Forum Replies Created
-
AuthorPosts
-
Oliver Shaw
ModeratorNot sure; can you supply a photo, please.
Oliver
Oliver Shaw
ModeratorExcellent!
Oliver
Oliver Shaw
ModeratorSteve,
In an idle moment I looked at your profile, and spotted the name of the boat. That name rang a bell; and coupled with a sail number around 9000, and the Series 1 to 2 conversion – which is quite rare, and based in the northwest, I think I know the boat. Did you buy her from Peter Johnson, a member of Liverpool Sailing Club?
That is my home club, and when Peter was considering buying her I vetted the boat for him!
Peter had joined the club a short while earlier, declaring that he wanted to try out a number of different boats until he had decided which class to buy. I took him out just once in A Capella, and he was so delighted with her that he immediately declared that his search was ended; his choice was a GP14. I didn’t attempt to persuade him to try others, because I am an enthusiast for the GP14 myself.
Regards,
Oliver
Oliver Shaw
ModeratorThe differences in likely shank diameters, i.e. 12 or 13 mm, or 1/2 inch (= 12.7 mm) can be significant.
Although in deference to age (81) I have reluctantly retired from GP14s, and have very happily passed A Capella over to my godson as an advance on his future inheritance, I have recently refitted her for him. After revarnishing the decks and replacing the fittings the starboard rowlock was fine, but the port one was very stiff. The obvious solution, in default of a reamer, was to re-drill the hole for the shank.
I tried a 12 mm (metal) drill, but it went in far too easily, and achieved nothing. I then tried a 13 mm drill, but that would not pass through the hole in the socket plate. However I am of an age to still have some pre-metric tools, so I then tried a 1/2-inch drill, and it did the job to perfection. A Capella‘s rowlocks, bought new in 2006, very much in the metric era, clearly have 1/2-inch (i.e. non/metric Imperial size) shanks. Of course, I could have saved myself a couple of trials had I bothered to get out the micrometer, or the verniers, and actually measure the shank … …
Oliver
Oliver Shaw
ModeratorIf you ask Tim to fit the plates he will of course do the reinforcing.
It is not a job that I have ever done myself, but it is one that I would have been perfectly happy to do. (Tim fitted the socket plates on A Capella, since this was part of the build). Sitting at home in my armchair(!) I would expect to do the following:
- Measure up and mark the centres of the holes. Double check these measurements; the old adage is “Measure twice, have a cup of tea, then measure again; then cut once”.
- Offer up a piece of mahogany under the deck, I suggest 3/4 inch to 1 inch thick, very substantially longer and wider than the socket plate, but precise dimensions not critical; bond this in place with epoxy. If underside of deck is bare, or if it is coated with epoxy, the new bond will be strong. If it is merely varnished, the bond will be the (uncertain) strength of the varnish, so err on the large side with your choice of dimensions for the reinforcement. One way to hold the reinforcement in place while the epoxy cures would be to drive a single screw into it from above, screwing exactly through the marked centre; once the epoxy has set you can remove the screw, and when you then drill out the hole all trace of that screw will have been removed. Preferably remove the screw before the epoxy has cured fully hard; but if you misjudge and then find difficulty in getting the screw out a soldering iron applied to the head of the screw should soften the epoxy enough to enable removal.
- The socket plates may have a very short downward protuberance around the hole; to call it a tube would be too grand a term, perhaps between 1/8 and 1/4 inch (3 to 6 mm) deep. If so, using a self-centring wood bit, drill out to that diameter and depth – adding the thickness of the plate to the depth, to enable the socket plate to eventually sit flush, recessed into the deck. If no such protuberance, reverse the order of some of the following steps; drill for the shank first, using a self-centring drill, then match the plate to the drilled hole, using the drill bit as a mandrel for getting the plate in exactly the correct position.
- Insert the plate into that hole (it will of course still be sitting proud of the deck at this stage), line it up accurately fore-and-aft, then use a Stanley knife (craft knife) to mark around the outside. This will probably be a rectangular shape; if you happen to have chosen socket plates of elliptical shape this really is making a lot of extra skilled work for yourself! Take great care to cut exactly along the line of the plate, and not to mark the varnish outside the plate. You can afford to cut into the deck to fractionally more than the thickness of the metal plate. Note that at this stage you have still not cut the hole for the shank of the rowlock; that is left for much later.
