anti stuff fins

scottyboy · 13-06-2005, 09:33 PM

Does anyone have any experience with anti stuff fins? how do they work and are they any good??

JamesM · 13-06-2005, 09:43 PM

Is that whats on the front of that yellow P21 in the Ramsgate photos?

scottyboy · 13-06-2005, 09:45 PM

yeap!

Gav · 13-06-2005, 09:46 PM

Quote:

Originally posted by Johnny Boat Dude
Is that whats on the front of that yellow P21 in the Ramsgate photos?

its a moulding that Ian had made to make the boat longer to conform with regs for racing, summat like that anyhow!

Gav · 13-06-2005, 10:15 PM

Quote:

Originally posted by scottyboy
yeap!

i stand corrected!

Jon Fuller · 13-06-2005, 10:21 PM

I think you're both right, although they're more to assist recovery than to stop it stuffing, as they can't do anything till you've already stuffed it!!

Matt · 13-06-2005, 10:38 PM

I'm not sure. UIM 2005 elegibility is 6.2M or about 20' 4", so you'd expect a P21 to be OK. And I don't honestly think Ian needs them for anti stuffing (have you seen him drive!). I'll ask next time I see him.

Gav · 13-06-2005, 10:46 PM

Quote:

Originally posted by Matt
I'm not sure. UIM 2005 elegibility is 6.2M or about 20' 4", so you'd expect a P21 to be OK. And I don't honestly think Ian needs them for anti stuffing (have you seen him drive!). I'll ask next time I see him.

Ian asked me to quote for a "Bow Extension" some time ago

Jon Fuller · 13-06-2005, 10:48 PM

Quote:

Originally posted by Gav
Ian asked me to quote for a "Bow Extension" some time ago

You sure he said 'Bow' ?

Gav · 13-06-2005, 10:53 PM

Quote:

Originally posted by Jon Fuller
You sure he said 'Bow' ?

Mr F you been pokin around in his cockpit then??

Cookee · 14-06-2005, 09:00 AM

Quote:

Originally posted by Johnny Boat Dude
Is that whats on the front of that yellow P21 in the Ramsgate photos?

We made it at BananaShark (well actually Kevin made it at our factory in sunny Devon!).

BluFin · 14-06-2005, 09:26 AM

Yes they are a recovery AID, wont stop it but will all things being equal will help in the dig out, but it all depends how steep the entry is. In most cases they really work

Matt · 14-06-2005, 09:29 AM

They're still fugly though - only one I've seen that adds to the boat's appearance is on Wettpunkt.

jw. · 14-06-2005, 11:51 AM

Stick a bit of tube around there, that might help...

BluFin · 14-06-2005, 11:52 AM

Quote:

Originally posted by jw.
Stick a bit of tube around there, that might help...

Thunderbird Racing · 14-06-2005, 01:13 PM

yeap Rhino has some on his B23 to recover from a stuff, i need to make some for mine.

Pennpromo · 15-06-2005, 08:59 AM

In the mid 90s I drove a Frode 19 in what used to be 1.3 Litre. It had a terrific pair of anti stuff fins made from aerofol shaped aluminium at probably vaste expnse by Mr Pascoe and his team at Vulture Ventures.
They did actually work quite well, we even managed to bend them once.
Its all down to hull shape, they are all a compromise; To go fast into a big head sea you need very little forefoot and a fine bow to stop the waves deflecting the boat to far upwards, a little water in the bow tank, level trim and commitment should see you just cut the top of the waves off and run level. Going downwind a boat like this will need even more commitment as it does not have the volume in the hull forward to aid the recovery as the boat travels down a wave, hence anti stuff fins; first used by Fabio, "cheat to win" on some of his finer shaped monos. He even put them on some of the Iveco cats if I recall correctly.
When we built the Frode 23s for racing in about 1992 we put small alloy rails down the chines for the first 4 feet forward as they would aid this process without making the bow too full. Again you needed commitment and to be under power to make them work, back of and they would stuff. Many of the owners couldn't get the hang of it and so weren't as fast as they could be and complained that the boats wouldn't go in a following sea !
So in conclusion yes they do work, if they stick out far the forces involved can be immense so make them strong, and tie them together inside the hull. You need to know how to use them as well. don't put in too much angle of attack or you will tear them off with possibly catastophic damage to the hull.