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Oliver Shaw
ModeratorSeveral points here; and by coincidence a post has appeared on the GP14 Owners Online Community forum more or less simultaneously asking for advice on binning the wire+rope halliard and going to rope only!
In part, a great deal depends on the type of sailing you wish to do. If you can be quite certain that you will never, ever, need to reef the boat then there is a very slight benefit in using a wire halliard; although dyneema is very nearly as good, and even pre-stretched polyester is quite good enough for most purposes – but it absolutely must be the pre-stretched type. Non-prestretched polyester has almost as much stretch as nylon.
If you are ever likely to reef the sail you absolutely must not use a combined rope+wire halliard, because once the sail is reefed the halliard is now in a different position, and that then places the full halliard tension on the wire to rope joint. However that joint is made this is an unfair load, and doubly so if the joint is a simple eye splice in the rope interlocking with an eye splice in the wire, which is usual in the class; the wire then tends to act as a (blunt) knife, and in time will cut through the rope. It is simply not designed for this use, only for use while you are in the process of hoisting or lowering the sail.
On the matter of reefing methods, see my paper on Reefing Systems in the Members’ Library on this site.
As a very broad generalisation, if absolutely all your sailing is to be racing you will probably be very marginally better with a wire halliard; and since races are won or lost on marginal factors this could be important – once your sailing skills are good enough! However if you intend to do any cruising at all, including just day-cruising, the ability to reef the boat becomes potentially important – indeed it is potentially life-saving if you get caught out; so if any sort of non-racing sailing figures in your intentions then stick with all-rope for the main halliard and also equip the boat with the means of reefing. Incidentally the rig as originally designed (in 1949) incorporated a means of reefing, square gooseneck roller reefing, but most modern GP14s have ditched that arrangement; most boats used for high level racing are never reefed, and are not able to do so, and most serious cruising boats are nowadays equipped with slab/jiffy reefing, which is a more modern and very much better system than the original.
You hit the nail on the head in picking up that the genoa has a better means of adjustment, and (more importantly) a means of achieving far greater tension, than does the main. That is absolutely correct, and there are two reasons for it.
First, as well as serving as a means of hoisting the sail the genoa halliard also stresses the entire rig, in particular it tensions the shrouds (and produces compressive loads in the mast and the spreaders and potentially also the mast gate), and thus helps to control the amount of bend in the mast; second, it also serves to keep the luff of the genoa reasonably straight, preventing it sagging away too far to leeward. For both reasons the genoa halliard tension needs to be quite high, and at the top level of racing it also needs to be adjustable to suit the wind strength.
With the mainsail the situation is very different. The shape of the luff is controlled by the mast, and modern masts are designed to bend, with the amount of bend being controlled by (primarily) a combination of the rig tension (set by the genoa halliard) and the kicker tension, with a smaller influence when going to windward also provided by the mainsheet. Mainsail luff tension plays no part in controlling the mast bend, and main halliard tension has no effect on the rest of the rig.
It is of course important to have sufficient mainsail luff tension to remove horizontal creases from the sail, but the tension needed to achieve that is comparatively modest, certainly very much less than the genoa halliard tension. The normal technique for setting the mainsail luff tension is to hoist the sail until the head is up to but not beyond (the bottom of) the upper black band, and then secure the halliard. Then, and only then, pull the boom down to (the top of) the lower black band. If you have a sliding gooseneck you can put the boom onto the gooseneck first and perform this adjustment by means of the slide, but most modern GP14s have fixed goosenecks, in which case you don’t put the boom on the gooseneck until after you have hoisted the sail and secured the halliard; then you pull the boom down onto the gooseneck.
If you attempt to hoist the sail with the boom already on the gooseneck (if fixed), or already at the lower mark (if using a sliding gooseneck) you will not succeed in getting sufficient luff tension; but provided you hoist first and adjust the luff tension second it is quite easy, and your own weight does the job.
