1981 C&C34. Sorry, got lazy on the signature. I believe the rods are 7/32 dia I understand that the rods were made by NavTec, referred to as NAV R505 This is a cold drawn rod from Nitronic 50 (22-13-5) Fu = 200,000 psi 7/32" dia = 0.0375 in^2 Breaking force = Fu x A = 7,500 lbs
Jeff Laman 1981 C&C34 "Harmony" Ludington, MI ________________________________ From: Bill Coleman via CnC-List <cnc-list@cnc-list.com> Sent: Monday, April 19, 2021 12:09 PM To: 'Stus-List' <cnc-list@cnc-list.com> Cc: Bill Coleman <colt...@gmail.com> Subject: Stus-List Re: Hydraulic backstay adjuster pressure? I am not sure the size boat we are talking about, but I think I would have been happy to have a relief valve set for 3K. Seems anything over that and you would be pulling the boat away from the front of your keel. I do like SailTec, and that unit is a great piece. Bill Coleman Entrada, Erie, PA From: Jeffrey A. Laman via CnC-List [mailto:cnc-list@cnc-list.com] Sent: Monday, April 19, 2021 11:07 AM To: Stus-List Cc: Jeffrey A. Laman Subject: Stus-List Re: Hydraulic backstay adjuster pressure? Hi All. Also wanted to comment on the pressure question. As I noted in my post about the NavTec - 10 failure, I have been examining all the issues that I more or less ignored or was happily ignorant of till now. One item was to determine the yield and breaking load on my backstay and correlating backstay shortening to load. If you do a little geometry and have knowledge of stress/force/strain/elongation, it is a fairly simple determination (I am a structural engineer). Others have provided photos of simple shortening measure devices, which I now intend to make and install. If others have photos, please share! But, one comment on pressure and force -- the pressure on the hydraulic backstay is directly related to force. So, if I trouble myself to read it, I will pay much more attention to the pressure on the gauge right in front of my face. At the moment, I don't recall what I read -- either NavTec or SailTec, or maybe both, 1000 psi = 1000 lbs force. The NavTec - 10 has a relief valve set to 4000 lbs. SailTec - 10 is 4750 lbs. Others with more knowledge may have more definitive information. Long story but I received the wrong SailTec - 10 the first time -- a custom unit for J105s that has a pressure relief at 3000 lbs. Excellent discussion, btw everybody! Jeff L. ________________________________ From: Edd Schillay via CnC-List <cnc-list@cnc-list.com> Sent: Sunday, April 18, 2021 3:04 PM To: Stus-List <cnc-list@cnc-list.com> Cc: Edd Schillay <e...@schillay.com> Subject: Stus-List Re: Hydraulic backstay adjuster pressure? Bruce, You may find this article interesting: https://www.sailingworld.com/getting-most-from-your-backstay/<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.sailingworld.com%2Fgetting-most-from-your-backstay%2F&data=04%7C01%7C%7Ca538f089ff564ba2ae6b08d9034daa01%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637544454357973714%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=EgTppT2C4rrGrgPGEUI2%2BZFqgP62yKmf4UV4oTCvFVg%3D&reserved=0> All the best, Edd Edd M. Schillay Captain of the Starship Enterprise C&C 37+ | Sail No: NCC-1701-B Venice Yacht Club | Venice Island, FL On Apr 18, 2021, at 2:05 PM, Bruce Whitmore via CnC-List <cnc-list@cnc-list.com<mailto:cnc-list@cnc-list.com>> wrote: Hello all With all of the discussions about hydraulic backstay adjusters, and mine being fixed (finally), where do most of you keep and use the pressure? At the dock vs. sailing and under what conditions? Thanks! Bruce Whitmore 1994 C&C 37/40+ Thanks to all of the subscribers that contributed to the list to help with the costs involved. If you want to show your support to the list - use PayPal to send contribution -- https://www.paypal.me/stumurray<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.paypal.me%2Fstumurray&data=04%7C01%7C%7Ca538f089ff564ba2ae6b08d9034daa01%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637544454357983668%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=X7C%2FzuPJsJi7hey8BhPEP8YAwOmzSyELhfXEUeKmpcY%3D&reserved=0> Thanks - Stu
Thanks to all of the subscribers that contributed to the list to help with the costs involved. If you want to show your support to the list - use PayPal to send contribution -- https://www.paypal.me/stumurray Thanks - Stu
