When I was down testing the FX1, the hobie tigers had a dog lead to coil up the spinaker uphaul) taped to the boom near the mast luff. I mean a the extendable, self coiling type you see dog owners carrying - eg the dog runs, the coil unwinds, and the owner just presses a button and it coils back - taking the masses of lead back into a cosey hand held device which can be taped to the mast.
JUST LOOKED NEAT
Apparently Mitch Booth turned up with one at the F18 worlds - and all the shops were sold out of dog leads within 2 days
Regards
huw
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Re: Dog leads for cats
[Re: huw]
#5712 03/23/0209:30 AM03/23/0209:30 AM
Yep, I have seen this trip for a couple of years now on the Dutch beaches.
It does have the drawback of requiring a rather small diamerter line for the spi halyard when used.
However the technic use (lineair springs) is easy to homemake. Actually I was planning to make a setup myself for my own F16. I was also planning to make a document out of it and place in the Tech Corner of the F16 website. For I really dig the fact that F16 class has for some reason attracted innovation ex : Tramp launched spi, T-foil rudders (stealth), two piece Carbon masts (Bimare-Riba), lightweight Thrust bar rudder kick-up system and daggerboard raising setups (Taipan 4.9). I think it is thrilling to see ALL of these new things, as well as aspects of other classes like selftacking jibs, to be features on designs in a single class. The class is really going with the trend and presenting the newest in sailing. I would very much like to contribute to that.
I will post a few preliminairy pics I have on this page later.
Now lets hope to Bob develops the dolphin striker less beam from carbon succesfully.
Anyways
If you homemake it the retiever then it would probably costs somewhere around 20-25 Euros.
It would set on the outside of the rearbeam and coil up the excess halyard. The halyard would run over the trampoline from the cleat near the mast to the middle of the rearbeam and dive under the rearbeam to reach the winding coil. This line would constant be under slight tension and would wind up any excess line without pressing a button or anything.
See picture in next post.
Wouter
Wouter Hijink Formula 16 NED 243 (one-off; homebuild) The Netherlands
Picture one
[Re: huw]
#5713 03/23/0210:37 AM03/23/0210:37 AM
It is important to notice that on the right the diameter between two disks is larger than the between the other disks. The far left is used to coil up the halyard. The two drums on the right hand side as used for the tensioning system.
A small diameter bungee is run from the middle drum to the far right drum when the halyard is pulled out = retrieving the spinnaker. Because the diameters of the two drums on the right hand side is different, the bungee cord will be stretch with more or less a constant length per rotation of the drums. This, in combination with again the different diameters of the drums will result in a more or less constant torgue on the whole setup of drums. The torgue doesn't increase with pulling out more halyard line as would be the case with just a spring.
Notice that the bungee cord wants to be in the non stretched state and therefor on the drum with the smaller diameter. In order to go there the Halyard needs to be allowed to be retrieved to it's own drum hence a the bungee cord put a continious fore on the halyard trying to retrieve it.
Now when the spinnaker is set, the Halyard is pulled through the cleat near the mast and the excess of line on the trampoline is immediatley retrieved by the drums for this allows the bungeer cord to return to it's favoured state or drum.
Now the tension on the line is determined by the diameter of the drums and the stretching constant of the bungee cord.
Naturally the winding and unwinding of the drum may change diameters of the drums a bit too. So the dimension of the setup must take this into account.
I estimate that for a trampoline bag launched spi you'll have 10 mtr. (33 ft) or less halyard to retrieve. A drum of a diameter of 0,1 mtr. (1/3 ft) could retrieve a 5 mm = 1/5 inch halyard on 6 cm ( 2 inches) wide drum in two layers. This would only offset the force on the halyard by 10 % (10 cm diamter going to 11 cm diameter).
I expect a bungee cord of 2-3 mm ( 1/12 to 1/8 inch) to be enough for the tensioning. The bungee drums could than be about 2 to 3 cm wide (4/5 and 6/5 inch).
The whole setup would be less than 5 inches wide.
Assuming a max. CONSTANT stretching of 0,3 mtr. per 1 mtr = 30 % the diameter of the bungee drum would become.
Small drum = 0,1 mtr = 10 cm = 3,96 inches = say 3 inches
Big drum = 0,134 mtr. = 13,4 cm = 5,3 inches = 5 inches
The whole setup would be less than 0,15 mtr high = 6 inches.
And it would retrieve 10 mtr. halyard at a constant (give or take 10 % fluctuation) force. With a little experimentation the right diameter of the bungee drums or bungee stretch constant would be found.
I'm expecting this setup to greatly help my manual retrieval of the spin when I sail solo. I'm a little bit hesitant about using a snuffer because of the windage and I noticed that snuffer drops take quite a bit of fiddling and time to get that thing to go into the snuffer properly. If I do opt for a snuffer system then I will copy the trampoline launched system of teh Stealth.
This system has the extra advantage that it allows the jib to be sheeted of the trampoline just behind the mast which is the best place to make full use of the slot effect of the jib.
I would run the bag diagonal across my trampoline on the top side and make it so that I can run it on the other diagonal to optimize the platform for both port and starboard races and to align to centreline of the bag to the expected line of setting and retrieving of the spi.
But for now I will go for the manual system with bag o the trampoline. The Hobie bag ofcourse (see next post with attached photo) That bag works really well and I found that I can launch it immediately from the bag after pulling the loop and opening the bag.
Bob are you reading this too ? Use any of these idea on your custom F16 !!
Wouter
Wouter Hijink Formula 16 NED 243 (one-off; homebuild) The Netherlands
Re: Picture three
[Re: Wouter]
#5715 03/23/0211:16 AM03/23/0211:16 AM
The bag contains a bend rod that is hold into place by the bungeein the lid. The bag is opened extremely fast and can aslso be close in about 2 secs. Much faster than a baf with a zipper.
Wouter
Wouter Hijink Formula 16 NED 243 (one-off; homebuild) The Netherlands
Re: Picture three
[Re: Wouter]
#5716 03/25/0210:55 AM03/25/0210:55 AM