Model Maker: Volume 4, Issue 44 – July 1954

VOLUME 4 NUMBER JULY 1954 Model Maker Yacht Trophy : Record Cars Described : Two New Beal on TT Railroading : ‘‘“Windsong” Marblehead : Radio Control Test Equip- ment : “Sirius Star” : New Tucker Marine Steam Unit : Racing Tips for Model Car Novices : “Crested Steam Goods” Loco : 0 Gauge “Ella” The Learner’s Passenger-Hauler : Trade Reviews : Letters MODEL MAKE REPORTED BY HE only unco-operative gentleman in the 1954 M.M. Trophy was the Clerk of the Weather, although he at least gave everyone a chance of having what he liked by laying on everything from flat calm to a snorting noseender. Everyone could have done without the cloud and the sometimes really heavy . showers, though, especially the camera-wielding fraternity which, of course, included us. The meeting went off with that deceptive smoothness which bespeaks first-class organisation; for this our thanks are due to Mr. J. A. Bruce and other members of the Birkenhead M.Y. P.B.C. A splendid entry of 20 Marbleheads necessitated sailing in two fleets, and after a brief address by the O.0.D., Mr. B. H. Priest, the crews lost no time in getting their craft afloat. Early heats were confusing, since the very light breeze flirted all round the lake and, indeed, at times disappeared. Some skippers used spinnakers in one or other direction, some used them in both, and some didn’t use them at all! Towards lunch-time, however, the breeze stiffened a little and set in its prevailing direction, along a diagonal across the water. Unfortunately the fresher breeze brought the first spots of rain, but at least competitors knew what to trim for. By the time the lunch-break came Wolverine and Black Hawk had crept into the lead of their respective fleets, a possible reflection of the experience of their skippers. In a still fresher breeze and more frequent showers the heats continued after lunch, until in mid-afternoon the scoreboard showed as in Top shows the opening scene as the O.0.D. addresses the skippers. Next, Elsa and Ivy obligingly pose with the dressed Birkenhead flagpole, and below J. T. Manley receives the trophy from the hands of Mrs. Taylor. Gentleman just visible is J. A. Bruce. Bottom shows Eros with J. T. Manley and J. Lace. Bottom right, Delight and Trude show how the weather lew up for the finals TROPHY 1954 VIC SMEED the photograph. The six finalists commenced the sail-off in a really stiff blow; Delight dropped to 3rd suit, Curlew II to 2nd, and two of the others lowered their rig slightly. As the heats drew on, Eros (entered by a secretarial slip as Cholina) unobtrusively commenced to pile up points so that it came as quite a surprise to many onlookers who had fancied Black Hawk or the Nocturne design Wolverine to find that, with only two re-sails in hand, Eros was the only one within striking distance of Black Hawk. The critical re-sail a beat between these two boats was accordingly started in a tense atmosphere, despite the heavy shower just passing over. The wind was such that Eros, in the windward berth, held little advantage and, in fact, the boats started practically straight up the lake. Nine feet from the finishing line Black Hawk was leading by four or five feet, but came gradually into the side. Skipper Roy Bradley poled her off in an attempt to gye over the line, but she hesitated on the turn and Eros, sailing straight down, had her bow inches across the line as Black Hawk reached it. Although a big disappointment for Bradley, the win was well-deserved, especially when one considers Eros’ circumstances. She is the first boat built to a design which was laid down by Dick Priest during a series of lectures to the Birkenhead club in 1951, and the design set out to illustrate how to get the maximum out of rating rules. Owner J. T. Manley had finished her only a week previously, and apart from one unproductive wetting in a fitful breeze From the top: Black Hawk and Miranda away in the morning’s sunny spell; the scoreboard at the close of the eliminating rounds (note Eros entered as Cholina); the very first board of the day, between Wylo and Barcrisan, and, bottom, one of the last, between Wolverine and Delight. Bottom left, Eros and Black Hawk battle out the penultimate board Left to right: “Reelew” and “Marianne” on their second board, in very light air; 685 “Olive” the only hard chine boat in the race; Roy Bradley discusses the weather while adjusting “Black Hawk,” with “Eros” and “Olive” in the foreground; ““Trude” and “Ivy” on their way up, one with spinnaker and one without, earlier in the week, this was her first time in the water. Mr. Manley was unfortunately not well enough to skipper her himself, and even mating proved too much for him, so she was sailed virtually single-handed by Jack Lace, who only took up the hobby in 1950. The design is rather a departure from normal Marblehead practice, and, in fact, quite