Once the main sail is correctly hoisted and set there is unlikely to be any need to adjust the main halliard except, perhaps, to ease it off a little in ghosting conditions. However in stronger winds if your sail has a Cunningham fitting, and most modern racing sails will have, you may wish to tension that when going to windward in order to move the fullness of the sail forward.
Finally, a lateral comment on one point in your post; never underestimate the size and power of that genoa; it is a seriously big sail. In a decent blow it will pull like a train, especially when going to windward; and in strong winds it has enough area to potentially capsize the boat on its own – be warned! And while we are talking about the genoa, a GP14 will sail surprisingly well under genoa alone on any point of sailing, even beating to windward if needed; just occasionally it is useful to know that the boat is capable of doing that.
If you eventually decide to specialise in racing, once you reach Gold Fleet standard – if you become that good – you may then wish to modify this advice; but I am sure it is sound advice for your present level of skill, as someone new to the sport, and quite probably for a long time forward into the future as well.
Hope this helps,
Oliver
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This reply was modified 7 years, 8 months ago by
Oliver Shaw.
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This reply was modified 7 years, 8 months ago by
Oliver Shaw.
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This reply was modified 7 years, 8 months ago by
Oliver Shaw.
Oliver Shaw
ModeratorWell done.
I envy you your mast-length workbench! Almost designed for the job!
Two of the photos suggest that you might have had a past problem of woodworm infestation. If so, you will of course need to treat it before glueing the mast back together.
Oliver
Oliver Shaw
ModeratorInterprotect data sheet:
Website here – https://international-yachtpaint.com/en/gb/
Datasheet here – https://s3-eu-west-1.amazonaws.com/akzonobel-live/documents/TDS/Interprotect_eng_A4_20180129.pdf?mtime=20180222011126
It would seem from the data sheet that you can apply it at temperatures as low as 5 deg. C, although I think it would be worth talking to their Helpline first: 01489 775062 , or email iyp.uk@akzonobel.com.
Hope this helps,
Oliver
Oliver Shaw
ModeratorI am sure that I have also heard that fumes from a paraffin heater will affect the cure of epoxy, and for that matter of many paints. And certainly I would expect that to be the case.
Pity!
If it is any consolation, I am also held up with a major GRP repair on the (small) yacht, for exactly the same reason …
If you refer back to my reply on 6th January you will see that I said the headline epoxy product is WEST System epoxy, but I also suggested that as a sealant it might alternatively be worth considering International’s Interprotect. I don’t personally know that product, I merely know of its existence; but it might be easier to apply (i.e. it might flow out more easily), and it just might be more tolerant of lower temperatures. At least it would be worth looking at the data sheet, and perhaps phoning their Helpline to discuss it with them.
Oliver
Oliver Shaw
ModeratorI most warmly approve of the principle of through bolting the hounds band, even though I agree that in this instance the job has not been done particularly neatly. I strongly recommend that you retain the principle, but by all means replace that bolt by a stainless steel one, with stainless nut and washers, and cut off the surplus length.
As with all fittings, use sealant around all fastenings, to ensure that you don’t get rain water penetrating into the wood. Clear silicone sealant is adequate, and it is readily obtainable, although there is an argument that polysulphide is better, and it is about the same price, but it may be less easy to obtain.
Quite early in my sailing career I raced Fireflies at university, and we regularly broke masts as a result of shroud failure. When I became Maintenance Officer of the college sailing club I took it upon myself to address this issue, which I did with some success; however I myself broke one of the masts while racing in the Nationals in about 1963 or ’64. and that experience stood me in good stead after I left university and moved to GP14s. Within my first 4 years, or thereabouts, in GP14s I suffered three shroud failures, but because I had already had this experience in the Firefly I reacted instantly when I heard the loud bangs, and so on each occasion I was able to save the mast. Thereafter I learned my lesson regarding rig maintenance, and in the fifty years since I have never had another shroud failure …
The last of those occasions taught me the value of through bolting the hounds band, the fitting that you are referring to. Two of us were sailing my GP14 on Ullswater, a gloriously scenic lake in the English Lake District, perhaps 8 miles long. We had enjoyed a superb downwind sail the full length of the lake, and we were now about two-thirds of the 8-mile beat back home to our launching point at the head of the lake. We were both fit and enthusiastic sailors in, then, our early twenties, so the physical exertion of the beat did not worry us, and in perhaps force 5 we were sitting the boat out hard.