- Using a freshly-sharpened wood chisel, remove the necessary depth of plywood from inside the marked region, taking particular care not to damage the deck outside that marked region. It is vitally important that the chisel is really sharp. Initially settle for making the hole very slightly too small; it is easy to open it out further, but impossible to do an invisible repair if you cut too much! Aim to achieve a level bottom to your hole, which will perhaps be about 1 mm deep.
- Using the chisel and the Stanley knife as required, open out the hole until the plate sits neatly inside the hole, and flush with the deck.
- Once you are satisfied with the fitting of the plate, insert the securing screws.
- The shank diameter will typically be either 12 or 13 mm or 1/2-inch (which falls between the two metric sizes). Provided you have access to the correct size of drill bit (which may be a problem if it is 1/2 inch and you have only metric sizes), you can drill through the socket plate, and in that case the bit does not need to be self-centring; either a wood bit or a metal bit will do equally well, as the plate will keep it centred.
- So, with the plate fitted, and screwed down, drill through the hole in the plate for the shank of the rowlock, provided you have the correct drill bit size.
- However, if you find yourself having to drill fractionally larger than the hole in the plate, e.g. 13 mm for a 1/2 inch plate (just 0.3 mm over-size) you will need to take the plate off again, and then you must use a self-centring wood bit; a bit designed for drilling metal will be too prone to wander off the true line.
- Now check the rowlock in the hole, to test for a good fit.
- Finally, with everything fitted, and working, remove the plate again. Varnish the bare wood. Then refit the plate, bedding it down onto your choice of sealant.
Job done!
It actually sounds more than it is; if you are reasonably familiar with quality woodworking the job is not particularly difficult. But accuracy at all stages is the name of the game, and if you are nervous of your abilities then it is a job perhaps better left to a professional.
If you happen to read these posts by email rather than on the website, please be aware that this one has had several edits, so do look up the latest version on the website.
Oliver
-
This reply was modified 1 year, 5 months ago by
Oliver Shaw. Reason: Notification of edits
Oliver Shaw
ModeratorNoting that this is a wooden boat (Series 1, with the series 1 to 2 conversion done), that you say you are nervous of cutting holes, and that you want a good dinghy builder in the north-west, I would recommend Tim Harper, who is based in Southport. He has in his time built some beautiful, and somewhat bespoke, GP14s, including my own A Capella. Last time we met, at a Past Commodores’ Dinner earlier in the year, he gave me the impression that he is now semi-retired, and said that he no longer builds, but still does repairs.
It would be worth determining first where you want the sockets to go; there is a lot of material pertinent to this earlier in this very string.
Then decide on what rowlocks you want. Metal is vastly stronger and more rigid than plastic, so I personally would never have any confidence in plastic ones. Galvanised are el cheapo, and very strong, but a bit “agricultural”; you may feel (as I myself do) that to fit them to a beautiful wooden GP14 would deface the boat.
The strength of Chrome-plated rowlocks depends heavily on the quality of the substrate, which is likely to be either brass or die-cast zinc alloy. I have heard mixed reports, with some owners reporting fractures, and others having had no problem. Indeed there is one adverse report almost immediately preceding this reply in the same string. However it is difficult to compare like with like, as I have no information on particular brands; and even for the adverse reports that I have heard in most cases I cannot recall what the substrates were.
For my money the choice is either stainless steel or bronze (gunmetal). Bronze are probably the easier of the two to obtain, and are normally available from Classic Marine, or other specialist classic chandlers (such as Marinestore.co.uk, or Davey & Co.) Stainless steel may require quite a lot of online searching, but if you can find stainless ones (that you like) they will be amply strong and they will also be a good cosmetic match to the rest of your stainless fittings on the boat.
It would be worth discussing this with Tim before you buy; he may possibly have sources of supply, or he may prefer you to source them and he will then simply fit them for you.
The neatest type of installation is to have the deck plates (sockets) recessed into the deck so that the surface is flush; and that also gives the most comfortable seating if you happen to sit on top of one of the sockets. However if you opt for that you may find that you need to put a short collar on the stem of the rowlocks in order to lift them a little, so that the oar does not scuff your varnished rubbing strake on the pull stroke. I made my collars by buying a short length of stainless steel tubing of suitable diameter (again an internet search will bring up suppliers), and then cutting it to length. The length is not critical; half an inch, or 15 mm would seem a good length to try.
