View Full Version : Isonic 121 2010 Fin Bolt length question

28th February 2010, 02:53 PM
Hi all,

I have a question regarding fin bolt length for the Isonic 121 (2010).

In the fin bolt chart the lengths specified are:

Can anyone confirm whether these are the lengths for a Tuttle fin?
What are the lengths for Deep Tuttle (M6x60+65?).

Best regards,


2nd March 2010, 08:06 PM
a deep tuttle is app. 20mm longer than a normal tuttle.
Depends were the nuts (inserts) are positioned. ->
So calculate with 15-20mm shorter screws for deep tuttle

7th March 2010, 02:08 AM
Hi Pfaffi,

Thanks for your feedback.

I cut some bolts to size, ended up with 65mm and 60mm length bolts for my deeptuttle fins.

I do wonder why my 121 was supplied with tuttle bolts only (70 and 80mm). It would make sense to supply deeptuttle bolts too, the 121 after all has a dt finbox. And add the deeptuttle sizes to the fin bolt chart?

Gr. Julian

7th March 2010, 03:04 AM
They provide the longer screws beacuse they used to ship all boards with Regular Tuttle box. This year they did not ship boards with Fins. Drake Fins who is part of the Starboard companies used to supply all the fins for Starboard and they only made deep tuttle fins fr formula.
You can always cut the screw to the correct lenght or buy some online or in the local hardwear store