Convert to Dyneema backstay
Printed From: myHanse.com
Category: Hints & Tips
Forum Name: 320
Forum Description: 320 Hints and Tips
URL: https://www.myhanse.com/forum_posts.asp?TID=4871
Printed Date: 27 March 2026 at 03:08
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Topic: Convert to Dyneema backstay
Posted By: shaukaas
Subject: Convert to Dyneema backstay
Date Posted: 08 March 2011 at 12:21
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One of this seasons upgrade plans for my 320 is to replace the 5mm backstay with a Dyneema version. However, as always, my head is full of questions: 1. Is a 6mm "single braided" Dyneema similar to 5mm wire? 2. How much should the involved block in my aft-stay arrangement be able to withstand? (What size of block should I aim for?) 3. Has anyone carried out a similar upgrade? ------------- S/Y Nadun - Hanse 320#171 LG3600 - NOR13510 |
Replies:
Posted By: H8jer
Date Posted: 08 March 2011 at 12:48
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Personally I would not replace any wire in the standing rigging to Dynamee.
On yachts with Runners (Danish word is Bagstag) and Backstag, one can switch the runners to Dynamee, but it is not always without problems. Some X-99 sailors have tried to switch to Dynamee but walked away from it again. I think a wire will be more weather-resistant long-term and the weight saving will not be in proportion to the risk of losing the mast because the dynamee had become tired. But if You go ahead replacing, it would be interesting to hear your experience. Greetings ------------- Hanse 370#487 30HP 3-cabin |
Posted By: Raptor
Date Posted: 08 March 2011 at 14:05
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stian, 1. yes. 6mm is sufficient.
2. use e.g. ronstan orbit halyard block series 75.
3. plan to do the same and have already bought all the blocks involved in order to end up at 32:1 purchase.
good luck.
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Posted By: shaukaas
Date Posted: 08 March 2011 at 15:55
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Great news, Raptor! What part numbers did you buy? Any pictures or drawings (sketches?) on your (planned?) installation? I'll do the conversion, but won't throw away my old steely' Dan backstay - as it may come in handy one day. My boat is de-rigged every winter anyways, so I will have plenty of opportunities to inspect the state of the rope. I this conversion doesn't work as planned, I'll simply switch back next season... ------------- S/Y Nadun - Hanse 320#171 LG3600 - NOR13510 |
Posted By: Raptor
Date Posted: 08 March 2011 at 17:19
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Stian,
You can make a really expensive one using only blocks from Ronstan or you can do like me go for the budget model by using Selden blocks. I only bought one block from Ronstan which is the huge one at the end of the backstay. Simple drawing: 
Nr. 1: Ronstan Orbit Halyard block art no. RF79108 Nr. 2: Selden PBB50 Single block art. no. 405-001-01R Nr. 3: Selden PBB50 Single block art. no. 405-001-01R Nr. 4: Selden PBB50 Tripleblock art. no. 405-001-07R Nr. 5: Selden PBB50 Trippleblock with becket and cam art. no. 405-001-10R The purchase gained is maybe a little more than initially intended. Sorry for the sketch showing a horizontal rather than in a portrait layout. |
Posted By: shaukaas
Date Posted: 08 March 2011 at 17:41
Thanks for the info! But... http://webshop.skaane.no/main.aspx?page=article&artno=833075 - Veil inkl mva : 3 100,00 ??? ------------- S/Y Nadun - Hanse 320#171 LG3600 - NOR13510 |
Raptor wrote:Posted By: Raptor
Date Posted: 08 March 2011 at 18:12
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I have got the art. no. wrong.
Think both of these are sufficient: RF74108 nok 912.- RF64108 nok 681.- I bought the last and cheapest one. |
Posted By: Rubato
Date Posted: 08 March 2011 at 19:40
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Consider adding a cover to the line for protection from UV, etc. Have you considered PBO?
I have a PBO backstay on my 400 and it has a black covering to protect it. Also, there are special fittings on the end to tie in properly with the rigging. I suggest you talk to a professional rigger about this if you haven't already.
I won't get into why I did this but I wouldn't necessarily do it it again. I'm wondering what your motivation is?
