woensdag 12 juni 2013

tinkering (2)

As with my earlier furlers, I started to machine a cheap aluminium pulley on my lathe. I've altered the lathe a bit to be able to turn bigger workpieces, so I could make a bigger size furling drum (this one is about 10 cm diameter). Later on I drilled a lot of holes in the drum. Not only to make it lighter, but also to give the line in the drum a bit more bite. This is done by drilling holes half way in the part of the drum where the v-belt runs (the biggest holes, as can be seen in some pictures below).


The drum 'sits' on the top of the upper part of the swivel on a small edge. Better to show it, else nobody will understand.....

I waisted a lot of time trying to figure out the best way to feed the furling line to the drum and to retain the furling line. Tried to use dyneemaa rope, shockcord, aluminium rod, etc. to retain the line round the drum and a bored block of HMPE (UHWM) - just cutting board - to feed the line. In the end it turned out nothing worked nearly as good as my earlier solution: using a small stainless eye to feed the line in and out, and a retaining drum machined out of HMPE.
First prototype laid out with the three componenents:


I personally like this new design because the part which takes the big loads (the swivel) is totally independent from the parts of the furler that only need to do some low-load furling action. Even if the furling-parts fail, nothing bad will happen.
For a comparison: a picure of one of my earlier furler attempts and my new attempt. I believe the new one has the better looks.


And finally a small clip. Grip on the line is excellent when pulling, and even after pulling the line hard into the drum it releases with ease when the drum is spun on its own.
That's it for now. Next thing to do is to make a nice link to attach the furler to the rack in the bow of my boat. Till now I've used some stainless steel strips to link the furler to the rack, but my plan is to replace this by a sort of loop made of anti torsion rope. To be continued...

1 opmerking:

Alfonso Ruiz de Lobera zei

Beautiful piece of creativity!!!!
Thanks for sharing.
I will follow
Best Regards