Mast rigging tuning for 57 instructions
Dear Professor,
Is there a mast tuning instruction for the 57 sloop?
I ask as we have sailed 40,000+ miles and while in NZ completely re-rigged the original mast with all new rod rigging from the chainplates up, including a new R4 furler.

As in our previous re-rig, we preserved all the original lengths, and then followed the normal routine, centre the mast tip via tighten the V1's, tighten the D2's with tightening the forward lowers finishing with the aft lowers to a reasonable tension along with the mast collar rubbers.

Now we have in some conditions, mostly at dock or anchor, where the wind is able to make the mast 'pump' slightly but noticably. This was never the case before, and now even setting the staysail stay and runners and pumping the backstay to 2000 does not stop it. The riggers here in OZ wish to increase the tension considerably above what has been 'normal' before.

This worries me, as I do not wish the mast/fittings to fatigue, and prompts my question of more precise tuning/preload instructions, since as you know there is no mast jack.
Any help, manual or advice is greatly appreciated!
Best regards and thank you for your very informative informations here.

Robert Ahbel - Concerto 57/022

Dear Robert
Thank you for your message.
I would suggest that increasing the tension in the rig is not an effective remedy.
On every sailing yacht Von Karman vortices develop behind the mast when the wind blows, and if the resonance conditions are right the consequence is vibration as described. This occurs on very few yachts, however.
As you did not have vibration before something has now changed, and my suggestion is to check the mast rubber wedge area. For example by wedging the mast firmly into the collar with wooden wedges each side you will immediately see if things change.
Mast rubber installation instructions can be found on this website, http://www.classicswan.org/file/maintenance-manual/2009_12_28_17_42_53-mast.jpg
Would appreciate to hear if you eliminated the vibration

I do not know what you consider "normal" pretension - are the leeward shrouds going slack on the wind?
Kind regards
Lars

Dear Lars,
Thanks for your comments, and no, the leeward shrouds do not ever go slack.

Are there any instructions for rig set up for 57?

Rig tension, for lack of instructions, has been set up as previously described and V1's are tightened with well lubricated threads with 24" long wrenches until
I can not tighten more. I then tighten the D2's with 12" wrenches.
The final step has been to heel with spin halyards to each side (this alarms the neighbors!) exactly 10 degrees, and tighten V1's again, which also tightens D2 and D3.
I gain usually 1 to 1 1/2 turns on each side and keeps mast tip centered by doing each side evenly. When sailing with backstay set to 2000 pounds, the mast is smoothly curved just less than 1/2 of the mast dimension fore and aft. Do you think there is
anything wrong with this set-up procedure, or have you suggestions, please?

The mast rubbers, and your suggestion of wooden chocks. Might you clarify please, replace the mast rubbers? By the time the winches are used as per Nautors calculation that came with the boat for the thickness at the deck collar, there is considerable
preload, but these rubbers are now 30 years old. Perhaps this accounts for the change and start of pumping since these were disturbed?

Is there a source for the correct material for new replacements?

Also, off topic, but I have sent a request for new foredeck hatch seals to sales at Nautor, but Tapani Bro answered these are no longer supplied by Nautor,and could not help me
what size these are or a source for them..

Does anyone have the size and shape of the seal material, and a source, please?

I saw a chart of the seals used by Nautor on a previous thread here, but these are samples, but have no size, how stiff, or what application they are used for.

Any help for this would be greatly appreciated, as mine are deteriorated enough that I can not identify them, and even with the fabric hatch cover secured over, the water drip
in during our crossing of the Tasman Sea.

This is a great forum, very informative and friendly people for great boats!