Steve
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Posted By: shaukaas
Date Posted: 08 March 2011 at 22:12
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I will indeed talk to a professional rigger regarding these details, and have also been talking to him at several occasions and mentioned this. From previous, and current, work-experience - I can tell that what most professionals charge you $100-150 an hour (Norwegian prices, though) - can easily be done yourself absolutely for free, and also provide me with some extra knowledge. As my current position offers a 1/1 schedule - I've got plenty off spare-time to "take from" for my little boat project, in addition to being my number 1 interest... Compared to the work them "professionals" have performed on other Hanse's in my area, including my own, I'm 100% sure that what I've done on my boat myself holds an equal standard, or even better. Because I've got the time, the keen interest - and spends hours of investigation and reading before doing any major un-reversible change - I'm confident not "ruining" the sloop to a piece of unrecognizable white plastic.  Certainly forums like e.g. Myhanse.com provides the "base" of tips and ideas, supported by different articles and documents on the web. So far this has proven to be "far beyond" good - and in the rare cases where I've been discussing technical details with them pro's - I've been able to prove them wrong. But one day, this may prove to be wrong... My motivation(s) for fitting a Dyneema backstay are, in prioritized order: 1. Get the backstay off my mainsail when tacking/jibbing. (And also to be prepared for my new main, when I've got them $ to invest in high-tech clothing...) 2. Get a better trim of my 9/10 rig. (Which leads us into my no 3.) 3. Better "ratio". (Today I would have to use the ST'er to tighten it up.) 4. Have a non-stretchable sheet for adjusting the backstay; today's cheap polyester bungee cord, probably cost me 1/10th of a secound for every 100 nautical mail I race...  5. Get a "flying lead" 450MHz antenna implemented for my CDMA-based onboard Ice.net network connection. 6. The looks.  ------------- S/Y Nadun - Hanse 320#171 LG3600 - NOR13510 |
Posted By: Raptor
Date Posted: 08 March 2011 at 22:40
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I haven't gone through the motions of dismantling my rig yet. When I finally do that i will fix a batten at the top of the mast with a small loop at the end and let the backstay run through the loop. This will lift the backstay away from the main when e.g., sailing in little wind. I had a similar solution on my Albin Express.
Selden got an off the shelf piece but not ready installable on my Sparcraft rig. |
Posted By: Rubato
Date Posted: 09 March 2011 at 05:58
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Shaukaas,
I totally agree with your comments regarding doing it yourself and the quality of some trades and their workmanship. More knowledge of the boat itself is handy in all sorts of situation.
Since you mentioned it, my motivator is also your #1. My racing mainsail has a roach and the backstay interferes with tacking and gybing. Even with the PBO backstay, it still interferes in light air.
If you're thinking this way then you're likely racing. In a light air race you will have to assign someone to release the backstay as you tack. This is not that easy as just releasing it from a cam cleat is not good enough. They will have to pull a significant amount of line through all the blocks so that the backstay is flopping around. THen as the main sail tacks or gybes the will have to try to flip the backstay over the leach of the main. We rarely accomplish this.
In heavy breeze it's not an issue. You don't touch the backstay and the main tacks and gybes fine. Extra reinforcement on the main and on the backstay in the area of rubbing is likely warranted.
I'm not saying you shouldn't do it. I'm just letting you know what I find the issues are. I spent an extra $1200 for this type of backstay and in my opinion it's no different than having the wire (a bit lighter perhaps but on an 9000kg boat who cares). I guess it does provide endless entertainment in light breeze watching some poor crew member trying to unstick it from the main....
The most effective way of dealing with mainsails with significant roach is the masthead whip. Not sure what it would take to set something like that up.
Steve
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Posted By: Raptor
Date Posted: 09 March 2011 at 07:07
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Rubato,
Solution to no. 1 is a backstay flicker. Either buy one from e.g., Selden but one might have to do some modifications if you´re having a non Selden rig. The other solution is to attache a stiff sailbatten which will do the same job at a cheaper price. |
Posted By: shaukaas
Date Posted: 09 March 2011 at 10:05
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I do anticipate in races from time to time with my 320, but still I'm aiming for better results. I guess most of it depends of myself, but still - being a "equipmentinator" the time has now come to modifying the backstay... Amongst a handful of other projects... As I'm also sailing a lot of single and doublehanded, this is actually a "huge" practical problem. So I'll also install a whip, but I guess the weight of a wire-assembly will be too much for the whip? Raptor, Have you checked out the whip-assembly's that Benns.se have in their webshop, or talked to Ed Tadzik at http://www.southerncross.no/ - Sothern Cross Spars? ------------- S/Y Nadun - Hanse 320#171 LG3600 - NOR13510 |
Posted By: Raptor
Date Posted: 09 March 2011 at 10:57
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Stian,
As I have not really studied the mastop and how it is designed, I must say that I'm not really sure abt how to mount one. It looks that the one from Benn's which is mounted from the underside and the Selden is mounted on the top. As you have had your rig down maybe you can gice us some advise on which one to buy. I would think that one that is mounted on the top is the one to go for?