dissimilar in many ways from what might be expected from Priest’s board. Noticeable is the seal-flipper keel and forward-raked rudder, and closer examination shows very flared vee bow sections running into a considerable tumblehome extended right through to the transom. With 2 in. for’ard overhang and lin. aft the 47 in. L.W.L. is well under many contemporary 50/800s. However, a very long bearing surface is apparent on heeling. Other main dimensions are L.O.A. 50 in., max. beam 11 in., L.W.L. beam 10.6, displacement 22 lbs. Altogether we would count this an exceptionally handsome craft, in or out of the water, and we are pleased to be able to tell readers that the design will become available in our Plans Service in a few weeks’ time. After a briet spell for mopping-up operations, etc., in the club-house, the Trophy and other prizes were presented by Mrs. Taylor and the competitors packed away their boats for the long trip home. Seven clubs—Birkenhead. Bolton, Bury, Doncaster, Fleetwood, Morecambe, and North Liverpool—were represented. and of the half-dozen or so new boats some were so recent that they still awaited registration numbers. All voted the meeting extremely enjoyable. Our thanks are due to the organisation undertaken by Mr. J. A. Bruce, with the assistance of Mr. A. Howarth and others, to O.0.D. Priest and Assistant O.0.D. Wally Jones, plus the judges, starters, recorders, and stewards, and last—but never least—to the Birkenhead ladies for the provision of the excellent lunch and the never-ending stream of tea and cakes. Finalists. Eros … .. Black Hawk… Wolverine Curlew Il Trude Delight J.T. Manley … R. Bradley G. Stobbs J. Palin J. Blundell G. Redfern N. Liverpool… Bolton … “ae Doncaster Morecambe Fleetwood Bury… gs … er Se 19 Rta || 14 aes ULMIE points 3s 5% ,, Tay gs 3 gns. prize for longest distance travelled —J. S. Reeves, Doncaster. Left to right: ‘Curlew Il’’ and “Trude” away in one of the later rounds—note change in the weather; “Wolverine” bowls along on the run; “Eros” displays her shapely hull, and is seen a action on her maiden board, against “Olive” on the extreme right 376 ’ THE SECOND OF H. B. TUCKER’S “WIND” SERIES, WE CONFIDENTLY EXPECT THIS MARBLEHEAD TO BE NEW TUCKER 50/800 A REGULAR \ 1955 prove both fast and amenable in all weather. The only “ Duck ” feature retained in the design is the so-called “ Transom Step.” This is really not a step at all, but an Anti-Back-Pressure Rim, which extends the sides and bottom for a short distance abaft the boat’s actual transom. Its action is to ventilate the after side of the transom, thereby cutting the capillary attraction of the yacht’s skin, and reducing to She Settee L.W.L. 5 475 DRAUGHT 10.5 SPACED SECTIONS Nini fr Vy WINDSONG (2) cnentD ow SPACED SPACED DISPLACEMENT SAIL AREA a ,, 0.75 ,, 0.75 ,, 5.0 ,, , 4 oe:,.2 Ate. Weights oz 12 sere water dis- ise WITH HATCH | 0 PAINT AND VARNISH | 0 | 51, elaeaa \ X SS 5 L wos ar ty aoe ig “=a fig = in Oe Pra eae = : cl 3 Bomaae Sig: feb pe = Sere Ps \ee MN \ SS Tams oe mss RGAE ae oe 7 won pans con muweer pipe ne 4 SA, WL i2 os poli Sams oun SD las 9 eee cae ae a eer ee TD ihr wu? : wie : ne ees be x L | NI = woe e ay DECK HESS fre and 2 A wou te wus a. pressure i in. an 3 T 4 gael 22 Ib. 4 oz. 800 square sy MODEL _MAGER PLANS Sem wos IG (fy See back ‘ i Woo H.B. TUCKER 10.5 BUTTOCKS the device is an adaptation of the step overlap sometime s used on hydroplanes. I do not know who first used . SOt MAX. BEAM… . minimum ‘M-CLABS YACHT Dimensions L.O.A. a turbance, otherwise inevitable astern of a squaresterned craft. It has proved most successful, and boats fitted with it leave a remarkably clean wake, provided they are otherwise well designed. This is very well balanced, her C.B. moving a bare 1/20 in. aft at 20°angle of heel. Every care has been taken to eliminate all possible steering vices, and to reduce all resistances to forward motion, while taking every advantage of the latitude given under this Rating Rule. RIG IN S WINPSONG was designed in response to requests for a design to the M-Class that is not a “ Duck.” The “ Ducks” sail extremely well, but admittedly, are unusual in appearance, and some people dislike them for that reason. If the reader asks me whether Windsong would beat a “Duck,” my reply is that it would largely depend on the respective skippers. Windsong should W.L.s WINNER 2 cam orci —( ws fk tk BD eS St Gh Wa eae | pues Nes’ wu? wee STEERING GEAR 6 oe FITTINGS 6 TRIMMING BALLAST ute 6 oR 4 his LEAD KEEL… … 14 wae pee wus SIZE REDUCED PLANS SAIL PLAN ea WITH DON HERTS. SERVICE, ROAD, PRICE 38 Post L ae | mS a zt i — I i | = 1 Se CLAREN- b WATFORD, 10/6 Sa ARE AVAILABLE FROM MODEL MAKER PLANS ——— ae ee = fr aes fo FULL tan a Free B 390 JUL complied with), the only thing they have in common is their L.O.A. Restrictions. In the 36-inch Rule, the hull is severely limited in