Merlin Rockets by Keith Callaghan
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The Move to Liberalise the Construction Rules - The 4 Plank Merlin (1972-73)

I was recently (July 2003) re-reading the "Merlin Rocket Book" (by Jim Park & Ian Holt, published in 1986 to mark the 40th anniversary of the Class), and was intrigued to see that the MROA Committee's proposal in 1972 to liberalise the construction rules were given barely a mention. As it was almost 30 years to the day that the members at the 1973 AGM in Poole voted to reject the proposals, I thought it might be an appropriate occasion to recount my personal memories of this crucial event in the evolution of the Class.

At that time I was a member of the MROA Committee, and actively involved in the design and development of the Class, as well as the racing. From my present perspective, it was the time of the Merlin Rocket's greatest popularity, as objective statistics like numbers of new boats registered and numbers of boats at the Nationals can demonstrate. There were more designers and builders than at any other time in the Class's long history. Yet the Committee was looking to the future, as a development class should not rest on its laurels. Some of us were aware of the rejuvenation of the National 12s that had taken place since some quite radical changes to the construction rules had been boldly implemented. We were determined that the Merlin Rocket should stay at the forefront of dinghy development in the UK, and we discussed ways how our boats could appeal to a wider range of people. Costs were starting to rise (a period of high inflation was about to start), and our cherished imposition of a price limit on boats and sails was becoming a joke - we were too often having to go to the RYA to get the limits raised. Some said that the £1000 Merlin was not far off! So the logical conclusion that we came to was that a simplification of the construction rules would, among other things, allow alternative and cheaper methods of construction, simplify building by amateurs, and facilitate the production of a viable GRP Merlin.

What follows is based on my contemporaneous written record and press comment, and my memory (not perfect after 30 years!). I welcome comments from any reader of this page, especially if you can correct me about matters of fact, or add another perspective to the narrative. I would also like to hear from anyone who has minutes of the relevant MROA Committee meetings, and also the 1973 AGM - regrettably my generally comprehensive archives do not contain this material.

3 March 1972
The MROA Committee decides to commission the building of two experimental prototypes using new construction methods.

4-5 March 1972: Hamble Warming Pan .
I spoke to Spud Rowsell and others after the sailing: the Committee had taken the decision to ask the RYA for permission to build two prototypes - a smooth skin boat and a 4-plank clinker boat. Spud couldn't see why the Class needed new construction methods at a time when it was growing faster than ever before. I explained that the Committee thought that there should be some way of

  1. Having more builders in the Class (especially in GRP), and thus increasing the number of boats built.
  2. Allowing easier GRP construction.
  3. Reducing the price of boats.
  4. Facilitating production of kits for home builders.
  5. Making amateur construction easier (and thus encouraging amateur designers).

Spud seemed to agree in principle to these points, and expressed a willingness to build a 4-plank boat, but he thought that the smooth skin option would be very expensive to produce. This also seemed to be the opinion of others that I spoke to.


Two experimental Merlins, one entirely smooth skinned, the other a 4-plank design, are to be built within the next few months. The Class Association Committee gave the go-ahead to the idea at its meeting last Friday (3 March) and Keith Callaghan is working on the design.
All that is needed now is the approval of the RYA to allow the boats to race on equal terms with existing Merlins.
The idea behind experimenting with new building techniques is to cut costs - the stitched hull is likely to be around £100 cheaper than a conventional hull - and to encourage home builders.
Also, with an eye on the future, the Class Association committee believes that developments such as these could help to ensure that the class continues its present healthy growth rate - 200 new boats are being built this year, the biggest increase by any national class.

6 March 1972
I phoned Ken Ellis (MROA Chairman) and told him of the opposition to a smooth skin hull form. He suggested we might try a hard chine type like the MANTA International 14. He suggested I talk to Tom Vaughan on the International 14 stand at the forthcoming Crystal Palace Dinghy Exhibition.

11 March 1972
At the CPDE I spent a lot of time talking to Don Woof (National 12s) and Tom Vaughan and Owen Cracknell (Int 14s). Don Woof suggested merely doing away with the maximum plank width rule, and stating that GRP boats must be produced from a plywood plug (ie GRP boats must be capable of being produced in plywood). The Cracknell MkVI International 14 was on display - a 'developed ply' hull made from 5mm ply.

13 March 1972
I phoned Spud to discuss the 4-plank boat. He agreed that we should retain the clinker look, ie just do away with the maximum plank width rule. He wanted to build the boat, and we agreed it should be ready for the Nationals, so a large number of members could have a look at it. This implied that the boat would have to be bought by someone already in Spud's customer 'queue', and Richard Davis's name immediately sprang to mind. His boat was due for completion before the end of May, and Spud therefore would want the plans by Easter. I offered to make the frames and bring them down at Easter. Then I phoned Ken Ellis, who agreed to approach Richard Davis.