Hope this helps,
Oliver
Oliver Shaw
ModeratorYour query 4: certainly not brass screws, under any circumstances. Over time they will dezincify, and become very weak semi-porous and apparently crystalline copper screws, which are then useless.
(I think this problem may perhaps not have been known at the time the early boats were built; it seems to have emerged in the late fifties and early sixties when brass screws, which had until then been widely used, started failing for this reason. I was at university in the early sixties, racing Fireflies, and we were forever breaking masts when the chainplates pulled off the hull because the screws failed … … Far more is known today about the behaviour of alloys in the marine environment.)
The appropriate choices are either stainless steel or bronze. Bronze screws are more expensive than stainless, but are very appropriate to the age of your boat; however the screws securing the case to the hog are never going to be seen, so there you may as well use stainless as being the cheaper alternative. You may wish to indulge in the luxury of bronze for screws which will be visible, e.g. those securing the case to the thwart, etc. Bronze fastenings (and much else) are available from specialist chandlers such as Classic Marine, or Marinestore.co.uk, or Davey & Co. There may well be others as well, but I have not found them yet!
Your query 3: I suspect that someone has previously done some work on the boat, at some point since she was built. There is no great need for either the floorboard bearers or the frames to be routed into the case, but it is not wrong to do so; historically some professional builders did rout them in, and other professionals did not. The floorboard bearers are not structural, and serve merely to support the floorboards, but the frames are structural, and serve to fix the shape of the hull, and provide lateral strength.
Only one of the actual frames intersects the case; frame 3, which is the frame that also intersects the thwart. Any lateral weakness arising as a result of splitting that frame (because the case cuts across it) would seem to be amply compensated by the very considerable strength of the two quadrilaterals formed on each side of the boat by the two parts of that frame and the case and the thwart, together with the fact that the thwart is a single and very stout piece of timber bridging those two quadrilaterals. I suspect, but cannot confirm, that the cut inner ends of that frame are also glued and screwed to the hog, albeit that this will be either side of the slot, which will therefore at least help to fix the distance between them, further contributing to a rigid structure overall.
By contrast, joining the two cut ends into the sides of the case, however it is done, would seem to be a joint involving end grain at each surface of the joint if traditional woodworking joints are to be used; so that is never going to be a strong joint. A modern epoxy fillet joint – or alternatively a wooden fillet joint (with horizontal grain at 45 degrees, to avoid exposure of any end grain) – would of course be strong, but that is not what we are discussing, and I am not personally aware of any boat which has needed this modification, although I think it very likely that some owners will have done it. However my own assessment is that ample strength would seem to be provided elsewhere.
Frame 2 is immediately ahead of the case, and frame 4 is some little way abaft it; so each of those frames has its own integrity, not compromised by the centreboard case.
So I would not worry about this apparent alteration to the way the boat was built, unless it troubles you cosmetically.
Hope this helps,
Oliver
-
This reply was modified 1 year, 5 months ago by
Oliver Shaw.
Oliver Shaw
ModeratorThickness first; the permitted range of thickness of the board is 13 to 20 mm, so at 19 mm you are close to the maximum allowed, which is good.
As regards the interior space inside the case, you will need at least some slack in order to allow the board to move freely, and to have a reasonable chance of avoiding it jamming. A particular concern is the risk of mud or sand or small stones getting drawn up into the case and causing the board to jam. I happen to have my very early vintage boat in the garage (no. 64, dating from 1951), and I have just measured the interior width of the case at the top (the only place where it is accessible), and found it to be 26 mm, just very slightly wider than your slot (25 mm). Given that the class was originally designed and built to Imperial measurements, rather than metric, those seems to be to be a very sensible pair of dimensions; a gap of 1 inch (25.4 mm) and a permitted board thickness in the range 1/2 inch to 13/16 inch. So my first thought is that this slot width is very probably right.
If you wished to check further you could check against the plans, available from the office. But personally I would leave the slot width unchanged.
I am mildly surprised at the chamfering of the sides of the slot, which I don’t think is normal. But I winder whether a previous owner has had problems with the slot gasket being drawn inwards as the board is retracted; this could be an ad hoc solution to that problem. This discussion is very much open to other people to chip in, but in the absence of any advice to the contrary I would suggest cutting the slot with no chamfer, and fit new slot gaskets under tension; cut them longer than the required length, secure one end (which will become the far end from where you will next be working) by means of a screw (driven through that end of the relevant keelband), pull the gasket taut, and while holding that tension drive in a screw at the near end (again through the keelband). Then fit the remaining screws, and finally cut off the surplus gasket.
