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Last updated
23 May 2010
Afiliated to:
BRCA No. 5251
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Race dates
Handling tips 6 P's How to be a champ Easy Guide to rechargeable batteries
Our Rules Their Rules
Racers rides
Beginners Guide
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Hints and Tips New Drivers. Please do not be put off the first time you try your new car. Most of our drivers have been in this sport for some while and do seem to make driving a radio control car look so easy. OK, its not quite as easy as it looks but with a bit of practice you could be up there with the best. Remember this. Everyone felt just like you are now when they first started. We have all been there. When I first started, I very nearly gave up, but with some encouragement from other drivers, I carried on and now I am glad that I did. I am certainly not the best but I really enjoy the sport and hope that you will too.
The six P's
Perfect
Handling Tips. Under the rear ball joint put about 1mm of washers underneath lifting the pod giving the car a little bit of anti-squat. (Allegedly) Try it and let me know if it works for you. Put some threaded turnbuckles on using Schumacher ball joints, or whatever equivalent you may have handy, and give the car neutral toe in to 1degree toe-out - more toe out gives more steering. Modified track rod sets are available from trackside shop. Change the kit servo saver for the small Kimborough type and 'hey presto' the steering returns to neutral every time! Replace the front springs on the pivot pin with several little 'O' rings / rubber fuel line / wire insulation which will remove the front suspension but give a little play - but this will stop the front end snatching the rear end around. The rear suspension should be set while batteries are in the car (at race weight), so that the weight of the car will compress the spring by about 0.5 to 1mm, this is very soft but it'll improve rear end grip. But loosen the two screws which compress the 'O' ring on the shaft, these are best used only as a guide for the rear pod and not for damping action. if you do this the car will feel 'bouncy' on the bench but will be very good on the track. Speed Tips: Make sure to run a decent cable from speed control to the motor - preferably an Electronic Speed Control which is suited to 4 cell racing (some are not!). M.Tronics Eco 20 (£26.99) or Eco 27 (£20.99) Specially made for Mardave by M'tronics, no delay Speedos available from trackside spares The best motor to use is an HPI Saturn 20turn, or RS540SH which is also BRCA legal, (in case you care!). Try the 46 tooth spur gear rather than the 50 tooth gear supplied with the kit, this will speed the car up with faster acceleration, doing this gives more room for a bigger pinion, so experiment with how you want the car to perform. When the motor is brand new, attach it to some wires directly to a fully charged battery with correct polarity so it is revving forwards. While running at full speed, dangle the motor into some clear hot water (not the batteries) and let it run in the water for up to 1minute. this will bed the brushes in so there is more brush contact on the commutator. After doing this, fix the motor in the car to hold it still, remove the wheel on the motor side and don't put a pinion on. Attach a dremel to the armature (where the pinion is usually fitted) and run the dremel to spin the motor (at fastest setting) in the opposite direction to what it would spin when driving the car. Let the Dremel do this for up to 15 minutes. This will wear the brushes in a way which will advance the motor timing slightly - enough to make a difference. To clean the motor, between every run. Spray motor spray onto a cotton bud and push the cotton bud onto the comm. and spin the rear axle to spin the motor. Repeat this until the cotton bud comes out of the motor clean - this can take up 7 cotton buds. Between meetings, take the motor out of the car and run in hot and slightly soapy (washing up liquid) water for about 10-30 seconds, and then use motor spray to blast the soap suds off. Lubricate the bushes. Check the axle bearings between meetings, use motor spray to clean them and keep them lightly oiled so not to encourage dirt to stick to them. Once they become gritty they are hard to make free again, remove 1 or both shields and clean again - this will make them as free as they'll ever be - but they get dirty quicker. Tyres: If you prefer foam use soft or medium on rear and medium or hard on front. Use super glue or double sided tape to stick on wheels. when using double sided tape, fit tape to wheel first then wet with soapy water. wet tyre also then slide into place on wheel and leave to dry. Body Shells: Paint ABS shells on the outside, using normal car paint available from such as Halfords. One spray can will easily do three shells. First wash the shell in soapy water to remove any dust, dirt and greasy fingerprints. Dry with a clean cloth or paper towel. (Do not use a cloth that has been used for car polishing as this will leave silicone deposits behind with disastrous results) Shake paint can thoroughly and then shake for another minute. this is best chance of a good colour match. It is also best if paint and body shell are warm. Spray first coat on very lightly. This will give a rough surface to which the next coat will grip and be less likely to run, but don't go mad, it will still run if you put on too much. Third coat should just about be enough to cover well, spray evenly till you see a nice shine, then leave, don't be tempted to just give it one more spray. You should now have a super shiny new shell. If not try another coat. If you can't get a nice shine, use a tin of spray lacquer as your top coat, but be careful, this runs easier than paint. Once paint has dried for at least a day you can polish it with car polish for an even better shine. Car polish is also good for removing minor racing scuffs, keeping your new shell nice for that little bit longer.