L.O.A., Beam, Depth and Displacement, while Sail Area is unmeasured. In_ the M-Class, the hull has no limitations other than L.O.A., and the Garboard Restriction, but S.A. is this idea on a hydroplane, but I can claim to be the first to adapt this to sailing boats (whether full-size or model). In making this claim, I wish to put on record my indebtedness to Messrs. D. A. Macdonald and G. Hicks who provided two sister boats from the same moulds and carried out extended trials to resricted to 800 sq. in. prove the value of the device. I have given full details of this on the plans as an most powerful hull possible within the imposed limits, and then give the boat every inch of canvas she will carry. In the M-Class, the designer must arrange his permitted 800 sq. in. of sail into the most efficient sail plan-he can devise, and then design a suitable hull to carry it on the permitted 50 in. L.O.A. We all know that the most important factor for speed is sailing length, and it is, therefore, clear that little or none of the L.O.A. can be devoted to over- The easiest way to make the rim is from a strip of brass or copper 3 in. wide. This is let in flush with the yacht’s skin, and as mentioned projects 3 in. abaft the transom. In a planked boat, this will mean using an extra thick transom, or better still, fitting fashion pieces to make the housing for the plank ends. Now let me deal with other points of the design. starting with a slight analysis of what the Rating Rule calls for. Although both the 36-inch Restricted Class and the M-Class (i.e., the boats are limited by a set of Restrictions, and there is no rating formula to be Hence, it will be obvious that in the 36-in., the designer has to get the largest and “ Optional Fitting,’ but I can assure builders that it is worth embodying. The design is drawn as a boat 50.0 in. L.O.A., but if the Rim is to be fitted, the length should be curtailed to 497 in by taking + in. off the transom. The rim projects ? in. abaft the transom, which will then make the total L.O.A. 504 in., thus taking advantage of the } in. tolerance permitted by the Rating Rule. hangs. This often misleads designers into thinking that overhangs can entirely be dispensed with. Let us first consider the bow. Under the old tonnage rules, yachts of the ‘ Cod’s-Head—Mackerel Tail” type were developed with a greatly immersed forefoot. Although very wet, they usually managed to avoid “ pitchpoling ” and running under, but in these boats the saving grace lay in their inefficient gaff rigs of low aspect ratio. To couple a deep forefoot with a modern high Bermuda sail plan is asking for ed e ee e _—_—_—_—_—_—_=_—— 4 Cea ae ia ie, PSR _ Bs \c wu XS CDN pas ee. Sars PIS DIG =a 4 : 95 4 ‘ihhice.c ee SALL__AREA mamean, tt 282 oT +308 ae | aes 7 ee Ee ca ie see 391 Momath 6808 HSK 25S WAT \UPP 4h Ss sur 32 0 6POOT Ay WOUEL: MAKER) trouble. Hence, we sometimes see a deep forefoot coupled with laborious effort to give the bows reserve buoyancy. How much simpler and better is it to give a very short forward overhang and lift the forefoot clear of the water! When we are dealing with the stern, we know that all square-stern boats drag a wave behind them, and are slowed by back-pressure. If the bottom of the transom is lifted just clear of the water, the evil is greatly mitigated, but this entails a very short overhang aft. If this is given, and the “ Transom Step” fitted, all trouble in this respect is overcome, and the boat’s speed benefits accordingly. rudder, and also to careful elimination of all possible vices in the hull, the yacht will be extremely light on her helm and require to be steered small. In consequence, she will require only small angles of helm, but due to the rudder being well clear of the hull and the boat’s speed, these small angles of helm will require to be applied firmly. In consequence, a linkage ratio of 2:1 or even 23:1 should be provided for on the vane gear. The lines in general are sleek and easy, so she should be an easy boat to build by any method, including planking and double skin. The W.L.’s and Buttocks are spaced } in. apart, so if she is being built bread-and-butter, either on the W.L.’s or Buttocks, wood } in. finished can be used. The Sections It will be seen that Windsong has 14 in. overhang at each end, making her L.W.L. 47.5 in. Yet nothing is lost in sailing length, since the boat. will settle in the water immediately she starts to move, and lengthen to the full. are spaced 5 in. apart (except for one intermediate Section right forward) so if the boat is planked, inter- mediate ribs angle of incidence of the after profile. in carrying the tack of the jib low on the foredeck where it is masked by the side when the boat heels. Likewise, the foot of the mainsail is also fairly high oe AARON the utmost driving power from our limited I have shown a radial jib-club with a “Guy Blogg” pattern fitting. In