I suspect that this will be sufficient, and that you will not have a problem of the gasket being trapped inside the slot; but if that does happen then at that point you can consider chamfering the sides of the slot. However I doubt whether you will need to do so; but others may think differently.
Hope this helps,
Oliver
Oliver Shaw
ModeratorAnd if you are going for a new suit of cruising sails, you might like to consider choosing tan, rather than white.
Many reasons, starting with that it is a traditional cruising colour; but in bright sunlight they also produce far less glare, and (perhaps surprisingly) they are sufficiently different to enable your boat to stand out conspicuously from others on the water – which can be a safety feature.
And as an added bonus they look marvellous; see (four) photos of three different boats, each with tan sails.
Oliver
-
This reply was modified 1 year, 5 months ago by
Oliver Shaw.
Attachments:
You must be logged in to view attached files.Oliver Shaw
ModeratorIf you do treat her to a suit of new cruising sails, Edge are the headline make to consider, and you won’t regret it.
A Capella‘s sails, from Edge, are now 17 years old, and despite a great deal of use during my own ownership of the boat they still retain their shape, and they are still good for further service.
Do consider having reefing points fitted, and consider genoa reefing. See my paper on Reefing Systems, in the Members’ Area
Oliver
Oliver Shaw
ModeratorPaul,
Glad you picked the reply, impressively quickly, but you slightly beat me to it, in that I was still editing. Because of an intermittent technical glitch I was initially working blind, in that my typed text was not visible, so I typed with the intention of editing once the reply had appeared! Then a couple of further edits followed.
Do have a look at the final version!
Oliver
Oliver Shaw
ModeratorPaul,
Welcome to the Class, and I am sure you will enjoy the boat. She is (in my opinion, and also that of many others) one of the only two world-class cruiser-racer dinghies; the other boat in that category is the larger (and significantly heavier) Wayfarer.
The arrangement for the Highfield lever is absolutely dependent on the type of mast you have. For the IYE mast shown in your photo, which is one of the two earliest makes of metal mast which was approved for the class, bring the halliard out through the block at the bottom of the mast (ideally the port-hand sheave), then up to the Highfield lever, which should be set so that it pulls upwards. Make an eye in the dyneema, to hook onto the Highfield, and attach a suitable length of line (which may be lighter if you wish) for initially pulling the sail up until the eye will reach the Highfield. Any position convenient for the Highfield around the position shown in your photo is fine.
One word of warning; there is both a safe way and a highly dangerous way to operate a Highfield lever. It is an excellent device if used correctly, but it does have something of a (well-deserved) reputation for serious injury to fingers. Never under any circumstances clasp the fingers fully around the lever when opening it or – still worse – when closing it. Always, always, always close it (i.e. tension the halliard) by pressing it closed with the base (or the “ball” of the hand, keeping the fingers straight, and well clear of the gap between lever and mast! When opening it, to release the halliard, if at all possible use one hand to pull it away from the mast while having the ball of the other hand lightly up against it to check it, in order to prevent it violently flying open; then, once it is “past centre” allow it to open under control.
Hope this helps,
Oliver
-
This reply was modified 1 year, 5 months ago by
Oliver Shaw. Reason: Technical difficulties at time of original posting; working blind because typed text was not visible. Became visible only after posting, so now able to edit and correct as necessary!!!
-
This reply was modified 1 year, 5 months ago by
Oliver Shaw. Reason: Technical difficulties at time of original posting; working blind because typed text was not visible. Became visible only after posting, so now able to edit and correct as necessary!!!
-
This reply was modified 1 year, 5 months ago by
Oliver Shaw.
Oliver Shaw
Moderator> the GP14 class rules expressly forbid single-handed racing (rule 16)
> Entertainingly, the class rules set the maximum luff length and pole length, but don’t require the spinnaker to be symmetrical, or set any restrictions on the pole being configured as a bowsprit, so I might even be class-legal with it!
