| The RCA Engine Story Part 2
Thursday 22nd January 2009
The RCA Engine Story. Part Two By Peter Hogan
The RCA Wasp Motorcycle project, and the final air-cooled engine.
As you know, the air-cooled motor was fully developed as a light car engine, and possessed ideal characteristics for that purpose, however only a single example was ever sold! The car engine was also offered for motorcycle use, even though it lacked the sporting performance that would have made it a much more desirable unit. As Richard Christoforides had little interest in motorcycles at that time, and was anxious to press on with other marine projects, no further development work was done until 1961, when a complete RCA Wasp motorcycle was produced.
The frame geometry of this machine was a close copy of the 203cc M/V Agusta racing motorcycle which my brother had once raced, and naturally it handled like a dream. We made the frame and telescopic forks complete, but the hubs were bought in Italian items, laced to Borani alloy rims. A rubber mounted RCA engine was installed, and after further development on the test bed and road, a balance factor of 60% was adopted.
Externally the engine looked much the same, except that the induction pipes possessed 15 degree of downdraft, were 60mm longer than standard, and were splayed to accommodate completely separate carburetors. The exhaust pipes now incorporated neat integral manifolds where they joined the cylinders. Internally however, the transfer port lower walls had been milled away to shorten the effective length of the passage. A sporty port timing was adopted, based on settings used on the successful hydroplane engine. Maximum speed was 88 MPH still with exceptionally good tractability, a full 10 MPH faster than the Road Test carried out on a Greeves in 1958.
Richard Christoforides had no intention of making motorcycles himself, and he now tried to sell the whole project. To my surprise a wealthy young man responded to the advertisement, and having tested the machine over an extended period, bought the manufacturing rights for £5,000! He had just come into a substantial inheritance, and against the wishes of his financial advisers, proceeded to set himself up as the manufacturer of the Antar motorcycle. We supplied him with the running prototype, and a complete set of components for a second machine that he could use as patterns. He naturally had a full set of drawings too. It was hoped that he would buy lots of engines from us, but alas the whole thing fizzled out and no more was ever heard of him or the machines.
Actually, three sets of components had been made, and the third set I retained for my own use. In 1970 I built the final air-cooled engine No. RC 1211, and installed it in this machine, which was completed to the point where it could (and was) run briefly on the road. It was my intention to then strip it right down for painting and plating, and to register it for my own use, but I never got round to it. It was stored on the roof of the assembly shop of Dolphin Yacht Engines Ltd. and is probably still there!
Such a shame that this final version of a fully sorted RCA motorcycle engine was never submitted for road test.
Another interesting motorcycle project would have resulted from trying one of the water-cooled “Dolphin” cylinder blocks in place of the normal air-cooled component. They were completely interchangeable and ran very quietly. Finally, what would the motorcycle engine have performed like, had it been fitted with cylinders from the hydroplane?
Water Cooled Marine Engines.
The E.L.K. Marine air-cooled outboard project had become bogged down, and Richard offered to design the whole outboard unit for them. He reasoned that if he could get them started, we could supply them with lots of engines, and they would be charged for the design work too! He simply bought an American Westbend 35 outboard and copied it, although the large fan providing cooling air for RC 106, and an original and very handsome professionally made hood, completely changed the appearance of the finished article. Two prototypes were displayed at the Earles Court Boat Show, where orders were accepted! When tried in a boat, the only running example overheated so badly that the cooling fan was enlarged straight away, and was now so big that it must have absorbed several horsepower to drive it! Still the engine overheated. With a water-cooled block fitted, RC 106 ran beautifully, but ELK.Marine would not accept this, and threatened litigation. So ended the E.L.K. project.
Richard now had a complete working outboard on his hands, and he sold the whole project to outboard engine makers, Coventry Apex. They paid for further development work that we carried out on the water, (I learned to water ski behind this boat, it was jolly good!) and also for a pretty restyled hood. They placed an order for 30 engines, and began to manufacture the rest of the outboard ready to receive them. They were having difficulty making the underwater unit, so we made these for them too. Everything was delivered to them in one batch, but they were slow to pay. After waiting for some time, Richard put the Receivers in, and that was the end of Coventry Apex.
