Slot car racing

 

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Slot car racing

  I started in 1963, after purchasing a Scalextric car set, and got the bug to compete.

 I found a commercial track in Rockdale, a suburb of Sydney; this was about two kilometres from home.

The Scalextric cars being unsuitable for the big track I bought a Monogram chassis which came with a 1/32nd model and replacing the plastic wheels and chassis with an assembled brass running a Mabuchi 16 motor. Using solid rubber tyres it at least made it around the track albeit slowly, but for the plastic Scalextric track, it was too fast.

 Next car was a 1/24th scale Tomichi with a solid plastic moulded body, spring-loaded brass chassis with a Mabuchi 36 motor, about double the size and a little faster.

 Lloyd had painted the track with high traction paint, and all hell would break loose if Lloyd the owner caught the whiff of methyl salicylate (Dencorub) which softened the rubber to give better traction. He was annoyed as it also stripped the paint off the track and gummed up the newer sponge tyres. As it wrecked the tyres very quickly, I never bothered because the advantage wasn’t that good as it quickly formed a hard skin which then had to be sanded off.

 They invented high hysteresis rubber which was able to grip glass, yes good grip but everyone now knows it as superball rubber. Not a good combo when a tyre hits a bump.

  A Cox 1/32nd GT40 with a die-cast magnesium chassis and a Tomichi Porsche 906 with die-cast sprung chassis with ‘side-winder’ mounted 26d proved much faster, you could also use a heavier slower 36D motor.

 About this time, I discovered the delights of rewinding your motors to get better performance. This modification involved replacing the standard wire with thicker, i.e. 26 to 18 gauge, and 120 turns down to 70 turns; (thicker than 16g and less than 40 turns gives you a red-hot cracker with no brakes.)

 This modification converted it to a less than 6 volt instead of 12 volts; thus increasing the revs per minutes from 14 thousand to 25 thousand r.p.m. and decreasing the lap time by several seconds.

 Still not competitive I bought a ‘La Cucaracha’ (the cockroach) with a pivoting, pressed aluminium chassis, inline 26d driving the rear wheels with the front holding the guide, the outer half held a lightweight clear plastic body painted on the inside, the body secured with wire clips. Much better than the screws in the hard plastic posts, these tended to break-off in collisions. To compete in club events, I replaced the original body with a somewhat scale ‘Lexan’ McLaren M6.

 Over several weeks the motor was rewound, wider micro-cell tyres fitted to wider rims, smaller free running wheels to the front; and the underside filed to give clearance as required. Neil had a similar one; this had the same treatment, though with experience was somewhat less cobbled looking.

 I hadn’t realised at the time, my experimental rewinding for the Rockdale track had inbuilt superior brakes compared to other rewinds. The usual hot winds were notorious for accelerating very fast but not braking as well for corners.

 The reason for the weak brakes at Rockdale was due to the warning light to tell you if the hand control was incorrectly connected, this feature introduced an unwanted resistance into the dynamic braking circuit. By having the best brakes on the track was an advantage until someone fixed the problem by putting a jumper lead across the light bulb. At other tracks and after I used my jumper lead, I returned to the best brakes, a bit rough on the crown gears.

  Neil and I dropped into the Cessnock track on the way to Tuncurry one time just in time to watch the running of a local sprint race. We waited until the race finished and had a run afterwards. We had watched all these hot cars having much trouble with overrunning corners due to poor brakes. We got on, then matched the local lap record and locking up the back wheels on every corner. Neil and I just cruised around making the local hot shoes drop their jaws; hopefully, they were glad we hadn’t arrived earlier.

  That day we went onto Tuncurry and showed the locals how the ‘big city’ boys could drive. While I was there, I rewound my cousins' Aston Martin DB4 car motors; they ended up getting banned because they would catch up from behind and knock the other cars off the track. I happened to have all my gear with me on a 2-week holiday spent with my grandfather.

  Back at Rockdale, Lloyd decided that as everyone was using micro-cell tyres and ‘goop’, he would paint the track with engine oil so at least that it would be consistent. Not a good idea, very messy and required regular cleaning of the contact braid so that you could get power to the motor.

  I was now back to square one, clean everything off and repaint with gloss paint. The design of micro-cell tyres required gloss paint with a trace of oil turning the tiny bubbles into suction caps. The use of either STP or Wynn’s Charge engine oil additives made for interesting effects if you use too pure a mix. Wheel standing or instant stop if you put it on the track before a corner as the Charge oil had the consistency of cold honey and the STP somewhat like golden syrup. The trick was to use a bit less, 25% with engine oil then heat the mixture to about 100 degrees Fahrenheit then cool before bottling it. The commercial premix was about $6 for a thumb-size bottle (a day’s pay).

  At about this time Jim Donald and I were moving up the ranks of the local hot thumbs, I with my much-modified kits and Jim with his scratch-built chassis and wheels.

  Jim was a machinist and had a micro lathe where he made his wheels complete with set screw wheels and drill-blank axles. This axle was before it became essential to have these; his chassis were real works of art, even down to matching the lengths of the motor wires and laying them neatly along with the chassis. I had one of his cars for a long time, a sprint car with the centre chassis carved from a single piece of spring steel.

