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Author Topic: Plank Release  (Read 977 times)
Bob Gray
Class Member
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Posts: 183


« 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. Iíve been told that it is basically two aluminum plates located with delrin balls and held together with nylon studs. Iíve come up with something very similar. Two aluminum plates, two 3/8Ē Delrin balls and two 3/8Ē nylon studs. My concern is over the studs. I donít know if one is not enough or if two is too many. I donít 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.
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eric_anderson
Newbie

Posts: 42


« Reply #1 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
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keukaflyer
Newbie

Posts: 28


« Reply #2 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?
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DN US637
eric_anderson
Newbie

Posts: 42


« Reply #3 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.
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keukaflyer
Newbie

Posts: 28


« Reply #4 on: March 07, 2018, 05:35:23 PM »

Thanks for sharing Eric.
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DN US637
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