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Title: Plank Release Post by: Bob Gray on February 26, 2018, 09:01:35 PM I was just told that several eastern area boats are using the ball bearing plank release setup. I’ve been told that it is basically two aluminum plates located with delrin balls and held together with nylon studs. I’ve come up with something very similar. Two aluminum plates, two 3/8” Delrin balls and two 3/8” nylon studs. My concern is over the studs. I don’t know if one is not enough or if two is too many. I don’t want the plank shearing off under heavy use with only one stud or not shearing off if you stuff a runner with two studs. Any advice would be much appreciated.
Title: Re: Plank Release Post by: eric_anderson on March 03, 2018, 07:40:43 PM Bob,
I have been sailing with this system for 12 years. Dave Fortier US4690 came up with it Call me at 860.367.7806 some time and I can talk you through our experiences with it. For balls we use 3/4" delrin balls, the bolt is a 3/8" fiber reinforced bolt. The balls take all the shear load and the bolt is just in tension until you hit something hard enough to roll the balls out of the sockets, then the bolt shears. Keep 2 spare bolts and 4 balls in the boat and you can put the plank back on in a few minutes. Eric Anderson us 5193 eric.anderson5193@att.net Title: Re: Plank Release Post by: keukaflyer on March 06, 2018, 08:25:38 AM Eric, have you or Dave had any situations where you have torn the plank off in this manner? If so, did everything come off clean as it should?
Title: Re: Plank Release Post by: eric_anderson on March 07, 2018, 03:25:53 PM I don't want to speak for Dave, but I have torn the plank off 3 times in 12 years. Once was a problem with the system that I did not realize I had, Basically I built a new plank and the press nut had a huge burr on it that striped the thread off the bolt and it released in a hard gybe.
I tore it off once in an epic hard spin/flip when we probably should not have been sailing and once when I hit a chunk of ice frozen onto the surface the runner did not make it over. In all cases I was able to immediately reset the plank and sail off. depending on exactly where the bolts shear off, you may be able to unscrew them out by hand, or you can use a screw driver to scratch a little slot in the bolt piece left in the nut and turn it out if it breaks off flush with the nut. I carry spare balls and bolts because you will never find the balls again. One thing to keep in mind is that if one side breaks loose, it twists the other side off also so you always need to replace both sides. Title: Re: Plank Release Post by: keukaflyer on March 07, 2018, 05:35:23 PM Thanks for sharing Eric.
Title: Re: Plank Release Post by: cuatroxcuatro on September 06, 2018, 09:26:31 AM Is anymore info available for this setup? I'm tring to figure this system out, an aluminum plate with a 3/4 inch recessions to accomodate the delrin balls? Having trouble finding more infor, tore my plank off the hull last year and it did a lot of damage and this system sounds effective.
cheers, Rob Title: Re: Plank Release Post by: TinkerSailor on November 29, 2018, 11:03:12 PM I had a crash last year and the welded studs didn't shear off :(.
Lots of damage! I would like to change to this system as I repair. Questions: How thick are the aluminum plates to start with? A full 3/8"? How many ball holes? What spacing? How much fore/aft adjustment do you get? What are the fiber reinforced bolts? Shear strength? Pictures would be awesome! Cheers, Leigh |