DOLPHIN MARK 1 INBOARD. Richards next project was to bolt the underwater unit from the outboard to the bottom of an aluminum plate, and attach the engine to the other side. This produced an Inboard engine, which could be fitted simply by cutting a hole in the bottom of a boat, and bolting it in! A sort of inboard outboard if you like. Steering was by a rudder, incorporated into the baseplate. Richard displayed this himself at the next Boat Show, and accepted orders. When eventually tried in a boat, it proved to be useless. The propeller, now located right under the hull, just kicked away the water, and the boat fell into the hole! Maximum speed fell from 27 mph with the old outboard arrangement, to 14 mph. Furthermore, the rudder just would not turn the boat
DOLPHIN MARK 2 INBOARD. This was exactly the same as the Mark 1, except the engine swiveled and steered the boat just like an outboard. The rudder was discarded, and the whole unit was mounted much further back. This arrangement worked well, although speed was well down on the outboard. The engine was specially tuned to offset this.
DOLPHIN MARK 3 INBOARD. This was the same as the Mark 2, except that the engine was de rated from an optimistic 25 BHP to 15 BHP by fitting a tiny single Amal carburetor in place of the two normal Monoblocs. This motor proved to be ideal in river cruisers as it took up so little room, was easy to install, and was very quiet. A large number of these were produced, and most finished up on the Thames.
Whilst all this had been going on, it had become clear to me that RCA Ltd was more of a hobby to Richard, than a business. He undoubtedly had independent means, and was content just to amuse himself. As far as I know, he never drew a salary from the company.
The Hoganrood Hydroplane had by now won its two National Championships in the capable hands of Mike Crisp. Mike then sold the outfit, and purchased a ten-ton ocean racing yacht called Tudor Rose. As I owned and raced a National Enterprise dinghy at that time, and so had a good knowledge of sailing, he invited me to become a member of his crew and compete in the RORC and East Anglian Offshore Races the following season.
We had a good crew, and soon we were all trying to alter and improve Tudor Rose, just as we had done with the hydroplane. Tudor Rose was fitted with an 8BHP Stuart Turner engine, which weighed 365 lbs. Since the hydroplane engine had weighed about 45 lbs., and developed 45 BHP, it was suggested that I might produce a lighter engine for Tudor Rose, and save perhaps 300 lbs. at a stroke. This would of course, dramatically improve the sailing qualities.
As another Private Venture, I purchased one of the outboard engines that had been built for Coventry Apex, from the liquidation stock. This was then fitted with a reversing Dynastart, a Jabsco water pump and suitable mounting feet. The very small carburetor and inlet manifold from the Mark 3, was used together with a fabricated exhaust system. The Stuart Turner engine was removed, but the tail shaft and propeller were left in place. The new engine was installed much lower in the hull, directly under the tail shaft, which was connected to the engine by a pair of pulleys and multi v belts, providing a suitable gear reduction ratio. An outrigger bearing was fitted to the overhanging end of the tail shaft, to resist the side loads from the belts, and to transmit the propeller thrust to the hull. The whole lot weighed about 65 lbs., and drove the boat perfectly. It also provided astern operation, by stopping and restarting the engine backwards, and also charged the batteries. Starting was instantaneous, even though the engine had to start against the propeller load, as a 24-volt system was employed. No gearbox lever or linkage was required in the cockpit, just the ignition switch and a Bowden cable operated throttle control.
Mike was tickled pink, and would demonstrate his new engine to all and sundry. Soon RCA were getting inquiries for these engines, and Richard was obliged to introduce a proper yacht auxiliary engine into the range. This became known as the Dolphin Mark 4 Yacht Auxiliary Engine.