  The Cucaracha chassis had a hook and rubber band on the guide to centre it when replacing on track; Jim achieved the same effect by taking care with the wire length. Rubber bands broke or unhooked at the most inopportune times with the resultant rubber jamming under the car.

  Jim was more interested in competing with the sprint races while I preferred the longer endurance events as I got more bang for my buck. With sprints, one bad moment meant that the day was over, during enduros, a slow period could be caught up at a later period when the other drivers ran into trouble.

  However, when I was invited to make up the numbers with the club team for an 8-hour race at Ramsgate; we ran the team car which was woefully obsolete, the team ran last.

 A little disappointed we adjourned back to the Rockdale track. My car had gained an extra modification as the car was left upside down on the back seat reforming the plastic body perfectly around the chassis and tyres. Is that serendipity or what?

Steve Hutchinson, who was a professional driver for the winning Team Testor, had followed us and was surprised when we both ran rings around him. We now had a home turf advantage and knew about the brake light jumper lead. He asked, “How come you didn’t use one of those for the race?”

  Good question, after that we started to do just that and gave the top teams a bit of curry. Our club team leaders returned to their true scale cars, very nice looking, don't handle and disaster if you crash.

  Because the lap record was regularly getting a battering; Lloyd set up races with different restrictions, such as standard motors, tyre width or sedans, etcetera. Within a week, Jim or I would be going just as fast much to Lloyd’s frustration. His standard requirement was a maximum of 2 amperes draw on his chassis dyno. My rewinds were among the few that could meet this restriction.

  One of my standard motor chassis was a special cut down to nothing, 1/32nd open-wheel Lotus F1, the 13uo motor replaced by a 16d with the front end screwed to the cap and the rear wheel bracket soldered to the can. The body just clipped over the motor, with 2 to 1 gearing it flew; wide micro-cells on the back and little independent wheels with o-rings for front tyres ensured that it took the corners.

  After reading the blurb, I tried the special motor that Testor was selling, making my first scratch-built chassis for it. This car was made out of thin aluminium alloy sheet (I was an aircraft apprentice), with mounting nuts and bearings ‘araldited’ into position. As the performance of the motor was less than advertised, I tried to become competitive by ‘white-anting’ the chassis until it looked more like Swiss cheese; had moderate success though I had adverse criticism for what looked a bit dodgy.

  I have recently found out that Ian Bannister had passed away, I was in a sprint race against him once and had to apologise when I knocked him off a couple of times. It was my home track, and I knew I didn’t have to back off in that particular corner, and the other was the early braking manoeuvre. I forget who won, but I believe I was right up there with the top boys. The visiting competitors were touted as the pinnacle of state of the art, I wasn’t overly impressed, mainly because of the previous paragraph, but later I found that the motor design had been a lemon, it wasn’t the be-all and end-all of the progress in motor design.

 The Rockdale track was 220 feet long with eight lanes, powered by 12 volts. Starting from the driver's position, turn one largest radius flat out, bottom straight into the tightest corner. If you brake a bit early, the car following will receive a boost and overshoot the corner. The next set was a short straight into a flat left-hander, uphill run past Lloyds counter, where if you judge it right you can overtake in the air, left hand flat out into main straight and the start/finish line, into a nearly flat out left, the track then descends into a slalom. I could time it to straight line the slalom and overtake my right-hand neighbour on HIS RIGHT before re-entering my slot. I would gain 3 feet in the manoeuvre and another couple as he picked his jaw up; last corner second tightest to the right to enter drivers straight.

  Note; overdoing the jump puts you into the window, or if open, oops you are a floor up. Missing the slalom timing leaves you in a pile on turn six where it is difficult because the marshal masks the bottom straight. If you make sure when you use the braking trick, that the subject car is on the outside doesn’t take you with him.

  I would rate it a driver’s track being fast enough to be interesting, requiring a good handling car and still be challenging for a driver.

  The longest track that I have raced on was the Yagoona track 240 feet; they used track patches to calculate that the current sprint cars were doing 45 M.P.H. (80 k). It was all on one level with just a standard loop to provide the figure 8 effect.

  With marshalling, the best techniques are:-

1. Don’t come off.

2. If you do be patient.

3. Thank the marshal, and next time he may put you on first.

4. Make your car easy to see, identify the front end, ensure that the guide always is aligned and doesn’t jam sideways.

  I built my first piano wire and brass chassis for the standard motor competition. It was a copy of the Cox Cucaracha with a 26d side-winder motor and an STP Indianapolis body (wedge) to make a minimal open-wheeler; very competitive. I fitted side deflector bars to prevent a rocket launch when back wheels entangle, these modelled after the speedway cars which have serious problems with that. On a speedway track, you have a combined 1200 + hp suddenly redirected to lift your car to the skies, and it is just as spectacular for slot cars; hurling your pride and joy 3 metres at an angle over the side and off the track.

