I rebuilt my entire transom after ripping out one of the attachments I’ll post pictures. I don’t go above 2700
Rich Hulit Kindred C&C 37+ Rich Hulit (917) 854-5537 > On Aug 2, 2018, at 8:41 PM, [email protected] wrote: > > Send CnC-List mailing list submissions to > [email protected] > > To subscribe or unsubscribe via the World Wide Web, visit > http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com > or, via email, send a message with subject or body 'help' to > [email protected] > > You can reach the person managing the list at > [email protected] > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of CnC-List digest..." > > > Today's Topics: > > 1. Re: 37+ Backstay tension (Dennis C.) > 2. Re: 37+ Backstay tension (Gary Russell) > 3. Re: 37+ Backstay tension (Josh Muckley) > 4. Re: 37+ Backstay tension (Gary Russell) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Thu, 2 Aug 2018 19:13:26 -0500 > From: "Dennis C." <[email protected]> > To: CnClist <[email protected]> > Subject: Re: Stus-List 37+ Backstay tension > Message-ID: > <canir+yszmhisxuz4bbqbjvznew8jsqpqben42hryn3dzbwp...@mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > I never go by lbs, psi, whatever. What matters is sail shape and forestay > sag (or lack thereof). I have a small dinghy batten taped to the AFT side > of the cylinder of the backstay adjuster. On the batten are small wraps of > green, yellow, red and black tape. These are positioned so the fitting on > the backstay will line up with them when the rig is tensioned. On an > upwind leg of a race, we tension the forestay to shape the sail how we like > Send CnC-List mailing list submissions to > [email protected] > > To subscribe or unsubscribe via the World Wide Web, visit > http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com > or, via email, send a message with subject or body 'help' to > [email protected] > > You can reach the person managing the list at > [email protected] > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of CnC-List digest..." > > > Today's Topics: > > 1. Re: 37+ Backstay tension (Dennis C.) > 2. Re: 37+ Backstay tension (Gary Russell) > 3. Re: 37+ Backstay tension (Josh Muckley) > 4. Re: 37+ Backstay tension (Gary Russell) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Thu, 2 Aug 2018 19:13:26 -0500 > From: "Dennis C." <[email protected]> > To: CnClist <[email protected]> > Subject: Re: Stus-List 37+ Backstay tension > Message-ID: > <canir+yszmhisxuz4bbqbjvznew8jsqpqben42hryn3dzbwp...@mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > I never go by lbs, psi, whatever. What matters is sail shape and forestay > sag (or lack thereof). I have a small dinghy batten taped to the AFT side > of the cylinder of the backstay adjuster. On the batten are small wraps of > green, yellow, red and black tape. These are positioned so the fitting on > the backstay will line up with them when the rig is tensioned. On an > upwind leg of a race, we tension the forestay to shape the sail how we like > it, then look at the batten and take note of which tape mark the fitting > lines up with. On the next upwind leg, if the wind and waves are the same, > we tension the rig to the same piece of tape. > > Green = light breeze. Yellow = moderate breeze. Red = heavy breeze. > Black = OMG, we're going to die! > > The tape wraps on the batten are MUCH easier to see than the gauge. > > If you look closely, you can see the batten on the aft side of the cylinder > here: > > https://drive.google.com/open?id=1zzjRreszZF9YCbb5zBfTLGBuVtim4mcZ > > That's not a good picture. It was taken to show the jury rig to tension > the backstay after the adjuster lost the top seal. :( > > Dennis C. > Touche' 35-1 #83 > Mandeville, LA > > On Thu, Aug 2, 2018 at 4:52 PM, Gary Russell via CnC-List < > [email protected]> wrote: > >> Does anyone know the maximum back stay tension allowed on the C&C >> 37+. My problem is the hydraulic back stay adjuster pressure gauge has >> failed and I don't even know what the maximum pressure spec allowed is, >> anyway. I'm concerned that at least one owner has had the attachment >> points on the transom fail presumably due to excessive tension/pressure. >> Frankly, the attachment points don't instill a lot of confidence as there >> aren't any backing plate; just a couple of