Both are points that we might usefully address in the next revision of the Class Rules. Purely personally, and not in any way committing the Association, I feel that Rule 16 might usefully be recast in terms of the normal complement being two persons, but with specifically no bar to single-handing; and I think I could make a strong case there. That case would include that (1) the single-hander is normally at a slight disadvantage, except perhaps in ghosting conditions, and (2) the Rules have never (so far as I know) specified upper or lower limits on crew weight. Possibly the youngest (and lightest) ever helmsman in the WLYC 24-hr race, and featured on the front cover photo of Mainsail that year, was George Graham, in 2008, then aged six. He actually had an adult crew, whom I presume was his father; but he could “legally” have had a teenage crew. If a six-year-old plus a teenager are class-legal, which they undoubtedly are, and rightly so, why not an 82 kg single-hander, of much the same weight and perhaps similar overall ability?
On the matter of the spinnaker, and the pole, I am sure that the Rules clearly assume that the sail is symmetric; but I accept that this is not explicitly stated, and perhaps it should be. You are possibly the first person to have raised this issue.
On the matter of the pole, agreed the Rules do not preclude it being rigged as a bowsprit, but the maximum length is probably far too short for it to be effective in that role.
Oliver
Oliver Shaw
Moderator> 1/13-scale replica of Nelson’s HMS Bellerophon based on a GP14 hull:
Found it! And I had misremembered the name; should have been HMS Belleisle, “which as the second ship in Collingwood’s column had acquitted herself famously before being dismasted by the combined fire of three enemy ships. She was built in France as the Formidable, taken, and re-named for the British navy.”
http://www.festinalente.org.uk/belleisle/belleindex.html
Oliver
Oliver Shaw
ModeratorYou are undoubtedly right in saying that this would be outside Class Rules, so that raises the question as to the circumstances in which you might use the rig. For non-racing, I agree that it might be fun to try, although I suspect that it would be not as much fun as a standard symmetrical spinnaker. For class racing it is an absolute no go, but you might perhaps be able to agree local handicap racing at your local club; that would be a matter for negotiation, and ultimately it would be for them to decide. They would then need to allot you a suitable handicap, which might be technically difficult (because of the absence of any hard data on which to base it), but in the first instance you would need to ask them, and they might or might not agree.
There would seem to be some technical issues with mounting the bowsprit in the way you suggest. Attachment to the mast should be reasonably straightforward, except that on many GP14s it would obstruct the spinnaker pole downhaul. Attachment to the stemhead fitting might be more problematic, as you would need a secure and rigid means of attachment while simultaneously spacing the sprit off to one side of the fitting in order to allow adequate clearance for attaching and removing the genoa; and also adequate clearance for genoa furling gear, which I suspect you would regard as highly desirable if using an asymmetric spinnaker. And the combined effect would possibly be to push the end of the bowsprit – which is where it matters – well off the centre line, unless you made an appropriate adjustment specifically to correct that. All these issues are no doubt solvable, but they would require to actually be solved; and the traditional solution to the third one is to offset the heel of the mast to one side, significantly off-centre, so that the end of the sprit ends up on the centre line.
I agree that setting a conventional spinnaker single-handed is a challenge, although in lighter winds it can be an interesting one; I used to do so regularly in light winds until my late seventies, but now that I am into my eighties I wouldn’t still risk it, and I never did it single-handed in stronger winds. A tiller brake helps immensely, so that the tiller can be kept central while you go forward to set (or hand) the spinnaker. In my youth I used a pair of lanyards permanently fixed inside the cockpit, and just quickly tied each of them to the tiller, but over the last 20 years I have instead used a fixed shock cord across the cockpit below the tiller; just lift it and place it on top of the tiller when you want it to hold the tiller in place.
For what it is worth, I have the impression that asymmetric spinnakers are great on a beam reach, but useless on a run; so tacking downwind becomes de rigeur if you are using one. Also it was reported a few years ago that one of the reasons our top youth sailors enjoy racing the GP14 is because it is a very technical boat, and particularly because of the symmetrical spinnaker, which demands far more skill than does an asymmetric, and which then rewards that skill.
Finally, if you are thinking of modifying the rig, two further ideas for you. First, a few years ago a group of Hampshire sailors fitted out a GP14 hull as a 1/13-scale replica of Nelson’s HMS Bellerophon, for a local Regatta; that is worth trying to track down online. It is possible that I may have a record of the URL elsewhere, but it is not to hand at the moment; if I find it I will post an update.
Second, see the attached photo. My own A Capella, sailing in Holy Island Sound in 2010, wearing the rig of a rather nice American 40-ft gaff cutter, courtesy of photo-editing software.
Have fun!
Oliver
Attachments:
You must be logged in to view attached files. -
AuthorPosts



