Scupper Size

Does anyone have the formula to calculate the scupper size requirements of a self bailing cockpit? It is ISO #11812 - standard for small craft. Thanks

 

ISO 11812 differentiates between self bailing cockpits and quick draining cockpits. The regulation deals with quick draining cockpits only. Do you have a copy of the reg? You need to know what design category you're going for, how big the cockpit is and a bunch of other stuff. You need to multiply you hull length by the maximum cockpit height and the freeboard amidships. Then divide your cockpit volume by that number to get a Kc value. Then you look up your Kc value on the chart and where it crosses the design category line it gives you the acceptable draining time and then you divide that by the cocpit volume and get T-ref which you look up on the table next to the kind of drain you want then look all the way down to the bottom of the table to get drain diameter in mm. And you'll have two one port one stbd. Who are you working for? Just curious.... OH that's right...Jeff

Ha ha ha and good luck with the new ISO stuff Ha ha ha ha ha.

e-mail me if you need help.

ha ha ha ha ha

 

Hey Thunderhead, can ya send me a copy of that ISO, that would be sweet. Possibly sweet unuff for a quick tour of the shop. Thanks

 

Since it's copyrighted, I don't think I can send you a copy. BUT I got a FREE copy from office of boating safety in Vancouver. They have permission to make copies apparently.

My e-mail to them went something like this. "What hours would I be able to visit in order to view the ISO documentation referenced in TP1332" And then they sent me the whole works in the mail!

If you get the cold shoulder from them, I'll see what I can do at my end.

cheers!