holes drilled in the hull. I'd >> feel more comfortable putting a Loos gauge on the wire and calibrate the >> extension of the back stay adjuster to it. Any thoughts / ideas out there? >> >> Live Slow / Sail Fast, >> Gary >> S/V Kaylarah >> '90 C&C 37+ >> East Greenwich, RI, USA >> ~~~~~~~_/)~~~~~~ >> >> >> _______________________________________________ >> >> Thanks everyone for supporting this list with your contributions. Each >> and every one is greatly appreciated. If you want to support the list - >> use PayPal to send contribution -- https://www.paypal.me/stumurray >> >> >> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://cnc-list.com/pipermail/cnc-list_cnc-list.com/attachments/20180802/9ffd1246/attachment-0001.html> > > ------------------------------ > > Message: 2 > Date: Thu, 2 Aug 2018 20:29:38 -0400 > From: Gary Russell <[email protected]> > To: "C&C List" <[email protected]> > Subject: Re: Stus-List 37+ Backstay tension > Message-ID: > <CABgkXPJpEg8dK=4J1KeJbaHbpasiVW9gCfMoUj6w=dram5w...@mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > Dennis, > I agree, and have a "calibrated" batten on mine as well, but I still > need the designer to tell me when I am exceeding the design limits of the > hard point where the back stay attaches to the transom. > > Gary > S/V Kaylarah > '90 C&C 37+ > East Greenwich, RI, USA > > ~~~~~~~_/)~~~~~~ > > > On Thu, Aug 2, 2018 at 8:13 PM, Dennis C. via CnC-List < > [email protected]> wrote: > >> I never go by lbs, psi, whatever. What matters is sail shape and forestay >> sag (or lack thereof). I have a small dinghy batten taped to the AFT side >> of the cylinder of the backstay adjuster. On the batten are small wraps of >> green, yellow, red and black tape. These are positioned so the fitting on >> the backstay will line up with them when the rig is tensioned. On an >> upwind leg of a race, we tension the forestay to shape the sail how we like >> it, then look at the batten and take note of which tape mark the fitting >> lines up with. On the next upwind leg, if the wind and waves are the same, >> we tension the rig to the same piece of tape. >> >> Green = light breeze. Yellow = moderate breeze. Red = heavy breeze. >> Black = OMG, we're going to die! >> >> The tape wraps on the batten are MUCH easier to see than the gauge. >> >> If you look closely, you can see the batten on the aft side of the >> cylinder here: >> >> https://drive.google.com/open?id=1zzjRreszZF9YCbb5zBfTLGBuVtim4mcZ >> >> That's not a good picture. It was taken to show the jury rig to tension >> the backstay after the adjuster lost the top seal. :( >> >> Dennis C. >> Touche' 35-1 #83 >> Mandeville, LA >> >> On Thu, Aug 2, 2018 at 4:52 PM, Gary Russell via CnC-List < >> [email protected]> wrote: >> >>> Does anyone know the maximum back stay tension allowed on the C&C >>> 37+. My problem is the hydraulic back stay adjuster pressure gauge has >>> failed and I don't even know what the maximum pressure spec allowed is, >>> anyway. I'm concerned that at least one owner has had the attachment >>> points on the transom fail presumably due to excessive tension/pressure. >>> Frankly, the attachment points don't instill a lot of confidence as there >>> aren't any backing plate; just a couple of holes drilled in the hull. I'd >>> feel more comfortable putting a Loos gauge on the wire and calibrate the >>> extension of the back stay adjuster to it. Any thoughts / ideas out there? >>> >>> Live Slow / Sail Fast, >>> Gary >>> S/V Kaylarah >>> '90 C&C 37+ >>> East Greenwich, RI, USA >>> ~~~~~~~_/)~~~~~~ >>> >>> >>> _______________________________________________ >>> >>> Thanks everyone for supporting this list with your contributions. Each >>> and every one is greatly appreciated. If you want to support the list - >>> use PayPal to send contribution -- https://www.paypal.me/stumurray >>> >>> >>> >> >> _______________________________________________ >> >> Thanks everyone for supporting this list with your contributions. Each >> and every one is greatly appreciated. If you want to support the list - >> use PayPal to send contribution -- https://www.paypal.me/stumurray >> >> >> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://cnc-list.com/pipermail/cnc-list_cnc-list.com/attachments/20180802/e46c9780/attachment-0001.html> > > ------------------------------ > > Message: 3 > Date: Thu, 2 Aug 2018 20:33:00 -0400 > From: Josh Muckley <[email protected]> > To: "C&C List" <[email protected]> > Subject: Re: Stus-List 37+ Backstay tension > Message-ID: > <ca+zacrds1op7qttwmrjdebyrtfx9j8wnhnoakxvbs6hpgh7...@mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > Page 68 of the manual pdf file which I linked before has the pre-load and > max load limits. > > Again I am corrected in my preconceived notions regarding the correlation > between a hydraulic gauge and the tensile load on the back stay. > > Josh > > On Thu, Aug 2, 2018, 8:13 PM Gary Russell via CnC-List < > [email protected]> wrote: > >> Hi Josh, >> Where did you find the 4125 or 5000 lb. limit? I don't see that in >> the Owners Manual? Is the 4125 lb. limit for the lower angled segments of >> the the back stay or the upper vertical part. You can't simply measure the >> port back stay tension and multiply by two, because of the angle between >> the two. You would have to measure the angle and apply some trig to get >> the right value. Mike Cotton's boat was the one I was referring to in my >> email above. >> >> Gary >> >> ~~~~~~~_/)~~~~~~ >> >> >> On Thu, Aug 2, 2018 at 6:31 PM, Josh Muckley via CnC-List < >> [email protected]> wrote: >> >>> The manual says limit to 4125lbs and then says absolute max of 5000lbs. >>> https://drive.google.com/file/d/0B8pEh5lnvP1ySXFBdDhrX0ZaMzNnazViYkZzRVRoODlSSUd3/view?usp=drivesdk >>> >>> I never considered that the hydraulic pressure psi could/would be >>> independent of tensile load. When I had my hydraulic pump rebuilt by Lew >>> Townsend he tried to adjust the relief valve but mine adjustment knob was >>> seized. He gave up and just hydro-tested it anyway. He found that the >>> relief was roughly 3500. I rarely go over 2500. Now that I have to >>> consider the corollary between psi and lbs I'll be pulling out my Loose >>> tension gauge and get back to you. Since it is split I'll remember to add >>> together or double a single. >>> >>> As for the attachment to the transom, I agree it does seem slightly poor >>> engineering. In fact when we were shopping around the first boat looked at >>> wad named Blue Pearl and had been owned by Mike Cotton who was and may >>> still be on this list. It was evident that some past event had caused the >>> port aft attachment to separate the flat horizontal (cap) part of the >>> fiberglass casting from the curved (body) potion. The hydraulic pump was a >>> single piston and pump combo that attached between the port anchor amd the >>> port side of the back stay. Evidently a sheave communicated the tension to >>> the stbd size at the point where the single rod attached from the mast >>> head. It seemed as though maybe the sheave didn't roll smoothly and failed >>> to split the tension evenly between the port and stbd anchor on the >>> transom. That of the fiberglass layup was uneven and the port side was >>> just coincidentally weaker. >>> >>> I was attentive to this weakness when I continued shopping and found Sea >>> Hawk. I discussed the issue with the PO and he showed his engineering >>> answer. >>> >>> https://drive.google.com/folderview?id=0B8pEh5lnvP1ybDFIZ0ZZTU1XdHM >>> >>> I'm not convinced that it is "correct" but it is certainly better than >>> nothing. I had decided years ago that I was going to engineer a >>> reinforcement of my own with some G10 FPR. I still have the G10 but have >>> never acted on the project. My idea was to back the entire corner of the >>> transom with 1/2" G10 FRP by epoxying it in place and then fill the >>> attachment cavity (the bump out) with epoxy. Longer u-bolts and a spade or >>> mortise bit to countersink a flat load bearing "pad" for the washers and >>> nuts to drive against and I would be done. >>> >>> Josh Muckley >>> S/V Sea Hawk >>> 1989 C&C 37+ >>> Solomons, MD >>> >>> >>> >>> >>> On Thu, Aug 2, 2018, 5:53 PM Gary Russell via CnC-List < >>> [email protected]> wrote: >>> >>>> Does anyone know the maximum back stay tension allowed on the C&C >>>> 37+. My problem is the hydraulic back stay adjuster pressure gauge has >>>> failed and I don't even know what the maximum pressure spec allowed is, >>>> anyway. I'm concerned that at least one owner has had the attachment >>>> points on the transom fail presumably due to