Electronic speed controller An electronic speed controller (ESC or speedo) will probably be a future purchase and well worth having if you buy an electric (battery) powered car as they offer many advantages over a mechanical speed controller such as... greater reliability, more speed, longer run-times plus they make a car smoother and easier to drive. They also eliminate the need for a throttle servo and a separate receiver battery pack as they power the receiver from the supply from the main drive battery pack.
How to Be a World Champion R/C Racer These
excuses are an excellent way of showing your fellow drivers you really are
the Dogs B****cks at this hobby and with more luck you really could be
world champion.
Here are a few to justify a jump start:-
The Easy Guide to Rechargeable Batteries: In an effort to take away the science from what is in fact quite complex technology we will liken the rechargeable battery to a bucket! Sounds crazy? Well maybe, but read on and you will see….. A rechargeable battery is just a storage device, it stores electrical charge, once that energy is used up it can be refilled again and so on. Just like a bucket can be filled with water again and again. However, to make the example a bit more realistic, the bucket has a hole in it, so as we are filling it up water is leaking out all the time, and so as we slowly pour water into the bucket it will leak away, meaning that we may need to pour 12 litres of water into a 10 litre bucket before it reaches the brim. In the same way, it takes more energy to charge a battery than it will actually store. Remember the hole in the bucket? Well once its full, the hole is still there and so the bucket will slowly empty, in the same way a rechargeable battery will slowly lose its charge. So what do all the numbers mean? The first figure that you will be given is the “Capacity” usually expressed in “mAh” meaning milli-Ampere hours. This is basically the amount of current the battery will give multiplied by the number of hours that it will give it for, so obviously a bigger number means that the battery will last longer. So from the following table you can see how many hours a 2700mAh battery would in theory last.
This all seems very simple, however it doesn’t quite work this way. The battery is less efficient when larger currents are being drawn from it
So our “2700mAh” battery will last longer than expected if it is used in a device which takes little current, but with a device using a lot of current it will not last as long as expected. Generally battery manufacturers will give the capacity based on “0.2C discharge” This means at a discharge of 2/10 its rated capacity i.e. 540mA for a 2700mAh battery, There are some cheap batteries where the manufacturer gives the capacity based on a much slower rate of discharge, and so the capacity seems very good, like with the example above, at a discharge current of 100mA the battery would seem to have the capacity of 3000mAh. At this moment (Feb 2007) there are no manufacturers producing 2800mAh or 3000mAh AA size rechargeable batteries, with a 0.2C discharge rate, the technology simply hasn’t got there yet, although there are plenty who have products advertised as “2800mAh” or higher. Be very wary of both these manufacturers and the companies who sell them. If they are being dishonest in this way about the capacity of the battery, you must ask what else are they being dishonest about. Sanyo are regarded as the world leaders in the development of this type of rechargeable battery, so if they cannot produce a battery with a capacity greater than 2700mAh you can be totally sure that no-one else can. What about the Voltage? This is the one area that rechargeable batteries do differ from their non-rechargeable cousins. The standard throw-away batteries (Zinc-carbon, zinc-chloride, alkaline etc) have a typical voltage of 1.5V whereas rechargeable (NiCd / NiMH) batteries are given as 1.2V These voltages are governed by the laws of physics / chemistry for the different technologies and so the voltages are the same for all manufacturers, although some claim 1.25V this is true for all rechargeables immediately they are charged, but once in use this quickly falls to 1.2V. The vast majority of devices this voltage difference does not make any difference. Take a look at the following graph, which shows how the voltage of a set of Duracell alkaline batteries changed over time when used in a digital camera. The graph also shows the way the voltage of a set of rechargeable Vapex 2700mAh batteries changed in exactly the same application. As you can see the voltage of the Duracell alkaline batteries steadily dropped as they were used, but the voltage of the Vapex rechargeables remained fairly constant until they were almost exhausted. What is interesting to see is that the voltage of the alkaline batteries when they are around half used is the same as that of the rechargeables, so rather than being a different voltage, they are the same as the voltage of a part used alkaline. What about other types of rechargeable battery, such as rechargeable alkaline, or rechargeable lithium? Rechargeable alkaline batteries will give you the same voltage as a standard alkaline battery, but that is about all they have going for them. They are expensive, Lithium rechargeable batteries are better, but still there are drawbacks to their use in place of standard AA or AAA batteries:- They are expensive That being said, lithium battery technology is advancing fast and so the future will probably see more & more devices being designed to be powered by lithium batteries
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