View previous topic :: View next topic |
Author |
Message |
dllee
Joined: 03 Jul 2009 Posts: 5329 Location: East Bay
|
Posted: Thu Mar 22, 2018 11:42 am Post subject: |
|
|
Go for it! Remember to use a rope leash from rear strap to loop around the vertical fin/mast to retain your foil after it rips out. I use 2mm Spectra. |
|
Back to top |
|
|
grantmac017
Joined: 04 Aug 2016 Posts: 946
|
Posted: Thu Mar 22, 2018 12:22 pm Post subject: |
|
|
There is no way you will get the center of gravity anywhere near the center of lift without a fuselage and rear wing.
But have fun replacing your fin box. |
|
Back to top |
|
|
dllee
Joined: 03 Jul 2009 Posts: 5329 Location: East Bay
|
Posted: Thu Mar 22, 2018 1:56 pm Post subject: |
|
|
Like riding a Bongo board.
That's why FRP's use the tail of the board for trim control.
Let's re invent the wheel. |
|
Back to top |
|
|
coachg
Joined: 10 Sep 2000 Posts: 3550
|
Posted: Fri Mar 23, 2018 8:35 am Post subject: |
|
|
dllee wrote: | Go for it! Remember to use a rope leash from rear strap to loop around the vertical fin/mast to retain your foil after it rips out. I use 2mm Spectra. |
Thanks for posting. I had totally forgot about that. I remember when Anders first started foiling out of Berkeley about 4 years ago he told me that they were hitting fish because the fish couldn't hear them coming so he had the same leash system on his foil.
Coachg |
|
Back to top |
|
|
dllee
Joined: 03 Jul 2009 Posts: 5329 Location: East Bay
|
Posted: Fri Mar 23, 2018 12:33 pm Post subject: |
|
|
In the fall, those7 foilers hit more than 3 fish a day, sometimes big ones..like rays and shark.
But watch for half sunken driftwood the most. |
|
Back to top |
|
|
ittiandro
Joined: 22 Nov 2009 Posts: 294
|
Posted: Sat Mar 24, 2018 11:10 am Post subject: |
|
|
Does the length of the wing's mast increase the forces ( torsional or other) on the fin box ?
I'd be inclined to think so, especially with those slender, almost 1 m long masts you see around. I believe they are likely to sway the longer the mast, but I am not too sure.
Perhaps by attaching my full D.I.Y contraption ( front and rear wing) directly on a 36 cm fin as a mast, I can reduce the stress on the US fin box to a safe level.
All I risk is may be that I have no lift off or that the board drifts downwind , because the fin is too short, as somebody suggested in this Forum, but it is better than breaking anything, as U2U2U2’s maths quite convincingly indicated.
There must be also a relationship between the wing's surface and the stress forces on the fin and fin box, in addition to the forces on the sail, isn't it ?
Also, I see that people bolt reinforcing plates around the fin box. I am sure they work, but I can't see how , because , from what I know, underneath the hard shell of the board there is soft foam or other similar material.
Thanks for your comments, as usual
Ittiandro |
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You can attach files in this forum You can download files in this forum
|
|
|