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Posted By: shaukaas
Date Posted: 09 March 2011 at 12:31
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I doubt there is any room for a whip mounted on the top, unless you plan for a "re-arrangement" for the equipment up there... I'm planning to machine a POM shieve for my Lopolight, so that the whip can be held in place by the four bolts on this one + an additional bolt at the rear. The windex is to be mounted on top of the Lopolight (using a special windex top on the lopolight itself, also using the white rear sector to lit up the windex when its dark.) The VHF antenna is mounted on the side of the masthead, with a suitable bracket. My mast is currently off the boat, but I haven't spent any time looking into this yet. But for next week I've got plans... I also got some inspiration from this: http://www.epoxyworks.com/23/pdf/03-Lost_foam.pdf">Epoxyworks.  Won't happen until next year anyway, as I would need to get some hands-on experience on this. The first epoxy/glassfiber molding project would be an instrument box to be mounted on the coach roof, under the sprayhood. (For 4xIS20 Instruments) Then a box for the Yanmar panel. I will then move on to a some shelves for the interior, as there are enormous amounts of "confined spaces" in the 320 - perfect for fitting in a few more shelves and lockers. (I'm currently working on isolating all the heater hoses for the Eberspächer - a project "from hell!"  )I'm also thinking about moving all the batteries from the port side bench, to the empty section just behind the engine compartment. This would also make it possible to establish some kind of ventilation to get rid of the gas being generated from my open lead-acid batteries, which I intend to keep. (Will replace these by 6V traction batteries when they're exhausted...) -> Reason: The boat is not very well balanced. Too many plans? Need a bigger boat!  ------------- S/Y Nadun - Hanse 320#171 LG3600 - NOR13510 |
Posted By: Tricky
Date Posted: 09 March 2011 at 19:17
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I am looking at the exact same thing my self, have you checked out the dyneema backstay from Benns?
Brg Tricky ------------- Believe Nothing Trust No One Do It Your Self |
Posted By: shaukaas
Date Posted: 10 March 2011 at 12:55
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I have only checked out their webpage, not how the actual product looks like. As I live in the west of Norway, and Benns are located in Sweden, it's too far to travel just to have a look... However, one of my colleagues sailing an Albin Express, has great experience buying equipment from Benns.se webshop. Are anyone aware of an excellent webshop in the US selling Sparcraft spars? ------------- S/Y Nadun - Hanse 320#171 LG3600 - NOR13510 |
Posted By: Rubato
Date Posted: 10 March 2011 at 16:52
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Shaukaas,
Sparcraft US is a disaster, I had much better service going to Sparcraft France directly (I'm in Canada). Having said that, if you're lucky enough to know exactly what you want/need (part numbers) and if you're lucky enough for Sparcraft US to have it in stock then you'll be successful. I have the contact information for a dealer of theirs in the Seattle area if you like.
Steve
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Posted By: shaukaas
Date Posted: 11 March 2011 at 08:48
If anyone have a partnumber for an original Sparcraft whip, similar to Seldén's, I would be happy to get some info!  The reason for me to go webshopping in the US is mainly the prices. Half of Norway, or less - in most cases. Another thing is the enourmous selection of gear, that you won't find in a typical Norwegian boat chandler. There are some rare exceptions, though. But not for sailboat hardware or marine electronics... (But fruit is cheaper in Norway than Wal-Mart. Something I find hard to understand. But I guess Wal-Mart is more into pre-made stuff possible to keep in their stores for a few months, and don't give a damn if the food they sell is healthy or not... )Steve - any webpage or address for your Canadian dealer? ------------- S/Y Nadun - Hanse 320#171 LG3600 - NOR13510 |
Posted By: Rubato
Date Posted: 11 March 2011 at 21:29
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Try Kent, his email is kentp@yachtmastersnw.com
He's connected with Sound Rigging and Yacht Services who are a Sparcraft distributor out of Seattle, Washington, USA
Steve
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Posted By: shaukaas
Date Posted: 14 March 2011 at 20:55
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Ok, what Kent proposed - whas a couple of Seldén whips... So I'm probably going for a custom made, or 3rd party solution...  ------------- S/Y Nadun - Hanse 320#171 LG3600 - NOR13510 |
Posted By: Rubato
Date Posted: 15 March 2011 at 16:12
| Out of curiousity, why don't you want to go with the Selden solution? |
Posted By: shaukaas
Date Posted: 15 March 2011 at 22:38
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I would then have to re-attach everything that is already in place on the masthead - and possibly modify a few things to get it all back in place... BUT: By modifying the POM shieve/base for the Lopolight, I might be able to use this as a "base" - and use it's three M6 or M8 bolts to keep the whip in place. If I just knew ALL the details... ------------- S/Y Nadun - Hanse 320#171 LG3600 - NOR13510 |