excessive tension/pressure. >>>> Frankly, the attachment points don't instill a lot of confidence as there >>>> aren't any backing plate; just a couple of holes drilled in the hull. I'd >>>> feel more comfortable putting a Loos gauge on the wire and calibrate the >>>> extension of the back stay adjuster to it. Any thoughts / ideas out there? >>>> >>>> Live Slow / Sail Fast, >>>> Gary >>>> S/V Kaylarah >>>> '90 C&C 37+ >>>> East Greenwich, RI, USA >>>> ~~~~~~~_/)~~~~~~ >>>> >>>> _______________________________________________ >>>> >>>> Thanks everyone for supporting this list with your contributions. Each >>>> and every one is greatly appreciated. If you want to support the list - >>>> use PayPal to send contribution -- https://www.paypal.me/stumurray >>>> >>>> >>> _______________________________________________ >>> >>> Thanks everyone for supporting this list with your contributions. Each >>> and every one is greatly appreciated. If you want to support the list - >>> use PayPal to send contribution -- https://www.paypal.me/stumurray >>> >>> >>> >> _______________________________________________ >> >> Thanks everyone for supporting this list with your contributions. Each >> and every one is greatly appreciated. If you want to support the list - >> use PayPal to send contribution -- https://www.paypal.me/stumurray >> >> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://cnc-list.com/pipermail/cnc-list_cnc-list.com/attachments/20180802/cb089bfc/attachment-0001.html> > > ------------------------------ > > Message: 4 > Date: Thu, 2 Aug 2018 20:40:42 -0400 > From: Gary Russell <[email protected]> > To: "C&C List" <[email protected]> > Subject: Re: Stus-List 37+ Backstay tension > Message-ID: > <cabgkxpl5e6gphkzqaz81geos37uzl0h36+uh8raka4yqtmp...@mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > Hi Josh, > Oops! I missed that. I looked in the chapter about rigging and > didn't find it there. Silly me! I even searched for the number 4125 and > found nothing. I guess the document is an image rather than text. Now the > question, is that the tension in the vertical part of the back stay? I > guess, the safest assumption is that it is. > > Gary > > > ~~~~~~~_/)~~~~~~ > > > On Thu, Aug 2, 2018 at 8:33 PM, Josh Muckley via CnC-List < > [email protected]> wrote: > >> Page 68 of the manual pdf file which I linked before has the pre-load and >> max load limits. >> >> Again I am corrected in my preconceived notions regarding the correlation >> between a hydraulic gauge and the tensile load on the back stay. >> >> Josh >> >> On Thu, Aug 2, 2018, 8:13 PM Gary Russell via CnC-List < >> [email protected]> wrote: >> >>> Hi Josh, >>> Where did you find the 4125 or 5000 lb. limit? I don't see that in >>> the Owners Manual? Is the 4125 lb. limit for the lower angled segments of >>> the the back stay or the upper vertical part. You can't simply measure the >>> port back stay tension and multiply by two, because of the angle between >>> the two. You would have to measure the angle and apply some trig to get >>> the right value. Mike Cotton's boat was the one I was referring to in my >>> email above. >>> >>> Gary >>> >>> ~~~~~~~_/)~~~~~~ >>> >>> >>> On Thu, Aug 2, 2018 at 6:31 PM, Josh Muckley via CnC-List < >>> [email protected]> wrote: >>> >>>> The manual says limit to 4125lbs and then says absolute max of 5000lbs. >>>> https://drive.google.com/file/d/0B8pEh5lnvP1ySXFBdDhrX0ZaMzNna >>>> zViYkZzRVRoODlSSUd3/view?usp=drivesdk >>>> >>>> I never considered that the hydraulic pressure psi could/would be >>>> independent of tensile load. When I had my hydraulic pump rebuilt by Lew >>>> Townsend he tried to adjust the relief valve but mine adjustment knob was >>>> seized. He gave up and just hydro-tested it anyway. He found that the >>>> relief was roughly 3500. I rarely go over 2500. Now that I have to >>>> consider the corollary between psi and lbs I'll be pulling out my Loose >>>> tension gauge and get back to you. Since it is split I'll remember to add >>>> together or double a single. >>>> >>>> As for the attachment to the transom, I agree it does seem slightly poor >>>> engineering. In fact when we were shopping around the first boat looked at >>>> wad named Blue Pearl and had been owned by Mike Cotton who was and may >>>> still be on this list. It was evident that