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Oliver Shaw
ModeratorAnd to add to Windy’s query about Series 1 as against Series 2, dare I suggest that the choice is not entirely one-sided, and particularly so for cruising.
Both are great boats, of course; that almost goes without saying, and especially on this forum!
One of the design intentions of the Series 2 was that it should be quicker and easier and cheaper to build than the Series 1; having never built either of them I cannot make that comparison from first-hand experience, but my understanding is that this is indeed the case.
In terms of the finished boats, the Series 2 has a number of benefits, particularly for cruising. It has massive buoyancy, and in the unfortunate event of a capsize it is remarkable how rapidly it will then clear the hull of water once you right the boat and get her sailing; if there is enough wind to have capsized you in the first place then you can expect to be able to sail her dry within about two minutes (and possibly less) of getting her righted again. By contrast, if you capsize a Series 1 boat you may well need to resort to a bucket to bring the water level down to a point where you can start to sail her dry; my own experience of deliberately flooding a Series 1 with newly installed transom scuppers (in order to try them out) was fairly disastrous, and my very rare subsequent capsizes were not much better; and I have heard mixed view from others as to whether the transom scuppers actually work on a Series 1 boat.
An unrelated added bonus for cruising is the commodious storage pockets along the sides of the boat.
All that sounds a very strong hand in favour of the Series 2. But … …
First, in the event of a capsize the Series 2 is very prone to inversion, precisely because of the underfloor buoyancy. Various developments have attempted to address this problem, but whatever version is sailed I would strongly recommend carrying masthead buoyancy as standard; the popular 9-litre masthead float will not provide enough buoyancy to prevent inversion – indeed it is not designed to do so – but it will buy time during which the competent skipper/helmsman can take the necessary steps to right the boat. Inexperienced skippers may wish to opt for the 40-litre masthead float intended for training establishments.
Second, the underfloor buoyancy reduces the space between the thwart and the cockpit sole. Personally I never found that a problem except for one situation; if you wish to camp aboard – which I appreciate is firmly a minority situation – that reduced space makes it impossible to sleep aboard the boat underneath the thwart, and it is necessary to rig some sort of sleeping platform above the seating instead. By the same token, in a Series 1 boat, any small amount of water that comes in overnight, via the transom flaps or otherwise, remains below the floorboards, so you can keep your kit dry; in a Series 2 any such water flows along the cockpit sole to the self-bailer pockets, and once those are filled any further ingress of water produces a wet floor, so it can become more difficult to keep your kit dry.
The above may possibly influence your decision whether to build Series 1 or Series 2.
Finally, a correction to the terminology; the terms Mk1, Mk2, etc (up to Mk IVa) all refer to fibreglass boats; the terminology for the different types of wooden boats is Series 1, Series 2 (and, I think unoficially, Series 2a).
Oliver
Oliver Shaw
ModeratorThere is a very long history of successful boat building (including yacht building) making the best use of whatever timbers are available locally; and it is entirely reasonable to try to identify which of the timbers available local to yourself are most suitable for the job, irrespective of what the plans say.
Although I would not normally recommend sending retail quantities of timber half way across the world, it might be worth your while to have a look at the Robbins Timber website, if only for an analysis of the characteristics of a wide range of different timbers; Robbins Timber https://www.robbins.co.uk/products-prices/marine/
Another useful website if you are considering Douglas Fir might be Collars, again for information on the characteristics of the timber, rather than expecting to buy from them at that geographical distance. They are leading mast and oar manufacturers, and they use either Douglas Fir or Sitka Spruce, the choice depending on the particular type of mast, because the two woods have different characteristics; http://www.collars.co.uk/uk_galaxy/info/1/masts/15/timber
Also some information here on obeche; https://www.woodshopdirect.co.uk/planed-all-round/obeche-timber/ .
Also worth having a look at The Wood Database; https://www.wood-database.com/wood-filter/.
In regard to rot resistance – always obviously relevant for boat building – I note from the last of these that Douglas fir is rated as moderately durable, whereas obeche is rated as poor; so it is a little surprising that the plans specify obeche!
My recollection of the early GP14s which I have owned in the past is that longitudinal framing (stringers, chine pieces, carlins, etc., were all in a light-coloured wood which I tacitly assumed to be pine. I cannot be sure about the kingplank and the carlins. However I am absolutely sure that the knees were mahogany.