Thank you Lars for your considered response! (and thank you anyone else who has good information)
Smooth seas,

Robert Ahbel 'Concerto' 57/022

Dear Robert
Thank you for the information
I would suggest that the level of pre-tension can not be controlled to any degree of accuracy with the described approach, and there is great risk of causing damage to the turnbuckle threads. The original Swan 57 Owner's Manual text contains instructions for the set up, they are by the way the same that you find in the Maintenance Section on this website under Rigging Setting Up, and this is the recommended way. Pls have a look and feel free to ask if you have questions.
What maximum backstay pressure do you use?
Referring to the rubber chocks the intention of my suggestion was to change their stiffness temporarily, for example by inserting wooden wedges each side in order to see if this causes a change in the pumping - it should. The specifications for the rubber is given in connection with the installation instructions, and suitable material should be readily available. You are right that there needs to be considerable preload in the rubbers.
Another way of affecting the pumping is to arrange all halyards so they disturb the air flow around the mast as much as possible. Winding them around it in a spiral shape is most effective but rather impractical.
The hatch seals are of neoprene rubber, but for their shape the help of other owners is needed. Does your hatch drop down when closing?
Kind regards
Lars

Dear Lars,
Maximum backstay pressure = 2500#
Thank you for the clarification for the wooden wedges.
I will look for the rubber sepecification again, but maybe I am suffering from
early 'Boatheimers' and have not found it yet, but will change them just due to age.
We are in Australia currently, and sailing back to NZ shortly. Lovely sailing and
people but availablility here of even simple things a problem and FedEx from USA or
European suppliers routine in both places.
The seal material that is locally available is in the attachment, The flange is
1.5mm, so that leaves about 6mm bulb protruding. Our hatch does drop as it closes.
I have not found anything that is close to the dimensions of the front seal, so if
anyone has a supplier for a product that works, I would be grateful, and compared
to leaks, FedEx is cheap....
thanks again,


Robert Ahbel 'Concerto' 57/022

Robert
If you are interested to know the mast top fall-off with the proposed pre-tension I can work this out, but would need your rod sizes confirmed.
Regards
Lars

Hi Lars,
That would be great! I downloaded the mast/rigging instructions swan from this web site, thank you, and will re-tune the rig.
I have not found the rubber specification you mentioned, I must be going blind, if you happen to know where that is I sure appreciate the link.
V1 - 48
v2 - 30
d3 - 22
fwd lower - 40
aft lower - 30
D2 - 30
forestay - 40
backstay - 30
staysail 3/8" 1-19, runners same
I checked with NZ Rigging, the manufacturer of the turnbuckles, and they guarantee that I can not damage the threads of the turnbuckles of my V1 with a 24" wrench, but still, I will follow your advice.
Thank you again!

Robert

Robert
The important information for the rubber is its hardness, and Shore 40 is recommended. Rod Stephens specified "tan pure gum floating stock rubber" if you can find that.
Thank you for the rod sizes, will get back on this soon.
The turnbuckle guarantee is likely to refer only when brand new with manufacturer lubrication. I find it hard to believe that old ones with dried salt crystals or grit from being dragged along the ground in the threads would be covered.
Kind regards
Lars

Robert
Here the top fall off, to the left with the shrouds hand tight (i.e. no adjustment), to the right with the slack taken out as described in the setting up instructions.
I guess the picture will be shown in small size here, pls give your mail address so I can send you a bigger one.
Best regards
Lars

Hi Lars,
Thank you very much! svconcerto@gmail.com
I had no trouble (find on internet) buying new mast collar rubber Shore 35-45 here in Australia. I slacked off and re-tuned as per the swan directions. There was a considerable difference in how the rubber felt, and so far, the mast has not pumped again in conditions where it might have.
The only other change is I may have been a little under tightened on D2's, as I am now 1/2 turn tighter, and they feel correct (settling in on the NZ-Oz voyage, perhaps?)
Problem cured I believe, thanking you very very much!!
Now if I could just find a source for the fordeck hatch rubber seal, it would be wonderful...
thanks again, and smooth seas,
Robert
By the way, no dragging our rigging in the dirt. We x-rayed the chainplates and keel bolts. We had the new rod rigging hand polished with 320 wet all the way up to 1200 wet paper by us inspecting it on carpet on the dock, and rejected two pieces of rod when defects were revealed via this method. To their credit, KZ Marine made us new replacements at no cost, and even loaned us their truck to take them to the boat. It turned out the defects were worse further along in the roll, and we were just 'lucky' to have the first ones found, not while sailing.