Hello all. Wondering if anyone had any advice for this perhaps unusual question. I ride a sup on the ocean, on the waves, but have lately been cruising up and down river systems on the sup due to an injury.

I attached a makeshift sail to it a few months back and it got some great movement forward with the wind on my back on two sections of the river but when the wind was blowing at a 90 degree angle to my board instead of behind the board, it wouldn't propel forward. I only have fins in the back. Nothing in the middle.


if I install my own fin box in the middle of the board somewhere underneath where the handle but not directly under, and put in a fin say the size of a large rear fin for a mal, would this provide enough whatever is needed to make the board go forward in the wind is blowing at a 90 degree angle to the board?

My injury is nearly healed and I want to now combine the sailing aspects of the river with the surfing. plan is sail to the surf spots that are hadd to get to, very slow speed. Then when there take the fin off in the middle of the board and stow it at the front of the board somewhere, I'm planning on getting one of those mini kite things people use for downwinding foiling, and then stow that when there also.

thanks in advance

This sup has place to mount a universal and 5 fins so it goes upwind pretty good. Mounting a finbox is quite complicated. They do make stick on fins or ones with straps.

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Hydrosurf said..
This sup has place to mount a universal and 5 fins so it goes upwind pretty good. Mounting a finbox is quite complicated. They do make stick on fins or ones with straps.

What do you mean it has a plce to mount a universal?
Boards nearly dead so it's not going to be the end of the world if I ruin it attempting my first fin box placement.

those strap on ones a pretty cumbersome no?

It has a threaded insert to screw the universal into, not your typical mast track.

Sups will go across the wind ok wit just the rear fin. Obviously, yes, better with a centre fin as you correctly identify.
but - this totally is a first time technique thing or a problem with the makeshift sail (what is it?) if you can't even sail at 90deg. I've taught kids on a SUP and they sail on a reach after a couple of hours.
maybe a better rig and practice first?

Don't need a center fin the go upwind. Both my WindSUPs have gone upwind fine on just the rears.

However if you want to explore the river by sail I'd look at an old windsurf board with a centerboard. They can be found cheap and will do what you ask much better.

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Mark _australia said..
Sups will go across the wind ok wit just the rear fin. Obviously, yes, better with a centre fin as you correctly identify.
but - this totally is a first time technique thing or a problem with the makeshift sail (what is it?) if you can't even sail at 90deg. I've taught kids on a SUP and they sail on a reach after a couple of hours.
maybe a better rig and practice first?

Winds were very very light on the stretch I was struggling on. The sail was a bit of pvp pipe duct taped to my sup paddle and only 1m wide and then had some old canvas I rolled and duct taped to the PvP pipe and I stood on the canvass on the board to keep it in place.

I was hoping to go at walking pace if possible