Fwd: Re: Keel retainer in double shear

From: Eric Zilbert (eezilbert@ucdavis.edu)
Date: Wed Jan 19 2000 - 10:02:47 PST


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Folks - below is an off list response from Jim Nolan to a question I had
following up on the correct alluminum shear pin to use for the P-19
centerboard hold down. I thought others could use the info. - Eric

>Eric:
>You want the pin to yield at 500 lbs single shear so it will give at 1000
>lbs double shear (as is the keel and trunk geometry). The two aluminum
>alloys I mentioned have about 13,000 PSI yield. This means 500lbs/13000PSI =
>.0385 in^2 cross sectional pin area. Divide the area by 3.14 (pi) and take
>the square root which gives a radius of .1107 in or a diameter of .2213
>inches. This means a 1/4" aluminum dowel of the previously mentioned
>aluminum alloys (shear approx 13,000 psi) will do the trick. You can post
>this to the Potter group if you desire. Thanks for your interest, I'm always
>glad to help.
>
>Jim Nolan P-19 #426 Panache
>

>>
>>So Jim, what should we use if we want to go to an aluminum shear pin - a
>>1/4" dowel? I am really interested in this as I am currently using a 1/4"
>>steel pin when I am concerned about keeping the board down. Thanks for
>>following up. - Eric
Eric E. Zilbert
Agricultural & Environmental Education Program
Dept. of Agronomy and Range Science, UCD
Davis, CA 95616 (530) 752-5943
>



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