View Full Version : Tuttle fin in Deep tuttle box?

24th July 2009, 04:44 AM
I have iSonic150 with deep tuttle box, can i also put i.e.
Tuttle 50cm fin in this board?

24th July 2009, 10:20 AM
Hi prpa,
Yes, absolutely!
The cool thing about std. Tuttle and Deep Tuttle fin boxes is that the side fit and base length (at the root of the fin) are identical.
The Deep Tuttle fin root (and fin box) are all the same dimensions as the std. Tuttle, just 18.00 mm (0.709") deeper.
So, just fit your std. Tuttle fin into the deep Tuttle fin box and use fins screws that are 18-20 mm longer.
Fitting is pretty easy (do a search on this forum for "Fitting Tuttle Fins".
If the fin base stands a little "proud" of the bottom of the board, a few strokes with a file on the high spots (use bar soap as a high spot indicator) and it will seat in perfectly.
If the fin root goes too far into the board, you can use clear packing tape to "shim" the front and rear tapers a bit to bring the fin up flush with the bottom of your board.
Again, the main reason for the development of the Deep Tuttle fin box was that for fins with a span (depth) of more than 60 cm there were some strength issues with the std. Tuttle box.
The Deep Tuttle box provides more support area to prevent shear forces from "prying" the fin box out of the board.
Hope this helps,

24th July 2009, 06:52 PM

25th July 2009, 06:01 AM
Hi Romas,
Did you ever get the 52 cm st. Tuttle base fin to fit correctly in your iSonic 145?
I'm wondering if your finbox had a "lump" of epoxy on the back taper to "set the
Unfortunately, the folks at Cobra sometimes do the "glob of black epoxy" on the back taper of the fin box to make a fin box that's out of spec. (the fin goes in too far) work better with the fin.
This results in a really small area of contact on the back of the fin and yes, the fin can be "stuffed" up into the fin box by pretty minor impacts.
Only way to fix this is to grind or file out the "lump/glob" and carefully use either mold release compound or wax paper to fill in the entire back edge of the fin box so the tapers engage correctly.
Hope this helps,

26th July 2009, 01:53 AM
Thanks Roger for Your replay.
I still after 2 years sail iSonic145 with great satisfaction.
I use only deep tuttle fins without any problems.
iSonic150 are wide board this allow get great presure to fin, especialy if rider are heavy man.

27th July 2009, 06:56 PM