14 March 1972
Richard Davis phoned me. He had not yet heard from Ken Ellis, so I told him of our proposal. He said he was against 4-plank boats in principle, but would be prepared to try one out - provided the Association covered the cost of the hull, and that he could get another boat from Spud in 1973.

15 March 1972
Ken had phoned Richard and obtained his consent. It only remained to sort out the detail - funding, certificate, etc. I then phoned Spud, who said his building jig would be vacant over Easter, so we could erect the frames and check them out. He said he had 35 boats on order (ie up to July 1974), so it would be difficult to fit Richard in again, but he hoped to employ an additional skilled boatbuilder, so his delivery time would come down.
Later Ken told me that there had been a RYA Centreboard Committe meeting, and that temporary racing certificates had been granted for two boats.

I went to the Ranalagh Trophy Open Meeting on 16 March, and after the racing discussed the new proposals with Ken Ellis, Richard Davis, and others. There was a rumour going round that many of the northern MR sailers were opposed to the changes, so later that week I wrote to Neil Henderson of Leigh S.C., in an attempt to promote our case.

Yachting and Boating Article, 16 March 1972

31st March 1972
I drove to Exmouth for the Exe Easter Meeting, with the four-planker's building frames on my roofrack for Spud Rowsell. Assuming that everything was now cut and dried, I talked to Richard Davis the following morning, but he said he was still unsure about committing himself to having the boat built, especially as Ken Ellis had not yet written to him to say that the MROA would underwrite the hull.
That evening I discussed the matter further with Richard, but he had decided not to have the 4-plank boat - no-one he had talked to that day had said it was a good idea.
On Monday evening I put the frames back on the roof rack, and drove home.

April-May 1972
I had to report to the MROA Committee that we had been unable to get a 4-plank boat commissioned. My friend Bernard Wormald, who had built the first 'Hotspur', and was now secretary of the Association, gallantly stepped in and volunteered to build a four-planker. He called the boat Fourunner [sic] (MR2658), and he took the hull to the Falmouth Nationals, though it was not fitted out and ready to sail. But Bernard's home-made effort did not impress the members as a Rowsell Boat might have done, and it was clear that the proposals were in trouble.

Yachting and Boating Article on Four Runner, 25 May 1972"

Yachting and Boating Article, June 1st 1972

'Fourunner' sailed in various open meetings and events over the following months, but at the MROA AGM at Poole in 1973, members rejected the rule change proposals put forward by the Committee. The most upsetting aspect for me, however, was the personal attack on myself and Ken Ellis by the 1972 National Champion David Speirs at the AGM. Speirs later apologised to me, but the damage was done. I wondered why I was spending so much time on the matter, and I assumed a lower profile in MROA affairs after that. Speirs, incidentally, had already emigrated to Canada (he was back on a flying visit to compete at the Championships), so took no further part in Merlin Rocketry.

In the "Merlin Rocket Book" (p73) Jim Park surmises that I was so disillusioned by the 4-plank episode that I left the Merlin Class. This is totally untrue. I continued to sail in Merlins with Patrick Blake and then Colin Humphrey until 1978, when Colin left to work abroad and family commitments took over.


Past and current members of the MROA will no doubt draw their own conclusions about the significance of the 'Four Plank Episode'. It has virtually disappeared from the official annals of the Class, but my own view is that the 1973 decision marked a watershed, after which the Merlin Rocket, as a development class, went into decline. From the late 70s, new boat numbers declined significantly: more boats were built in the heyday period 1970 to 1975 than have been built in the 30 years since. Now the Class is FRP and virtually one-design, as the construction costs and techniques required to tool up and produce a new design which might compete with the high tech FRP Winder-Wonder make it almost out of the question to innovate. What an anachronism - to have a 'clinker' hull form made out of modern materials.
I designed and built my first Merlin when I was 18, as I could not afford a 'Professional' boat, and fancied trying my hand at dinghy design. Phil Morrison designed and built his first Merlin in similar circumstances. My Merlin cost me about £150 to make (1966 prices), and it was competitive. That could not happen now. But International 14s, National 12s, Cherubs and the other development classes have constantly evolved their construction rules. Unlike the Merlin Rocket, innovation is still their stock in trade. Yet time moves on and things move full circle. A class which maybe 20 years ago was starting to look dated has now taken on a 'classic' image which is increasingly attractive to top class sailors and indeed anyone with the requisite skill and the cash to acquire a modern Merlin Rocket.

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Last updated 8 December 2012