Since it was clearly not practical to offer a belt driven unit, a 2 to 1 reduction gearbox was incorporated, with an output shaft that could absorb the propeller thrust. To improve smoothness, the engine was rubber mounted, and this in turn required that universal joints be included in the drive shaft. Provision was made for hand starting in an emergency, but otherwise it was the same as Mikes. It all worked beautifully, and the orders came flooding in. One order was for 50 engines on condition that they incorporated some form of decoupler, so that battery charging could be achieved, with a stationary propeller. Richard designed a sliding spline decoupler, which was fitted in place of the rigid coupling. Whilst it certainly did the job, the loose fitting splines rattled and clattered appallingly, and ruined the sweet and quiet running of this batch of fifty motors. Acknowledging his mistake, he replaced the decoupler with a centrifugal clutch. This was a great idea, but as the clutch only ran at half engine speed, it had to be of considerable size. Now it was possible to start up in neutral, when the engine would happily charge the battery. Opening the throttle would increase the RPM, and the clutch would engage, and away you would go. In practice it worked well, except that when idling the gears tended to clatter. This model became the Mark 5 Dolphin Yacht Auxiliary, and we could not make them fast enough!
Just when we seemed to be on to a financial winner (for yacht owners we found, were prepared to pay handsomely for a good product!), Benny Rood announced that he was moving to Northampton. He had been producing parts for Keith Duckworth for some time, and had now been offered a Directorship in Cosworths. He was to control the machine shops in the new factory, and the first job was to build the DFV Grand Prix engine! He invited me to join him, and run the new test house, but I chose to stay with RCA! Before he left I received some intensive coaching from him, and could soon machine all the major parts to a high standard.
In 1964, RCA came close to being awarding a lucrative government contract. We were approached by MEXE the military experimental establishment, who let us know that The British Aircraft Corporation, Guided Missiles Division, had a need for an engine, and that ours, in their opinion, would probably fit the bill. They required an engine that would develop 18 BHP at 4,500 RPM and would run flat out and non-stop for 200 hours without attention. If we were prepared to submit an engine for test purposes and it met their requirements, we could expect to receive an order for thousands of units! I was required to sign the Official Secrets Act which forbids me to disclose the intended use of the engine, and so can say no more on the subject, however we prepared a water cooled, single carburetor engine that they tested for power output. This was satisfactory, as it developed 18.45 BHP with full silencing to inlet and exhaust. They then went on to attempt the endurance run, but after 99 hours, one of the contact breaker arms fell to pieces, stopping the motor. New sets of breakers were fitted, and the run was completed without further problems. They stripped the engine and found it to be in good order, and suggested that we re submitted the engine with modified breakers, when they would then repeat the run. We took the motor back to the factory where we discarded the Siba contact breaker set, and bored out the housing to accept the Lucas equivalent, as used on the Triumph Speed Twin motorcycle engine. This time the engine ran through without a hitch! We found, to our amusement that the MEXE people had assumed that we had submitted a new engine for the second test, and they had run it in before commencing the run. They were impressed that internally it was still perfect after some 430 hours of testing, and said the contract was ours! Unfortunately, we had a General Election at that point, and the new Government promptly cancelled many outstanding projects, including this one!
I had learned quite a bit about yachts by now, for example that a yacht has a natural maximum speed (this is one and a half times the square root of the water line, measured in feet). For example, a 16-foot waterline boat cannot exceed 6 knots, but a 25-foot water line vessel will do 7.5 knots on the same power, despite its extra size! (All other things being equal, of course!) As a yacht has a beautiful slippery shape, surprisingly little power will drive it at its natural maximum speed, and our reduction geared engine, despite its small size, was excessively powerful for many installations.
A direct drive motor was constructed and tried to see if a smaller, high-speed propeller would do the job adequately, and despite being less efficient at turning horsepower into thrust, it did the job very well. It also had the undoubted advantage that its small size created much less drag when the yacht was sailing, and this feature proved to be very popular with keen yachtsmen! By pure chance we had stumbled on a niche market that ideally suited our motor, and a Direct Drive Dolphin Mark 7 model was constructed and was pressed into production.
