It also doesn't float so won't gum up the oceans. If the problem is the matrix ( epoxy, polyester etc) , you said you are using the new bioresins anyway.
Carbon fibre actually makes a carbon sink. It isn't going to turn into CO2 anytime soon.
There is a fiber made from basalt. But believe it or not that fiber is biodegradable ( it turns into clay, instead of silica like fibreglass). , though it takes a while.
Most of the other fibers are polymer based and are not as biodegradable.
By the way all resin reinforcing fibres can be used ( and should be) for increasing the strength of concrete after use .
Wood is such a beautiful thing for any watercraft though.

This is an 11ft sup I made. Good allround shape.

tarquin1 said..
This is an 11ft sup I made. Good allround shape.

Looking slick! Is this the one you vacuum bagged on a foam blank? I'm curious how the finish is on the top deck. Do you need to wax the deck or is the cork exposed and therefore give grip? If so, how does it hold up while being bumped and scratched?

Yes that one is vac bagged onto a foam blank. Glass and carbon kevlar patches under the standing area.
If you get good quality cork it lasts. I just seal it with water based varnish. When it gets a bit old looking just give it a light sand and another coat. The grip is fine. Havn't surfed it though.

Ask the type of Paulownia and density. The age of the wood as well. All the European Paulownia I have found is a hybrid and quite young wood. Its getting better though. I suspect if you have access to milling and CNC machines you know more about wood than your average Joe!

Obviously the younger timber is not as good. It will have more knots and you cant get wider planks. The younger timber also has more plith.
In general the European Paulownia is a hybrid and more dense than the Asian Paulownia. For once you want something from China!
Yes the raw planks are cheap but by the time you count 20-30% waste in milling its not that much cheaper. Paulownia also has a high silica content and bluntens blades quickly. Your friend may not be too happy about that.
Timber that hasn't been dried properly warps a lot and very quick once cut into strips.

Andy

The wooden boards you have made are beautiful! Well done. The spider is very cool.
Cheers

Bob