this the jib-boom gooseneck is mounted on a kingpost, which is stepped on the kelson, and projects about 2 in. above the deck. This permits the use of a kicking strap underneath the boom, and thus controls the after-leach of the sail. while permitting extra flow in the foot as the sheets are started. The point to observe is that the rake of the kingpost must be arranged so that the post points directly at the head of the sail. This prevents the kicking strap become tighter as the boom swings out, and obviates the sail sticking up in light winds. Some model yachtsmen do not like radial jibs but prefer the old-fashioned model yacht pattern. It is my firm conviction that the use of the former, as opposed to the latter, converts the sail from a pressing sail into a lifting sail, and thereby adds about 20% to its pulling power and general efficiency. I have embodied these features in all my designs, including my new 36-inch Ivor Duck design, which has proved decidedly faster than her predecessor Donald Duck. D. A. Macdonald built her under the name of Quacky III and won the Class Championship at Dovercourt with her this year in the boat’s maiden race. It is a very strange thing that all boats designed on these principles, from VH In It will be observed that I have made the foot of the jib more horizontal than usual and lifted the tack accordingly. This rule measures actual S.A.. and not the fore triangle. Hence, there is no sense It should be the designer’s aim to attain his ends by the simplest possible means, rather than eccentricity of line and would-be smartness. To use a cliché, “Art should conceal Art.’ Hence, there are no unusual features in this yacht, though there are one or two details that call for comment. Tank experiments show that while the entry should be rather blunt, the delivery should be as long and easy as possible. It was also found that a square stem has no retarding effect, but rather the contrary, while also effecting an appreciable saving in L.W.L. measurement. Looked at another way, these two features in combination give the effect of a considerably longer sailing length than actually exists. During SORA the main board. plywood. soever is lost in efficiency. ACERS AE RARE between the building bend from side to side. It can with advantage be made from a very light thin sheet of waterproof in apperance is worth the trouble, and nothing what- A-Class to 36-inch, have an exactly similar action and wave throw, and are notably clean through the The fin is practically a parallelogram, and all waterlines in it from top to bottom are exactly similar in shape, so one template could really be used to mark out the lot. I mention this also in case anyone wants to build the fin up from layers of a different thickness, say 1.0 in. The lead is designed to cast a little overweight to give a margin for cleaning up, and also for any necessary adjustment to fure-and-aft balance. The type of skeg and rudder used is extremely simple. The top of the rudder is raked well downward to avoid obstruction to the lee garboard waterstream. This avoids the vice engendered by the “barndoor ” type of rudder which has its top immediately under the yacht’s backbone. Due to her bent in off cut before putting on the garboard strakes. The centreline of the deck is dead straight from Stemhead to transom, and all deckbeams are arcs of the same radius. This not only gives a handsome and “racy” sheerline, but has the additional merit of simplifying construction, as the deck is a simple Hence, if one water. be comes preparation for this, the slots in the keel should be end is to be longer than the other, the counter should be longer than the bow overhang. However, there is no difficulty in making them both equal, and the gain the past two or three years, should ribs when she Windsong’s overhangs are so short as to be hardly worth the name, but it will be observed they are of equal length. No matter whether overhangs are short or long, it is best to make them equal. It has been suggested that the forward overhang should be the longer, presumably because of the relative shapes of bow and stern, but boats gain more sailing length aft than forward as they heel, due in part to the lower I have a preference for metal masts on account of lesser windage, and consequent less disturbance to the mainsail luff. ; Windsong is designed to be at her best in moderate winds, but should be able to give an excellent account of herself in any weather. I, should expect her to be very close-winded, and really go where she is looking. Downwind, her immersed forefoot and buoyant bow should make her plane easily and at a very high speed. Windsong should be a sleek and handsome craft, and I hope she will win many races for those who build her. May I express the hope that some of those who build her will write to me in due course and let me know how she performs. 392 e