A single batch of 50 had been made, when Richard Christoforides sadly died from a heart attack
1967. R.C A. Ltd. is restructured and expanded.
Control of the company now passed to Benjamin Christoforides, who wished to expand the operation, starting by quadrupling the production!
To achieve this output, a much larger, 24 engine stand assembly shop was constructed, and additional machinery installed in the space formerly used for assembly. The office and stores were relocated into an adjacent building. More staff were hired, mostly machinists, for I wished to continue with the assembling, as far as possible. Handling all the parts enabled me to act as a form of quality controller.
The sole product was to be the direct drive Mark 7 Dolphin Yacht Auxiliary Engine, (with a complete installation kit) but it was a visibly different unit to those made before Richards death.
In an attempt to enhance the smooth running characteristics, three experimental engines were constructed before the new design was finalized. One had a large central flywheel, as used on Scott motorcycles, which should behave like a gyroscope and stabilize the engine. Another had the cylinder bore centres reduced from the standard four inches, down to only three, and so reduce the rocking couple. In the third prototype, the weight of the reciprocating parts was reduced to the absolute minimum, with the balance factor suitably corrected.
Since, with water cooling, there is no advantage in using exhaust ports at the ends of the cylinder block, the new cylinder had orthodox exhaust ports on the sides, where they mated up with a much neater manifold. The Siamesed inlet ports, as used on the very first air cooled prototype, were reinstated. The crankshaft was also identical to the low compression prototype version, containing plain flat flywheel discs, and pressed in shafts. A Jabsco water pump was belt driven from the output end of the crankshaft, which also carried a smaller, six-inch diameter centrifugal clutch assembly. This incorporated screws that could be used to lock the drive in neutral. An emergency cord start facility was included. This version was smaller, lighter and very much neater than the earlier engines. It was also both easier and cheaper to make! Despite de-rating, it still developed an excessive 12.7 BHP. As anticipated, vibration was a shade higher, because the mass had been reduced, but with rubber mountings this was not a problem.
Demand for this version of the Dolphin was very high, and although the re-arranged factory worked well and our production target was soon achieved, delivery times still lengthened to 15 months!
Refined jigs, fixtures and patterns had all contributed to the improved output, but it was the assembling of engines 24 at a time, and the machining of components in much larger batches, that raised efficiency most noticeably. Extreme amounts of overtime were still necessary from the staff, whilst I only left the factory to sleep and eat!
By 1971, just when I was expecting to ease up and resume a more normal life pattern now that everything was running smoothly, the bombshell fell! The Harlesden factory was about to be demolished as part of a local council development plan, and we would have to uproot and start again elsewhere!
Benjamin Christoforides seemed delighted with this news which offered the chance for further expansion at the expense of the council, for they were obliged to re-house us! They offered us a superb new factory plus financial assistance if we were prepared to re-locate to Bodmin in Cornwall, a London overspill area they wished to promote! I was far from keen on the idea, acutely aware as I was that Benjamin, (despite his 70% shareholding in the company, to my 30%) had never attended the old factory on a regular basis due to his other business interests! This had unexpectedly saddled me with the day to day running of the company, which combined with other unavoidable distractions meant that I could do little real engineering work during normal working hours. Only after the staff had departed for the night, could the more demanding work receive my undivided attention! During that stressful period if I was awake I was working, and after three years of it, I was exhausted. To lose our efficient workshops and trained staff, and start all over again was, in my opinion, calamitous!
Benjie however was keen to take advantage of this opportunity and to make a new life in Cornwall with his brand new wife, assuring me that he would, in future, devote his time exclusively to running and promoting the expanded RCA business. The bank was quite willing to provide the frighteningly large overdraft facility that such a move would require, providing that the Directors sign Joint and Several Guarantee documents accepting personal (and individual) liability for all debts. I was not willing to do this, so my directorship was transferred to his new wife and I continued as Works Manager whilst retaining technical control.
