Model Maker: Volume 3, Issue 34 – September 1953

VOLUME 3 NUMBER 34 SEPTEMBER 1953 iN THIS ISSUE : Swedish 2} c.c. Record Car : ‘“Saida’” New Marblehead Design : “Jo” Hydroplane – for $c.c. engines : Model Boat Propellers : Modernising a Lathe, Pt.1 : “Gerry 0-4-0 0 Gauge Steam Tanker : Working in Plastics : 24mm. Scale Signals : Lineside Industry : Rail Snaps for Interest and Prototypes : ‘Penard V” French |0c.c. Hydroplane : “Model Maker” Yacht Trophy Report : Guiseley Car Meeting : Radio Control at Southend : Rigging and Fittings : Adjustable a Gauge : Superelevated Curves : Jaguar Model : Magnetic Grab for Junior : Test Bench Mu) = ass Se MK IV RADIO CONTROL UNIT TUNED REED—3 CHANNELS The last word for the control of all models which demand progressive, personal and accurate following of multiple orders. In weight and size the complete receiver and battery assembly can be used for model planes of down to 66 inch wing span and boats of 30 inch length. It is also the only type of equipment capable of operating both sails and rudder of model sailing boats. A self-contained transmitter housing all batteries and with 8-foot sectional monopole aerial is supplied with a general purpose hand control box for three channel operation. The receiver uses standard hard valves throughout with an average life of 3,000 hours. Receivers are pre-tuned to the transmitter and once installed, there is no necessity for any further adjustment. The receiver output will operate either escapements or electric motors. Recziver size …… 5 x 3 x 2 ins, Recaiver weight ……… 84 ozs. Receiver battery weight Range exceeds ……… 643 ozs. 1,000 yds, PRICES E.D. Mk.1V, Tuned Reed 3 Channel Unit: Complete… £23.15.0 Separately: — RRGQOOIVOR occ cta trades <3es te £14, Transmitter, and Control Aerial 5.0 Box ............ £9.10.0 All prices include purchase tax ORDER THROUGH YOUR MODEL SHOP “ELECTRONIC DEVELOPMENTS (SURREY) LTD STON-OW THAMES DEVELOPMENT. on S aN SES EORPS 1223 (8, VILLIERS ROAD, KINGSTON -ON-THAMES, SURREY, ENGLAND.: KINDLY MENTION “MODEL MAKER” WHEN REPLYING TO ADVERTISEMENTS F J. HEMSLEY proved a worthy winner of * the Second MopeL MAKER Trophy for 36 in. Restricted Class Yachts held at Barnby Dun, on July 11th and 12th, and organised by the Doncaster M.Y. & P.B.A. It was a triumph too for MoDEL MAKER’s sharpie design Lancet, for the winning boat Lanett was the very first boat ever built to the design, and sailed straight off Tommy Lance’s board ! The winning boat was fitted with a lightweight Vane adapted to 36in. class sailing, and, as the out of water photo shows, had a slightly deepened skeg and cutaway keel to compensate. A sister ship Bowie in the hands of clubmate A. R. Turner unfortunately suffered damage and was withdrawn, or we should have been able to compare conventional Braine with Vane sailing. Second boat home was Hon. Secretary Reeves’ boat Reelew skippered by E. Baker. This is a Duck boat built to the original Donald Duck plans by Adams of Yarmouth and fitted with a half-scale Mullett type Vane, weighing 2% 0z., which has been developed successfully by the Doncaster Club (Arthur Mullett please copy !). Heading: Doncaster Club Commodore and O. C. Thorne Sea Cadets, Lt. Comdr. J. Farrell, takes the salute at the hoisting of the club pennants with full naval ceremonial at Barnby Dun Third was another MopEeL MAKER design Harlequin, again in the hands of Bournville skipper R. Harris. This has had a busy season being close to winning brackets on a number of occasions without quite making them, except for a club event, and will now be retired for the winter to have minor modifications learned in competition incorporated. Left: Second boat, Mr. Reeves’ Renlew which took second place, skippered by E. Baker, in the foreground, while in behind it can be seen The entry was pleasantly widespread, the thirteen boats coming from _ Birkenhead, Brighton, Bournville, Nottingham, Doncaster and Sheffield. One new boat from Nottingham Jack Flash was withdrawn after the first day’s sailing as it was obviously insufficiently tested to compete in an open event, which with the damage to Bowie left eleven active participants. In addition to their variety of club, they also Harlequin, third place boat, with Ron Harris releasing it Left: A group of competitors and supporters on “dry land.”’ Note the shelving sides on water on left Right: the Panther _ fore= groundleads Harlequin. Centre: The Daniels design Blue Belle, which showed such promise in a board with Kreen behind, which came sixth Extreme right: Two vane geared boats, Lamouette(10) and Eagle (5) another Lancer boat which came fourth September 1953 showed a most catholic variety of design and age, varying from 1953 registrations back to a thirty-year-old boat that started life as a Daniels One Metre design and had its stern chopped to make the 36 in. class! This boat, Invader, skippered by R. Beaumont of Sheffield, though narrow in the beam was by no means outclassed and won some good boards. J. E. Tansley’s Heather Glen was another interesting old timer, being a canoe bodied Alexander design in the “two-hundred”’ registration range. We particularly liked Blue Belle, which at one time looked like leading the first day’s ee a sailing. This was a first-ever boat built by its skipper L. Patchett from the Daniels design in his half-guinea book “Build Yourself a a Model Yacht,” and very closely resembles his Midge. It can safely be said that given another season’s experience Blue Belle will win races for its skipper, though Bill Daniels makes no out-and-out racing claims for the design. Another Lancet sharpie that showed promise was in the hands of local clubman J. Schofield, who had a strong juvenile following encouraging his every board! The Barnby Dun water is some 285 yards long and about 40 yards wide, which means that a straight run without retrim is the exception rather than the rule. The absence of local trees or buildings makes it a very true water to sail in, and races were time and again won and lost on skippering rather than boats, so that it was indeed a test of personal sailing skill which to some extent negatived the advantage of the professionally built. boats over home-built craft: though of the first three home, only the winner was amateur made. Heavy rains had somewhat churned the sides of the water, plus an unexpected fall in level, so that handling of yachts was at all times hazardous. Happily no one actually fell in. Winner, F. J. Hemsley, left, wit ( : 3 Lance design Lanett and his mate, A. R. Turner, whose own entry Bowie suffered irreparable damage and was withdrawn. Lanett had a clear lead with 86 points to 67 aan The Doncaster Club who organised the event for Mopet MAKER made a magnificent effort with printed souvenir programmes, a large marquee for refreshments and shower shelter, invited Mark Fairbrother to act as O.O.D., and through the good offices of their Commodore had the Sea Cadets in camp on the site to provide full Naval Ceremonial of the hoisting of the clubs’ pennants, and act as runners, scorers and officials throughout the meeting. In addition to the Trophy, the winner received a bottle of Drambuie, most distant entrant’s prize, and Five Guinea voucher for winning with a MopeLt MAKER design. Other prizes included a Record metal plane, oyster butter dish, Biro pens, chocolates, and a special presentation to O.O.D. Mark Fairbrother. Oxide A FIRST-CLASS MARBLEHEAD DESIGN FOR BEGINNER OR EXPERT ee BY D. A. MACDONALD ‘Le design of Saida was begun about two While D. A. MacDonald may be best known to model yachting enthusiasts as the very successful owner-skipper of many of H. B. Tucker's more years ago, with the intention of producing a carefully balanced M-class of conventional design to be built as a “trial horse” for Mr. H. B. Tucker’s design Jemima Duck, which was then being worked out in the light of experience gained with its predecessors. The design requirements for the “trial horse” called for a boat of about or slightly above the average displacement of successful craft at that time, and capable of a high standard of performance under both heavy weather and very light weather conditions. The design must also avoid any untried or unconventional features, and must achieve a very good hull balance to ensure reliable performance under all conditions of sailing, with a minimum of “tuning- revolutionary designs, “Donald,” “‘Quackie’ including the Duck family and heir \big sister in the Marbleheads “Jemima,” as well as such A Class boats as “Lynx”, he is also a designer of considerable merit in his own right—a state of affairs certainly to be expected from so long an association with the master. We hope readers will find “Saida’, which participated in the 1953 Nationals under the name of “Eada” skippered by Barry Barnes, as satisfactory a craft as it has proved to the designer. baad up.” However, when the design of Saida was nearly complete, developments in the design of Jemima Duck indicated that a more suitable trial horse would be a boat of over 22]b. displacement. An enlargement of “Saida” did not appear to be a satisfactory solution, and work on this design was suspended. It was not resumed until early in 1952, when an interval in other activities allowed me time for some work on the drawing board. The design seemed to be well worthy of completion, since the requirements laid down for its primary purpose were just those which the majority of model yachtsmen would stipulate for a boat for consistent racing. I had also been urged to complete the design by several members of local clubs, who had seen the design in its early The “text-book” wave formation seen in the heading picture right, is Eada indicative the first of the efficiency of Saida. On boat built to this design, placed sixth out of twenty entries in the Marblehead Nationals at Hove, in the hands of her young skipper, B. Barnes 509 oT MODEL MAKER stages and were attracted by it. Incompleting the design, therefore, I have worked carefully to the original specification; no design “tricks” have been employed, and no attempt made to achieve an exceptional performance in any one set of conditions at the expense of all-round efficiency. Great care has been taken with the volumetric balance, with the result that there is no measurable change in the position of C.B. up to heeled angles of 25°. The curves of areas shown, which are for 20° heel, will confirm this. The excess of heeled over upright displacement is rather less than in many designs: this ensures that, when heeled, the boat will “sit down” and use her overhangs to fullest effect. The extra stability. 1s a The ratio of 34:1 chosen for Saida compromise based on experience and suited to the form of the hull. The proportion of jib to mainsail is based on the contention that both sails should have approximately the same aspect ratio, an arrangement known to work out well in practice. The small suits have been designed so that the lead of C.E. over C.L.R. progressively increases as sail area is reduced. The change is quite small, but makes for better all-round sailing under heavy weather conditions. The table of weights has been drawn up on a realistic basis, with an eye to the amateur builder who may not wish to attempt an ultralight hull, at the expense of strength and the risk of subsequent distortion. The lead as drawn will cast at about 151b. This will allow buoyancy is also distributed in favour of the ends of the boat, and the result in practice is a very nice heeling action, free from the jerkiness associated with high inherent stability. a good margin for cleaning up a casting if rough, and will also allow the builder of a light hull to retain his saved weight as extra ballast. In the design of the lead keel, allowance has The fin and skeg have been designed and positioned to ensure a good dynamic balance together with a low C.G. Dynamic balance considerations unfortunately present an elusive and incalculable problem to the designer, and experience is still the only sure guide. In this design all influences known to be harmful have been avoided or minimised and the practical results indicate that the care taken in this respect has been worth while. By continuing the raking FULL-SIZE COPIES OF THIS ONE-SIXTH REPRODUCTIONJF ARE} SOOO MARBLEHEAD ‘saioa |] [| TM) D hea design mid-section through the garboards down to the base of the fin, the latter has been made to grow naturally out of the canoe body, and good streamlining in the garboards has been achieved. Also, in designing the fin and garboards, sections were taken out at | in. intervals and additional waterlines at 4 in. spacing in the region of the garboards. - yee (He & Su Sa SO me eal re TT “) ia aie aK