Hope this is of some help,
Oliver
Oliver Shaw
ModeratorWelcome back!
Sorry to hear about your parents’ medical issues.
I don’t actually have any tent plans as such, but on A Capella I have occasionally used a boom tent made by the previous owner of a Series 1 boat which I bought in 2004. It is basically a simple A-shape, with a modest extension forward of the mast, and access/egress at the stern; see the photos.
Securing the bottom of the tent is a compromise, because I used it only occasionally, and I did not want to deface my then brand new boat by fitting lacing hooks or other clips around the hull. So instead of using lacing hooks or other fittings I used to rig a 6 mm rope around the hull immediately below the gunwales, tensioned with shockcord, and tie the bottom of the tent on to that, doing the job that with a land-based tent would be done by guy ropes and pegs. That works tolerably in light winds, but typically some part of the bottom pulls away and lifts the girdle rope above the gunwale at some point during the night; but in light winds that is tolerable. I have never put it to the test in strong winds.
Condensation is an issue, and I think at least one pair of proper tent ventilators are essential; this tent doesn’t have any.
Headroom is very limited. If I were still into camping aboard, and were thinking in terms of a new tent, I would be strongly inclined to go for a design which gave adequate sitting headroom across the boat. That could be achieved by the use of athwartship hoops made from light fibreglass rods, perhaps adapted from a commercial tent using that system. I have also occasionally seen Wayfarers using tents supported by a pair of longitudinal ridge poles, one either side of the boat, mounted to the shrouds forward, and on an athwartships bracket secured to the boom at the after end. One obvious issue for either design is where and how to store the tent frame while sailing, but other dinghy cruising sailors do manage that.
It might be worth an enquiry to the Wayfarer Association, and/or to the Dinghy Cruising Association.
Hope this is of some help.
Oliver
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ModeratorPaul,
Not to worry about the delay; explanation accepted, and I was perhaps a tad hasty. But perhaps you can understand where I was coming from!
Regards,
Oliver
Oliver Shaw
ModeratorPaul,
Was my prompt (and researched) answer to your apparently urgent enquiry of any help to you?
By now, my links to masts advertised second-hand must be considered out of date … …
Oliver
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This reply was modified 3 years, 10 months ago by
Oliver Shaw. Reason: Update
Oliver Shaw
ModeratorPaul,
Unfortunately your photos have not uploaded; you need to reduce the file size and try again.
However some general principles may be helpful:
First, contact your insurer; without the photos I know nothing about what the damage is, or the circumstances, and likewise I do not know what valuation you have insured for, but it is worth checking whether you have a valid claim. If it is accidental damage, and the replacement cost is within your insured limit, you probably have.
Second, any major dinghy chandler should be able to source a replacement mast for you.
- Sailboats.co.uk appear to have taken over from the now defunct Speed Sails – they describe themselves as a main dealer for Speed Sails, and a page on National Historic Ships gives an address for Speed Sails which is the same as the address Sailboats.co.uk quote on their website, although it is not even the same town as the address which they had in their heyday. They list a number of Selden accessories for the GP14 but not the mast itself; however don’t assume that the absence of something on their website implies that they cannot source it for you, and since they are listed on the Selden “find a dealer” map I would expect that they probably can. It is at least worth asking them..
Third, the Selden website has a “find a dealer” service here.
Fourth, if for whatever reason a brand new mast is not an option, have a look at the Classifieds on this site. At the time of writing there is currently one listed. Remember that a series 1 mast can be converted to series 2 if necessary (but not the other way round, although for a boat as young as yours the latter will not be an issue); the series 2 mast is 12 cm shorter, because of the higher location of the mast step.
Fifth, it is worth doing a search on eBay. There are 6 masts plus a complete boat currently listed here, although I have not checked any of them out; some may be a lot older than your mast, and perhaps less suited to a modern race-spec rig.
Sixth, depending on what the damage is, a repair might perhaps be possible.
Hope this helps,
Oliver
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This reply was modified 3 years, 11 months ago by
Oliver Shaw.
