Adrian Evans
Posted on Friday, June 22, 2007 - 12:19 pm:
Martin, I seem to remember on the old forum that you posted about some modifications you had made for sea sailing - strengthening under the tabernacle, as I remember?
When you've a moment, I would be grateful if you could recap on the reasons and the particular measures you have taken. In due course, the West coast of Scotland is in my sights for cruising, and Peggoty may get an outing to Gigha fairly soon.
Martin Cartwrght
Posted on Friday, June 22, 2007 - 01:53 pm:
Firstly, congratulations on your new purchase!
The installation of a post under the mast from hull to underside of coachroof came about through a combination of factors:-
1. I felt that the coach roof flexed unnearvingly anyway when the mast went up and there was evidence of the beginnings of a stress fracture on the deck.
2. I did not like the thought that if the bowsprit failed the mast would come down
and I wanted the flexibility/safety/power of a staysail. By fixing the tack to the stempost it provided a secondary mast support.
4. I did not like having only one shroud each side, as failure would result in a lost mast.So I doubled up, which also helped with the increased load of the extra sail area.
5. 2-4 above added to the downward pressure of the mast on the coachroof which I already felt was a weak point, hence the installation of the post.
6. I have beefed up the ropes and blocks over a period of time, really for ease of handling rather than strength.I also prefer bottle screws on the shrouds rather than rope (to the horror of the purists!).
7. My second set of shrouds are secured by a bronze mastband which also takes the staysail halyard block and mainsail gaff halyard block, thereby reducing the number of blocks at the top of the mast (reducing stain on mast).
8. Finally! The stainless gallows which support the mast when lowered were deck mounted and unsurprisingly there was evidence of stress fractures in the fibreglass. I replaced these with stainless tube which goes through the deck to the hull and I have recently had these welded to a stainless rail for helmsman back support and cockpit safety.
Martin Cartwright
Posted on Friday, June 22, 2007 - 01:54 pm:
Sorry. 7 should read '(reducing strain on mast)'.
Adrian Evans
Posted on Thursday, June 28, 2007 - 06:27 pm:
Martin. thanks for this. I've only just got to reading it after readying Peggoty for her first outing. I like the idea of a stay sail very much, and can see the sense in the beefed up rigging. My problem would be that I need the full V berth, and so the post would get in the way. it would be possible to fit a beam under the mast spanning gunwhale to gunwhale, with a bearer aloNg each gunwhale to spread the load, but that is starting to be quite an undertaking.
I suppo
Adrian Evans
Posted on Thursday, June 28, 2007 - 06:33 pm:
in my last message, 'whistle post' should read 'why the post'.
errant hand writing recognition on my gadget...
Martin Cartwright
Posted on Friday, June 29, 2007 - 09:42 am:
I agree that the beam idea is a bit drastic. I used a removable adjustable chrome table leg (B&Q) for some years, until I realised I never needed to remove it, so I replace it with a permanent steel fitting.(Also I broke one or two - which gives you some idea of the downward forces).
Jeff Wattley
Posted on Sunday, September 02, 2007 - 08:54 pm:
Hello Martin
I am interested in fitting a second set of shrouds and I would be very interested if you have an photos of the position of the new pair of chainplates (and source of them) and also of the mastband. And finally any further details of the post under the mast.
I have recently undertaken my first coastal passage (Helford to Falmouth) and I felt insecure about the strength of the mast in strong gusts.
How tight do you tension the shrouds now that you use bottlescrews (as I do?).
Many thanks
Jeff Wattley
Roger Parish
Posted on Monday, September 03, 2007 - 07:39 pm:
I am surprised to see discussion about shroud tensioning? Surely this is racing boat speak? Shroud and forestay tension is all about inducing mast bend! I put just sufficient tension on my forestay to ensure that the roller reefing works Ok. If you over tension then its not suprising you have to strut the mast.
nickjones49
Posted on Monday, September 03, 2007 - 09:31 pm:
Given my mast and tabernacle are off a converted lifeboat, I'm pleased to have a timber post to keep things apart.
