Jib measurement clarifcation

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dave
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Jib measurement clarifcation

Post by dave » Thu Mar 08, 2012 1:14 pm

I'm designing a class jib for the 7.9 and noticed that the figures given for the max LP don't jibe with each other. The rules say: "Maximum LP of a jib with a headfoil tape is 9.94 feet, (9' 11 3/4").

9' 11 3/4" (9' 11.75") comes to 9.979 feet, while 9.94 feet would come to 9' 11.28" Which one is correct?

Thanks

Tom Elsen
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Re: Measurement clarifcation

Post by Tom Elsen » Fri Mar 09, 2012 2:05 am

Hey Dave.
It's pretty late, and I know you wanted a response quickly RE the genoa LP.
Give me a little time tomorrow.
I'll do my best to check with John as well.
Best wishes,
Tom

dave
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Location: Little Rock

Re: Jib measurement clarifcation

Post by dave » Fri Mar 09, 2012 9:37 am

Thanks a lot Tom, I appreciate it. It's not a "life and death" matter, but I do need to finalize the design file. We're only talking a tad under .5", but legal is legal and the other ain't!!!!

Dave

dave
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Location: Little Rock

Re: Jib measurement clarifcation

Post by dave » Fri Mar 09, 2012 9:40 am

I just noticed that I misspelled Jib.................................. I'd fix it from my end if there was an edit option. Can you do that please? I never have been a keyboard Ace!!!! :oops: :oops: :oops:

Dave

>>>>>Done. FYI, there is an edit option.

Tom Elsen
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Re: Jib measurement clarifcation

Post by Tom Elsen » Fri Mar 09, 2012 5:21 pm

Working on it. Trying to find out where the error is exactly. That will dictate the solution.
Best wishes,
Tom

dave
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Re: Jib measurement clarifcation

Post by dave » Sat Mar 10, 2012 10:43 am

Thanks for the update Tom, no worries here. :wink: Looks like a simple math error or typo, but who knows which way and on which figure..............................

Dave

dave
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Re: Jib measurement clarifcation

Post by dave » Sun Mar 11, 2012 12:04 pm

Just to be sure; we're talking class jib here, not Genoa. I'm only touching on this because you said "Genoa" in you first reply.

Thanks again Tom,

Dave :wink:

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Tim Bosma
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Re: Jib measurement clarifcation

Post by Tim Bosma » Sun Mar 11, 2012 8:30 pm

Dave,
Every time we have set up templates to measure at an event, we have used the decimal measurements from the rules. If you use 9.94' you will be certain to be Class legal. You will also notice that all other sail measurements are in decimal form and only a few in fractional notation (and that is in parentheses).
Thanks,
Tim Bosma, Bosun
Hot Tamale Racing
boz@htr477.com
S2 7.9's : #477

dave
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Location: Little Rock

Re: Jib measurement clarifcation

Post by dave » Mon Mar 12, 2012 9:18 am

Okay Tim, thanks for that.

Dave

Tom Elsen
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Re: Jib measurement clarifcation

Post by Tom Elsen » Thu Mar 15, 2012 1:36 pm

Dave - missing one vote on the Jib issue. Should have it solved tonight.
Best wishes,
Tom

dave
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Re: Jib measurement clarifcation

Post by dave » Thu Mar 15, 2012 3:51 pm

Thanks Tom. The design file(s) is/are already at Dimension Polyant, by I can trim the membrane to size as always.

Dave

Tom Elsen
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Re: Jib measurement clarifcation

Post by Tom Elsen » Sat Mar 17, 2012 11:35 am

The rule will be corrected and will be consistent with How we measure genoas (3/4" more allowed LP for hanked sails).
Old sails will be grandfathered in. But since those will have shrunk, we expect few would ever create a problem in the first place.

Here is the new text headfoil jibs under 2.5.C.1

Maximum LP for a jib using a headfoil tape is 9.94 feet. Headfoil jibs produced prior to 3/15/2012, are permitted a max LP of 9' 11 3/4" due to an error in the old rule. 

It will be up / corrected in the rules document as soon as Tim gets back.

Thanks for catching the original error Dave.
Best wishes,
Tom

dave
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Re: Jib measurement clarifcation

Post by dave » Sat Mar 17, 2012 12:07 pm

Thanks for the clarification Tom. :wink:

Dave

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Tim Bosma
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Re: Jib measurement clarifcation

Post by Tim Bosma » Sun Mar 25, 2012 7:51 pm

The updated Class Rules are now posted on the Class Web Site.
Thanks,
Tim Bosma, Bosun
Hot Tamale Racing
boz@htr477.com
S2 7.9's : #477

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