Oliver Shaw
ModeratorI do wonder whether on your older boat, with that much rig tension, and no mast steep conversion, you are straining the hull by unduly depressing the mast step. If so, you could be heading for structural problems; metaphorically pushing the mast out through the bottom of the boat.
That much rig tension – on its own – will be generating somewhere around half a ton force downwards on the mast step, before the wind loading even starts! The boat was designed in 1949, long before such high rig tensions became usual, so it was never designed for these loads.
It might be wise to settle for slightly less rig tension!
As for liking your older boat; if she is a bit special for you, and especially if she is a wooden one, go for it!
Oliver
Oliver Shaw
ModeratorThinking about this from a physicist’s perspective, is the front face of the mast still in free air in the slot, and thus free to move further forward, or is it butting up against either the front of the slot or a chock?
If the front face is still free to move forward then the kicker should have no effect on rig tension; the forces are all internal to the mast/boom/sail/kicker system, and the position of the hounds does not alter, and so the tension on the shrouds should not alter.
However it the front of the mast is prevented from moving any further forward the effect of high kicker loads must be to pull the hounds aft; which will increase the tension in the genoa luff and reduce the tension in the shrouds.
But I concur that if your shrouds are visibly loose, other than the leeward one being a little slack when driving hard to windward, then either there is something very odd going on or you are perhaps using excessive kicker.
Oliver
Oliver Shaw
ModeratorThanks, Steve; and I absolutely see where you are coming from, but for other reasons I nonetheless beg to disagree.
A muscle box is potentially much too powerful for the strength of the early hulls, which were never designed to cope with the tension which a muscle box can provide. Remember that the design dates from 1949, when tension was normally applied by little more than sweating up on a horn cleat, perhaps aided by the crew pulling the middle of the forestay forward. Come to that, the hulls weren’t designed for the loads generated by Highfield levers either, but that is less extreme, and long experience (not mine, but that of the Class as a whole) has demonstrated that the hull can safely handle that; there is enough safety margin in the design.
But long experience (again by the many members of the class) has also demonstrated that using a muscle box, or a powerful cascade tackle, can cause serious damage to the early hulls. That, indeed, is why the official mast step conversion was developed; to adequately strengthen early hulls, by spreading the load, in order to enable modern rig tensions to be used. There is no official equivalent for the early GRP boats, but they are certainly not immune from the problem, and I have just once seen a well-engineered DIY mast step conversion on such a boat (at Neyland YC, in (I think) 2007, when we were there for the UK National Cruising Week).
Of course, if one installs a muscle box there is no need to tension it to its maximum potential; but even if you fit a marker it is still fatally easy to do it inadvertently.
Yes, one can cleat off a muscle box on the mast, and not use a 2:1 inside the boat, which is exactly the arrangement I had in A Capella, but that still gives a mechanical advantage of 8:1, which is rather a lot for the early boats. Working out the M.A. of a Highfield is more complex, but the headline ratio is that which applies when the lever is perpendicular to the mast; I happen to have a dinghy Highfield on my desk as I write, and the crucial measurements there are 35 mm operating radius for the point where the load is taken, and 100 mm for the centre of the pad for the operating hand. That gives a mechanical advantage of just under 3. Alright, the ratio increases as the lever is closed, because the operating radius for the load decreases but that for the hand at the end of the lever does not, which is what makes it complex to calculate, but it is also the case that very little additional movement of the halliard takes place during that phase; it cannot possibly be more than the 35 mm operating radius of the load attachment point, so the tension will increase by only a modest amount in the final quadrant of closing the lever – although it is complex to calculate how much, and one would need details of the halliard length and elastic modulus to calculate it. Overall I feel that a little over 3:1, perhaps 4:1 is fair for a Highfield, which is about half what a muscle box will give even if you do not further boost the latter by a 2:1 inside the boat.
There is however a safe way to use Highfield levers. When loading up the system – i.e. applying the tension – you should use the ball of the hand to close the lever, keeping fingers well out of the way. When unloading – i.e. opening it – use one hand to initially pull it open, with the ball of the other hand (and, again, fingers well out of the way) to act as a backstop to prevent it taking charge and opening with a slam; once it is about half-way or perhaps two-thirds open there will be little load on it, and the danger is past. Simon will (I hope) remember me demonstrating this during the cruiser training course.