The move to Bodmin was planned with military precision, but unfortunately the new factory was still just a shell when the contents of the Harlesden factory arrived. With no internal walls, no light, power or heating or phone, and only the short working hours of January days, progress was initially very slow. Nevertheless a beautiful factory was eventually completed and production was resumed on 14th April 1972.
John Chapman, the machine shop foreman and his cousin David Chapman, my assistant on engine assembly, had both agreed to relocate to Bodmin, but Benjamins arrival was postponed for about six months.
By the end of the year the training of new staff was complete. With Benjamin running the office, the factory was now in full swing with production running about 50% up on our previous best. David and I found the new (30 engine stand) assembly shop a delightful place to work, but John Chapman’s wife disliked Bodmin, and in July 1974, persuaded him to quit and return home. The replacement machine shop foreman was a disaster! He was accustomed to operate only the finest machinery (so he said) and I caught him red-handedly, dropping lumps of scrap metal into the gearbox of our elderly Ward 3A capstan lathe so it would break down and be replaced with a new machine!
After this incident, I reluctantly took on the running of the machine shop again, for I knew that I could trust my protegee, David, to maintain standards in the assembly shop without me. I took on one final task as well, by introducing a massive stock control Pin Board (with 220 columns!) to ensure the assembly line, after several predictable delays, never ran short of components again.
Solutions were also required to all the usual production problems. When Siba discontinued our Dynastart but offered to supply an identical item, save for different mounting faces and taper, all RCA components in front of the crankcase required complete revision! Siba next discontinued the electric solenoids, and the use of alternative Instanta units required a fully revised electrical panel too! Finally Instanta went bust, so we made our own RCA relays after that!
With the future supply of Dynastarts in doubt, a new Mark VIII Dolphin prototype was constructed, employing an RCA modified reversible Lucas M3 12v starter, which was engaged only when required by an electro-magnetic clutch. The Lucas crankshaft mounted alternator was neatly tucked away inside the flywheel. This all worked perfectly and was very extensively tested. A revised Dolphin Saildrive unit was also produced, using again the 2 to1 geared underwater unit from our old Mark 3, but employing the current much neater, short manifold cylinder block. Neither of these units made it into production, but a small reduction gearbox that enabled the standard direct drive engine to power yachts up to 10 Tons, was successfully produced.
During this period the factory prospered, but although RCA became the principal manufacturer of yacht auxiliary engines in the UK, it was still barely able to keep pace with the demand.
1978 The Demise of RCA Ltd.
Sales continued to remain buoyant for many years, but eventually they took an unexpected downturn. A large Japanese manufacturer of industrial engines was marketing an excellent small marine diesel engine in the UK. These could be used as a yacht auxiliary engine, because they possessed most of the virtues that had made the Dolphin attractive. I quickly studied the design, and came to the conclusion that the YANMAR was a very fine little engine. Remarkably small and light for a diesel, and although only a single cylinder engine, it was fitted with special balancing shafts which made it acceptably smooth running. The result was a very attractive and extremely well priced product. The discounts that were given to boat builders were astonishing, we could never match them! In addition, on top of every other incentive, a further 10% promotional discount was allowed! We clearly could never compete with a giant company, who we later discovered, manufactured a new engine every 50 seconds, right round the clock!
Our customers were apologetic, but were unable to use our engines any more. Sales dwindled to a trickle, and even though we quickly offered a separate 2 to 1 reduction Dolphin gearbox, so the Mark 7 could power the larger yachts, it was to no avail. In September 1978 the Receivers were called in, and R. Christoforides and Associates Ltd. went into Voluntary Liquidation.
In Part 3, read how the company was rescued from the liquidators, and reformed as Dolphin Yacht Engine Ltd.
|
Mark 4 Prototype
PLEASE ALSO SEE PHOTOGRAPHS OF THE PRODUCTION PROCESS IN THE GALLERY SECTION. YOU WILL HAVE TO PRESS THE NEXT BUTTON A COUPLE OF TIMES TO REACH THEM!
|