  Motors such as the Champion series had larger copper heat sinks, bushes with ‘pig-tail wires’ and heavier springs, all of which allowed hotter winds and therefore speeds. Cheaper mods to the Mabuchi motors included using 36D heat sinks, brushes and springs. Shimming magnets, fitting of stronger aftermarket magnets, balancing armatures gave me a lot of things to fiddle with or spend money.

  I was involved in dozens of enduros ranging from one man 2 hours and team events 4 to 12 hours, and Two 24 hour races, the first at Miranda and the second at G&D Parramatta, in the last our team came in second both times.

  During the Miranda race, the number one song at the time was MacArthur Park, so that makes it 1968. I don’t remember much about it except that I slept in on Monday and called in absent to work, this being the second last straw with Qantas.

  In the second race, the team comprised Jim Donald, the car builder, Kevin Colbran the transport and modest lead thumb, Ray Murray and protégée Kim Axton. Around 8 PM, I left to take Kim home as he was 14 y.o and needed his beauty sleep. I returned to Parramatta to find the car languishing in the last place. Ray had cleaned the motor brushes with lighter fluid then put it back on the track before it was dry. POOF, up it went requiring a total rebuild.

  What can you do, I settled down ran a 1-hour record, and then followed up with another hour record averaging the current single sprint lap record; this took our car from last to first in 2 hours against the best racers in NSW. Despite being a little nervous about leaving, I drove back to Rockdale to pick up Kim; back to the track, found the two slower drivers had slipped back in the placing; Jim and I finished the race returning the car to finish in 2nd place.

  Over the years, I made a variety of angle as well as side-winders; when flexible side flaps became the go, sometimes sprung or not; I used that design as well. One car I fitted with a chassis-mounted wing directly pinned to the rear chassis ahead of the rear wheels. As an aircraft tech, I set this at the correct angle to provide downforce with minimum drag; it worked quite well.

   I was commissioned to build several chassis for a merchant sailor of the perimeter ultra-light design; I wasn’t too keen as I preferred to complete the car and track test before delivery. This test would usually expose misalignment and other faults; when I commented that one of Steve Hutchinson’s chassis was a bit stiff out of the packet, I was challenged by the sailor who was back in town stating mine were wonky; another reason that I hadn’t built any more of them. Of course, he wanted it light, rugged and not too attractive to others; I think he said that someone still knocked them off.

  My last serious race was in Dandenong Victoria when I was invited to compete in a sprint race. As I only had the one car, this being an endurance side-winder I wasn’t expecting to be competitive.

   Still, I qualified very consistently around the 50th qualifying spot, thus landing me with the new boys in the slowest repechage. Of course, qualifying required running a single car on full power which made the sprint cars go their fastest, whereas my endurance car when it didn’t wheel stand and had to restart, was still going normal speed.

  During the repechage series I had no problem winning each race until the semi-final where I finished 3rd qualifying for the final, as the lower voltage allowed me to average the same speed as I did in qualifying; together with my experience to avoid accidents. On the way, I had picked up my host for the previous night with him following through to the final.

Now that I was with the specialist sprint drivers I was still able to finish 7th and received the 'good sport' ribbon the organisers usually award this to the one who marshals the best but because I was on the track the whole day I didn’t do any marshalling except during qualifying. The total races for the day were 14 of which, I won the 12 repechage heats.

Over time, the competitive cars became more expensive, to overcome this to allow wider participation, classes were introduced to level out the playing field, group 12, 16 and 20 originally based on the American standard of dollar value. For the keenest, this meant having to buy or build several cars to compete or go to group 7 with the big boys where money was no object. The cars that I bought for Toowoomba were approximately Group 20 and cost $100.

  The cars were put aside because I had started competing in motorcar and motorcycle sports. The tracks at Rockdale and HMAS Albatross had shut down as well as the one in Tuncurry where my parents now lived.

  This lack meant that my career was at a halt until I had moved to Toowoomba after retiring from the army. I found the local track, and I took the kids there to show off the cars. Wendy had struck up a conversation with the owner casually mentioning that I had been a racer, back in Sydney. The owner turned out to be Kim Axton, who was building tracks in Toowoomba. By the time I had caught up with the Goss, the kids had wrecked my three remaining cars.

  The new business meant I had no time to become involved again; I had to put it on the back burner until several years later when I located the track now run by Hooky.

  Bringing grandchildren, this time, I resurrected my old cars and bought new ones. With a couple of sessions, I felt I was back to my old form, middle quick and steady.

  The new wing cars left me cold as these meant that the driver spent hours preparing car and track, then thumb down and hold it there; perhaps lifting off once a lap for the tight corner at the end of the second straight and I could see no driver skill required. They average a real speed of approximately 175 KPH (110 mph). The lap record at Hornsby is .5 seconds or 7200 laps per hour.

  I recently watched a video clip about the Aussie world champion Wayne Bramble; the track video looked like a stop-frame special effect with the cars just blurring around the track. When interviewed, he said the motor cost $700 and was good for about five minutes the time for one bracket.

  After a marital problem and being uneconomical, Hooky closed the track, and that is now the situation.

I am currently in ‘retirement’.

 

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