Suddenly there was the tell-tale loud bang, so we reacted instantly; tiller down hard and tack the boat. No time for any preamble to the tack, or any warning, and the time for looking around to check whether anything was in the way was only after we had already initiated the tack. As we went through the wind I spotted that the lee shroud had also gone slack; the problem was not that the weather shroud had broken, but that the hounds band had pulled off the mast!
We immediately therefore aborted the tack, and ended up sitting in the middle of the boat, head to wind; we then dropped all sail, broke out the oars, and rowed the rest of the way back to our launch point.
After I got home I not merely refitted the hounds band, but drilled it and inserted a through bolt. Just like your one!
Since then, on each of the small handful of boats which I have owned with wooden masts, including my present yacht, the hounds bands have all been through bolted!
However there are a couple of things that you could usefully do, given that you are repairing the mast anyway:
- Check the state of the wood where the bolt passes through. If that is crushed or damaged, consider whether you need to insert a small piece of new wood to provide a new bearing surface. Possibly even insert it with the grain horizontal, to give the strongest bearing surface against the bolt, and make it diamond shaped to give the strongest glued bond with the vertical grain of the mast; another option, if you have access to a suitably large plug cutter tool, is circular, but still with the grain horizontal. Bond it with epoxy, of course.
- While you are doing the job, once you have completed all the repairs strip off all the old varnish back to bare wood, and start again. Use a nice pale varnish, to achieve a pale golden colour to show off your (white) softwood spar to best advantage; it is probably either spruce or Douglas Fir, and it can look stunning, but it should be much lighter in colour than your one is at present.
Enjoy your project. There is a bit of work to be done there, but the result should be very satisfying.
Oliver
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This reply was modified 7 years, 9 months ago by
Oliver Shaw.
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This reply was modified 7 years, 9 months ago by
Oliver Shaw.
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This reply was modified 7 years, 9 months ago by
Oliver Shaw.
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This reply was modified 7 years, 9 months ago by
Oliver Shaw.
Oliver Shaw
ModeratorDon’t rule out the potential calibre of the earlier boats. Famously, David Warden-Owen won the 1970 National Championship in Gwladys Too, no. 830; I don’t know her precise age, but certainly pre-1956.
And a few years ago we held a Vintage Regatta on Bassenthwaite, coinciding with the End of Season Championship, and with the same start and sailed over the same course, just one lap fewer for the vintage boats. Steve Parry campaigned his “modernised vintage boat”, i.e. a vintage hull with modern rig, Stewart Elder campaigned Aeolian, no. 28, and Kev Foote and I campaigned the newly restored (and still entirely untuned) Caltha, no. 47, on her first time out. If memory serves correctly, both Aeolian and Caltha were wearing original rig, albeit in Dacron rather than cotton sails, i.e. wooden masts and booms, no spinnakers, and standard (i.e. small) jib rather than genoas. And although these vintage boats were clearly never going to be a match for the boats at the front of the Championship fleet, all three boats were ahead of the tail-enders, notwithstanding the latters’ genoas and spinnakers.
Oliver
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This reply was modified 7 years, 10 months ago by
Oliver Shaw.
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This reply was modified 7 years, 10 months ago by
Oliver Shaw.
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This reply was modified 7 years, 10 months ago by
Oliver Shaw.
Oliver Shaw
ModeratorSeconded.
And this amply shows that plastic, whether GRP or FRP or epoxy, is not the universal panacea that removes all need for maintenance of a boat. Plastic boats, in whatever plastic material, can still have significant problems which need sorting out.
And when it comes to ease of repair, I suspect that overall there is less difference between wood and plastic than many boat owners imagine; it is not that plastic is significantly easier, simply that the techniques are different. Says he with feeling, having been stalled for the last month over a significant and important structural repair on the big boat (well, slightly bigger), which is indeed GRP, simply because if I attempt the repair at these low temperatures I can’t rely on the structural strength of the epoxy. I can’t safely do anything further on the repair until the weather warms up significantly; the risk is that a possible subsequent failure could be life threatening if it were to happen at sea.