some past event had caused the >>>> port aft attachment to separate the flat horizontal (cap) part of the >>>> fiberglass casting from the curved (body) potion. The hydraulic pump was a >>>> single piston and pump combo that attached between the port anchor amd the >>>> port side of the back stay. Evidently a sheave communicated the tension to >>>> the stbd size at the point where the single rod attached from the mast >>>> head. It seemed as though maybe the sheave didn't roll smoothly and failed >>>> to split the tension evenly between the port and stbd anchor on the >>>> transom. That of the fiberglass layup was uneven and the port side was >>>> just coincidentally weaker. >>>> >>>> I was attentive to this weakness when I continued shopping and found Sea >>>> Hawk. I discussed the issue with the PO and he showed his engineering >>>> answer. >>>> >>>> https://drive.google.com/folderview?id=0B8pEh5lnvP1ybDFIZ0ZZTU1XdHM >>>> >>>> I'm not convinced that it is "correct" but it is certainly better than >>>> nothing. I had decided years ago that I was going to engineer a >>>> reinforcement of my own with some G10 FPR. I still have the G10 but have >>>> never acted on the project. My idea was to back the entire corner of the >>>> transom with 1/2" G10 FRP by epoxying it in place and then fill the >>>> attachment cavity (the bump out) with epoxy. Longer u-bolts and a spade or >>>> mortise bit to countersink a flat load bearing "pad" for the washers and >>>> nuts to drive against and I would be done. >>>> >>>> Josh Muckley >>>> S/V Sea Hawk >>>> 1989 C&C 37+ >>>> Solomons, MD >>>> >>>> >>>> >>>> >>>> On Thu, Aug 2, 2018, 5:53 PM Gary Russell via CnC-List < >>>> [email protected]> wrote: >>>> >>>>> Does anyone know the maximum back stay tension allowed on the C&C >>>>> 37+. My problem is the hydraulic back stay adjuster pressure gauge has >>>>> failed and I don't even know what the maximum pressure spec allowed is, >>>>> anyway. I'm concerned that at least one owner has had the attachment >>>>> points on the transom fail presumably due to excessive tension/pressure. >>>>> Frankly, the attachment points don't instill a lot of confidence as there >>>>> aren't any backing plate; just a couple of holes drilled in the hull. I'd >>>>> feel more comfortable putting a Loos gauge on the wire and calibrate the >>>>> extension of the back stay adjuster to it. Any thoughts / ideas out >>>>> there? >>>>> >>>>> Live Slow / Sail Fast, >>>>> Gary >>>>> S/V Kaylarah >>>>> '90 C&C 37+ >>>>> East Greenwich, RI, USA >>>>> ~~~~~~~_/)~~~~~~ >>>>> >>>>> _______________________________________________ >>>>> >>>>> Thanks everyone for supporting this list with your contributions. Each >>>>> and every one is greatly appreciated. If you want to support the list - >>>>> use PayPal to send contribution -- https://www.paypal.me/stumurray >>>>> >>>>> >>>> _______________________________________________ >>>> >>>> Thanks everyone for supporting this list with your contributions. Each >>>> and every one is greatly appreciated. If you want to support the list - >>>> use PayPal to send contribution -- https://www.paypal.me/stumurray >>>> >>>> >>>> >>> _______________________________________________ >>> >>> Thanks everyone for supporting this list with your contributions. Each >>> and every one is greatly appreciated. If you want to support the list - >>> use PayPal to send contribution -- https://www.paypal.me/stumurray >>> >>> >> _______________________________________________ >> >> Thanks everyone for supporting this list with your contributions. Each >> and every one is greatly appreciated. If you want to support the list - >> use PayPal to send contribution -- https://www.paypal.me/stumurray >> >> >> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://cnc-list.com/pipermail/cnc-list_cnc-list.com/attachments/20180802/3cae0b38/attachment.html> > > ------------------------------ > > Subject: Digest Footer > > _______________________________________________ > CnC-List mailing list > [email protected] > http://cnc-list.com/mailman/listinfo/cnc-list_cnc-list.com > > > ------------------------------ > > End of CnC-List Digest, Vol 151, Issue 16 > ***************************************** _______________________________________________ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