'Puffin' is featured on her summer holiday in Salcolme as a recent entry in the WB Gallery
Nick Jones
Julian Swindell
Username: Julian_swindell
Registered: 03-2007
Posted on Monday, September 03, 2007 - 09:34 pm:
I think I would agree with Roger on this. I make sure that the lanyards are nice and firm and leave it at that. If they seem at all loose I tighten the forestay a bit. When I am sailing in a stongish wind, the lee shroud always goes loose, but so long as the weather one is taught and holding the mast in place, I feel comfortable. I think the risk of a mast being blown over in such a low gaff rig is pretty remote. The lean of the boat will spill most of the wind before that. I would be much more concerned about over-tensioning bottle screws. This is not a high powered boat.
Martin Cartwright
Posted on Tuesday, September 04, 2007 - 09:13 am:
Hi Jeff. I agree with Roger and Julian. No tensioning is necessary. The reason I have bottle screws is the same as why I have a second set of shrouds - for reassurance when sailing solo at sea. It is unlikely to be wind strength which causes shroud failure. I feel that wear and tear is more likely (especially with stainless shrouds and the mast going up and down every trip), and having double the shrouds would half the probability.I will post some photos in due course.
Jeff Wattley
Posted on Wednesday, September 05, 2007 - 07:06 pm:
Very many thanks to you all. The area I am seeking to protect is the tabernacle which now creaks a good deal less than it used to before I tightened things up a bit. I'm not talking about creating any kind of active tension, but I am talking about reducing the slack in both shrouds when the mast is upright. The lee shroud still becomes loose when there is a decent blow.
Thanks. And Martin, I will appreciete the photos when you find time.
Many thanks again, Jeff Wattley
Julian Swindell
Username: Julian_swindell
Registered: 03-2007
Posted on Wednesday, September 05, 2007 - 10:24 pm:
Jeff,
in my experience on boats with lanyard lashed shrouds (I sailed a Drascombe Dabber for 13 years before the WB), the lee shroud always goes loose, even in a gentle blow. If you have it set up so tightly that it doesn't, you will ram the mast down through the hull eventually. Both shrouds need to be tight when the boat is at rest, but the windward lanyard will always stretch under load and let the mast bend a bit.
martin cartwright
Posted on Friday, September 07, 2007 - 07:38 am:
Hi Jeff.
1. Additional Chainplates:- Using the original as a template, I had 4 new stainless ones made up at the local marina. I positioned the new ones just aft of the mast, so they are about 440mm apart.
martin cartwright
Posted on Friday, September 07, 2007 - 07:53 am:
2.Mastband :- Bronze from Classic Marine Woodbridge. I fitted mine 770mm (centres) down from the masthead fitting and attach the staysail to the front, shrouds to the sides and the mainsail throat halyard to the back.
Martin Cartwright
Posted on Friday, September 07, 2007 - 12:16 pm:
3. Mast strut:- I used a 100mm square section post to go through the fore peek ply (and foam underneath)to take the load through to the hull. This ends flush with the ply and I used a steel tube (with a flange top and bottom)as the strut. I wrapped this with rope to make it softer and look better.
Martin Cartwright
Posted on Friday, September 07, 2007 - 01:12 pm:
Staysail:- As I mentioned previously I have this as a 'belt and braces' measure. If I ever lost the forestay it would hold the mast up. It doesn't add to speed, but I think it adds to power when sailing into a sea.
Martin Cartwright
Posted on Friday, September 07, 2007 - 01:28 pm:
Finally! I really can recommend the pushpit and chart table modifications. The former adds considerable strength (particularly with the mizzen)and is great to lean on long passages (and hang onto if you are either inside or outside the boat )and the latter is a bit of fun, but provides a useful space to keep paperwork dry as long as you dont need to go below in a hurry.
Jeff Wattley
Posted on Friday, February 15, 2008 - 10:04 pm:
Hello Martin
Thank you so much for the immensely helpful information you posted about strengthening your Winkle for sea sailing. For various reasons I have not been able to think about my boat for 3 months but I am now getting back into the game. In fact I have just repaired a cracked tabernacle. The pictures were excellent and the information about how you sourced the parts was very valuable. I shall be thinking about this carefully.
Thanks Jeff