Oliver
Oliver Shaw
ModeratorA little bit of history, and further explanation, for you.
Chris notes that builders (choose to) make boats slightly underweight in order to obtain the best racing performance, and then add corrector weights to bring them into class. Historically that has long been the case, but in recent years an additional and larger factor has come into play.
The origin of the particular figure for the minimum weight is that this was a (standardised) weight, close to that at which a newly built wooden GP14 would naturally come out if well built, using top quality materials.
By 2009/10, at which time I was serving on committee, David Rowlands made us aware that the natural build weight for new boats, both wooden and plastic, had reduced as a result of changes in materials used. In the case of plastic boats it was due to the switch from polyester to epoxy resin, which naturally produced a lighter boat even though at the same time it was also stronger than its polyester predecessor. In the case of wooden boats it was because of the near total disappearance from the market of the older traditional boatbuilding woods, resulting in builders having to switch to alternative woods, which happened to be less dense.
David advised us that in both types of construction, builders were then adding additional material, structurally unnecessary, for the sole purpose of bringing the finished build weight up to specification. Depending on precisely where this material was added it could affect one or more of the boat’s principal moments of inertia, three physical properties which control how rapidly the boat will turn and pitch and roll, and he advised that this could conceivably give a competitive advantage to particular solutions to this problem. On David’s advice, committee therefore wished to control where and how this additional weight was to be added, and in particular we wanted to achieve this in such a way as to have a neutral effect (so far as reasonably possible) on the moments of inertia. The result was the introduction of “Association Corrector Weights”, additional to the weights secured to the underside of the thwart, to bring the build weight (as distinct from the sailing weight) up to specification.
David did the overall design for this project, and I did the underlying maths for it.
I can date the conclusion of this project to the precise year, 2010, because that was the 60th anniversary year of the class, and as part of those celebrations the Association were exhibiting two of my boats (A Capella, a then fairly new and well equipped dedicated cruising boat, and Snowgoose, a vintage boat from 1951, the first year of the Class) at the RYA Dinghy Show. And it was while we were both on the stand at that show that David and I went through my mathematical analysis, which he then used in finalising his design.
Oliver
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This reply was modified 7 years, 11 months ago by
Oliver Shaw.
Oliver Shaw
ModeratorIf you are intending to fit an additional access hatch you may wish to consider fitting a seriously large one, ideally one each side.
The ones I had fitted to A Capella, as per the attached photo, were almost 1 foot in diameter. That gives vastly better access, and better ventilation, and additionally (for cruising) it enables you to use the tank for stowage of light but bulky items which would otherwise be aboard the boat anyway; probably not an issue for racing, but I stowed my inflatable fenders in there.
Expensive, but perhaps worth considering. I see that Force 4 are currently listing some very similar non-lockable ones by Bomar.
Oliver
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This reply was modified 7 years, 11 months ago by
Oliver Shaw.
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This reply was modified 7 years, 11 months ago by
Oliver Shaw.
Attachments:
You must be logged in to view attached files.Oliver Shaw
ModeratorOh dear!
My impression is that all professionally built GP14s built in recent years are fully coated in epoxy inside and out during the build process, and most certainly that was my clear understanding from my builder (Tim Harper) when he built A Capella for me in 2005/6.
Of course amateur built boats may not necessarily be to the same standard; that all depends on the individual builder, but I also have the impression that amateur built boats form only a tiny minority of the modern ones, and especially so since Fyne Boats dropped the GP14 kits from their range some years ago.
This suggests that perhaps your boat may be significantly older than you had thought, or alternatively that she is one of the comparatively few amateur built ones. Do you have her registered hull number? (On a Series 2 boat look on the aft face of the centreboard case, just above the cockpit sole.) Do you know who the builder was? (Assuming she is registered with the Class Association, her original measurement form should be on file, and it should show the name of the builder.)
