Was thinking of enabling a freeride board for youth learners. Like, adding the US box in the middle, so it can be removed as they progress.
Would it work?
What would be the cost of such an exercise?
Any better ideas ?
Better to add a PB or tuttle to get a bigger fin more easily. Really hard to find cheap US in under 24 as they all go to secondhand SUP's and over that size was bloody hard to find after they fell out of favour 20yrs ago (plus?)
$50 to $75 to do it yourself.
But find a busted freeride board, cut the box out, getting cheaper!
Several boards a few years back had these including my beloved first gen Starboard Start. The Start used a tuttle box, fwiw. I think I've seen a more recent Go have something similar. Starboard used to make a Drake shallow water fin which was a fairly low aspect tuttle box fin that also worked well for a center fin.
The Start also came with a blank to fill the fin box so you could use it conventionally. On the deck, the recess to access the screws also served as a carry handle - it was one big cut out instead of the common chimneys you see on many tuttle boards.
There are also stick on center fins made for wingers to train on for their first excursions if you think that will suffice. A proper fin, though, will provide better upwind performance.
In WA 10inch and 8 inch FB
www.surfsailaustralia.com.au/product/chinook-fin-box-10-inch#surf-sail-clothing-hardware
Select to expand quote
He wants them to progress on the freeride board later I'd hate to think how this would feel (big lump)
Could add a box for same price
Thanks guys.
She is only 6 years, and already has an 80L wave board she's paddling around.
But to learn windsurfing,I was thinking of converting a 115L board to have a centre board, and after progressing, she could use her wave board, and I would donate this board to one of the junior schools.
The US box was on my mind, because it only requires a hole from the bottom.
A PB / Tuttle requires an additional hole on the top.
If you just want a US box put in and its for a kid I'll it for u for nothing mate
That's very nice of you to offer, but I would not expect it for free. 
Not to mention we are 500 - 600 km apart 
Select to expand quoteObelix said..
Thanks guys.
She is only 6 years, and already has an 80L wave board she's paddling around.
But to learn windsurfing,I was thinking of converting a 115L board to have a centre board, and after progressing, she could use her wave board, and I would donate this board to one of the junior schools.
The US box was on my mind, because it only requires a hole from the bottom.
A PB / Tuttle requires an additional hole on the top.
Sounds like a good plan. keep in mind that little kids with little sails need little rear fins (freestyle size) to go upwind
Center boar added. The bottom re-sanded and repainted. Great job, thanks a lot Mark. 
The board is looking great.
Select to expand quotethedoor said..
Sounds like a good plan. keep in mind that little kids with little sails need little rear fins (freestyle size) to go upwind
And to tack.
Yes, a small rear fin...
The smallest Powerbox I have - a brand new Select Lightning Speed 28cm.
I had some smaller, but "I didn't need them" , and they weren't in a good shape so they ended up in a bin
The center fin (US Box) I only have because my wife thought it looks nice, and "she would use it in the garden".