Like a lot of tools and fittings which can potentially cause injury, it is important to develop safe techniques for using them.
Oliver
Oliver Shaw
ModeratorOne correction to my earlier post: I wondered just now whether I had been mistaken, so have looked up a photo taken in 2005, from which I see clearly that the genoa halliard on Strait Laced was wire; it was the main halliard that was pre-stretched polyester, of (I think) 5 mm diameter. Apologies for the confusion, but blame failing memory; I sold that boat around 13 years ago.
However that does not invalidate the rest of the advice, nor that of Arthur or Warsashod; there is a lot to be said for going for dyneema. You would probably get away with pre-stretched polyester, with a Highfield lever, as I did in the seventies with my earlier GP14, Tantrum, (although that was without reefing equipment), but dyneema will have even less stretch.
One important detail is to terminate the ends in splices, not knots; dyneema (and other HMPE ropes) will not tolerate the tight turns involved in knots, which weaken the rope very considerably. RYA did a report on that a few years ago; Link here.
Oliver
Oliver Shaw
ModeratorSimon,
(For others reading this correspondence, I should mention that I have met Simon and I know his boat, after a fashion, and know that it is one of the early GRP boats; Mk 2 I think, from memory.)
On your boat, provided she is in sound condition (as indeed I believe she is) you should be able to safely install a Highfield lever.
One word of caution; it is highly likely that the lengths of your halliards will be different from the modern standard lengths, which are designed around a different mast and a different rigging system. So a ready-made wire halliard is very likely not to fit, and in all probability you would need to get one made to fit your boat.
I would expect that you could also use 6mm polyester, either three-strand or braided, provided it is the pre-stretched type; and on Strait Laced I am fairly sure that I successfully used 5mm, with my reefing gear. Certainly that was fairly standard when the boat was new (then of course as 3/4-inch pre-stretched terylene), although that was not in the context of reefing equipment.
(The old standard was to size ropes by circumference, whereas the modern standard is to do it by diameter; conversion factor is p, which is slightly more than 3. 3/4 inch circumference on the old system therefore corresponds to 6.1 mm diameter on the new system, so the corresponding standard size is 6 mm; but modern sheaves designed for either wire or dyneema halliards tend to be narrower, so on a modern boat 6 mm may be too fat for the sheaves; I found that problem on A Capella, although it was borderline and I managed to live with it.)
However modern high modulus polyethelene ropes (e.g. dynema or spectra) would be even better that pre-stretched polyester, and the stretch of those is very similar to that of wire, i.e. minimal Using rope rather than wire does have some advantages for the average layman owner/skipper, in that you can tailor the length to your own boat, and can then make the splices yourself in the right places.
Most owners, if using wire, need to get it professionally spliced – although I do know one “lay” owner who has his own Talurit press, and who did the wire splicing for me on my vintage boat.
Hope this helps,
Oliver
Oliver Shaw
ModeratorThank you again; several good suggestions coming in.
Oliver
Oliver Shaw
ModeratorMany thanks for that.
Oliver
Oliver Shaw
Moderator> The rest looks really good!
I agree; some very nice-looking work there. Well done!
Oliver
Oliver Shaw
Moderator> but it will always be slightly compromised whatever you do. Whether this matters depends upon your aspirations.
That is very interesting.
When I had A Capella built she was my first boat with through-deck sheeting, but she was also specifically intended from outset as a cruising boat, so I had a full reefing facility, including roller reefing for the genoa. For her first season I temporarily compromised by “borrowing” the best sails (which were excellent) from my other boat, Strait Laced, but I did find that I had a problem of sheeting angle when the genoa was reefed, although no such problem arose with the same sail on Strait Laced (which had on-deck sheeting). I solved that on A Capella by the use of an additional free-running control line, rather like a barber-hauler but in reverse.
For her second season I had a new suit of cruising sails built by Edge Sails, and in the light of my experiences with sheeting angle I asked for the genoa clew to be cut just a little higher than standard. This worked well, and although it was still a compromise it was a good one; the sheeting angle still changed between reefed and full, but at all stages it was acceptable.
But it is interesting to learn that in the non-cruising fleet genoas intended for through-deck sheeting are also cut differently.
Oliver
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This reply was modified 3 years, 10 months ago by
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