Either way, the problem is what to do now. Most certainly I would recommend sealing all the hidden surfaces of the wood. If you can get the wood properly dry and clean, consider using epoxy as a sealant; the headline product is WEST epoxy (or similar), but that may be difficult to apply retrospectively inside the buoyancy tank, not least because of limited access – that may make it extremely difficult to get back to clean wood, and may also make it difficult to apply the epoxy right into the corners and crevices. If you do go with WEST (or similar) epoxy despite the difficulty of access, consider warming both the wood and the epoxy to achieve easy flow, but use the slow hardener to still allow you reasonable working time at the warmer temperature.
It is possible that Interprotect (an epoxy polyamide primer by International Paints) may be easier; that is not a product that I myself have ever used, but I have considered it from time to time, and certainly it is worth a call to their Technical Helpline to discuss it with them.
If you feel that the restricted access makes it difficult to do the job adequately with epoxy, than a good quality bilge paint (e.g. Danboline) would seem to be a good fall-back option.
Finally, when you are ready to revarnish, I would recommend using a minimum of 6 coats on top of your epoxy. No point in spoiling the ship for a ha’p’worth of tar.
Hope this helps,
Oliver
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This reply was modified 7 years, 11 months ago by
Oliver Shaw.
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This reply was modified 7 years, 11 months ago by
Oliver Shaw.
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This reply was modified 7 years, 11 months ago by
Oliver Shaw.
Oliver Shaw
ModeratorWell that’s a bit of good news for you. Glad you have been able to get it sorted out.
Oliver
Oliver Shaw
ModeratorExcellent, and I am delighted that my guessed identification has proved correct.
I am reasonably sure that this is not merely a build number, but the registered hull number; but do check that point with the Association. Now that you have this data you have a positive identification, and can ask the Association for our digitised records of her. And you can indeed re-register her with the Association.
Why would anyone paint over a maker’s plate? – It happens all too often, and not only with boats. Usually because whoever did the paint job did not appreciate, or have any personal interest in, the data in question; and simply could not be bothered to either paint round it or mask it off. Yes, I know; Philistines! …
Oliver
Oliver Shaw
ModeratorRemoving paint from the identification plate: I don’t know of any fully reliable method, but with the corresponding problem on my bigger boat I had some success with very careful use of paint stripper.
Apply it, and leave it the bare minimum of time to soak in – err on the side of too short rather than too long – and then remove it as gently as possible, so that you remove ideally just the top layer. Then repeat as necessary, removing just a little at a time.
Ideally choose one of the more gentle paint strippers, and if you are buying specially I would read the instructions to see what jobs they are formulated for; some are specifically formulated for the more easily damaged substrates, at the expense of being less powerful at stripping the paint. Perhaps use steel wool, used gently, to remove it, rather than a scraper. Wear protective gloves!
Good luck.
Oliver
Oliver Shaw
ModeratorThanks for that sketch. Is it possible, at your convenience, to obtain one or more photos of the deck support brackets?
There is a Mark II boat which I am fairly sure is by Bourne Plastics on eBay at the moment; item no. 152793983682. If you have a look at her I am sure you see the differences from your boat in the way of those deck support brackets, the mounting of the side benches (on raised GRP in your boat, but on mahogany spacers in the Bourne Plastics boat), and the capping of the centreboard case (immediately ahead of and abaft the thwart). However this boat does have the stainless steel thumb screw friction adjuster for the centreboard, which I had thought (perhaps wrongly, after all I am really a wooden boats man …) was primarily associated with Thames Marine rather than Bourne Plastics.
Oliver
Oliver Shaw
ModeratorThanks for coming in on this, Stewart, but unfortunately it seems that the sail number is incorrect. The boat appears to be a Mk 2, which seems to date her as not later than 1977, but sail number 12493 was issued in 1983.
We hope he can trace either a registered hull number or a moulder’s number (and moulder’s name), which would enable a positive identification.
Oliver
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This reply was modified 7 years, 8 months ago by
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