UK-Cherub Class

Get Your Heart Racing

How it all began

Cherub - A Fast Easily Built 12ft dinghy

(Sea Spray Magazine June 1952)

During the early part of 1951 I designed for myself a twelve-foot hard chine boat of similar type to the English National fourteen foot Merlin Rocket class, but with a less extreme sail plan, I wanted to compete in the pennant class. The restrictions of the Pennant class consist of maximums on length and sail area, the former being 12 feet, the latter 100 square feet for working sails and 90 for the spinnaker.


It did not seem necessary to use the full sail area and it was finally decided to use 93.5 square feet, although on a tall mast, which would provide a more efficient rig. The main reason for deciding on a square bilge design was that it allowed the use of 3/16 inch resin bonded plywood (obtainable in 7ft x 3ft sheets), which is lighter and easier to use, as well as to obtain than planking. This turned out, to my considerable surprise to be cheaper than the latter.

With the English racing-dinghy type of lines (deep-chested planing hull) in square bilge the boat should be stiffer in a breeze, perform as well on the wind and perhaps better off the wind than a similar round bilge boat, except in very light weather. With the extra buoyancy obtainable in square sections and the same amount of rise of floor of the keel, it was possible to flatten out the run aft more than would be wise in a similar round bilge design.

I had planned to start building as soon as Examinations were done, which meant early in December, but during the early stages of developing the design, Ray Early, who had Mischief in the Pennant Class, decided to build from my plan .As he was ready before I was, we began his boat, to be named Cherub, and my own was eventually put aside indefinitely

Cherub proved exceptionally easy to build; keel chines, etc almost falling into position around the long, easy curves. In eight weeks of spare time work, aided for only half of this time on Saturdays and a couple of nights during the week by myself, Ray finished the job. When she was rigged up on the lawn for the first time he felt, I think, not a little proud. So did I Cherub was the first full-size boat from my designs for anyone other than myself.

Our pride proved justifiable, however. Cherub on her debut “ got up ” and planned whenever the sheets were eased a few inches, and has since sailed off scratch in the Pennant class until she has now a fairly comfortable lead on points (She won the point shield and The Auckland Dinghy Association Championship)

At first she seemed extremely tender, and just before the start of her first race she capsized to windward spectacularly. With a little time to become accustomed to her, however, she has proved easy to keep steady. Right from the start she has been easily held down and would, in fact, hold all the sail area allowed in the class. This is not really surprising however, for she is quite a roomy 12 footer, In spite of more than the usual amount of decking both fore and aft.

Costs proved considerably better than predicted, for the original estimate of forty pounds including sails but exclusive of labour, was reduced to thirty-two pounds. Fittings were all made from odd scraps of stainless steel and have proved extremely successful in spite of their lightness

The hull construction is very light by New Zealand standards, but used in conjunction with the plywood, has proved more than sufficient, showing not the slightest sign of working. For the plywood, unlike conventional planking, braces the whole form and seems 100% resistant to the effects of damp and heat. It is also simple to repair: a sharp object will make only a small, clean hole which is easily repaired in a short time as we found after encountering a Wanganui's bowsprit, while any large object would require a great deal of force to render any damage.

John Spencer

(This article was reproduced in Sea Spray in March 2000. Many thanks to the publishers for permission to reproduce it.) The photo was supplied by Peter Tait of Firebug HQ. The photo owner knew Spencer and/or the builder at the time and related the story of how the Cherub got its name. John didn't own the boat, he was a broke architectural student, but helped the owner build it. Apparently the owner had a small and sweet daughter who was constantly refered to as cherub. It was 'cherub this' and 'cherub that' all the time. So much so that the new boat became Cherub too! The photo was taken on launching day in Auckland New Zealand. The twelve footers in those days were known as the Penant class, hence the sail insignia and were a mixture of all sorts. Cherub sailed circles around them from day one much to the delight of the young designer!

Editorial Comment…

Fifty years on its interesting to look at this article with hindsight. I hope it won't be regarded as unfair to say that in 1951 New Zealand was not reckoned amongst the leading Yachting nations of the World. They had been sailing International 14 footers for two or three years, and were obviously very much aware of what Uffa Fox and a then young Jack Holt were up to.

Anyway, when this young Kiwi architecture student (well expatriate Australian really, but John Spencer was always a New Zealander in everything but birth certificate) sat down to design himself another boat no-one could have expected anything world shaking. But let's examine what happened. He starts with a Merlin Rocket (U.K. Clinker built restricted development class, round bilge), and decides to build it hard chine in plywood so the boat is lighter.

  • Key Point No 1 - Make the boat light!

The characteristics of the hard chine shape (and possibly the lower weight enables

  • Key Point No 2 - Lower the Rocker

He also anticipates off wind performance gains from the hard chine shape. The boat also turns out to be much easier to build and cheaper.

  • Key Point No 3 - Make racing boats accessible to many more people

And finally

  • Key Point No 4 - It Wins!

I'm not going to claim that all these key points weren't spotted elsewhere - especially number 3 - but I will claim that no-one put it all together as early and as thoroughly as John did. I'll also claim that John was a direct and irreplaceable influence that made the Kiwi sailing scene so exciting and vibrant in the 60s and 70s. Finally surely no-one will disagree that the result of that exciting sailing scene is the America's Cup, and the fact that New Zealand is now one of (if not the) the leading Sailing Nations in the world.

Jim Champ April 2000

history/how_it_all_began.txt · Last modified: 2013/06/25 15:55 (external edit)