R/C racing cars tips and tricks.

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Spanish version

This page is derived from the spanish original version. It has started as a translation done automatically, that, being a so long page, will be improved manually with time. Sorry for the incorrections appearing on it, till the manual translation process finishes. Hopefully, it is readable.

In general, the tricks appearing here have a general character, with some of the following purposes:

And now, let us mention some tricks:

Suspensions alignment Protection of shock absorbers
Ammeter to verify linkage of servo Filling shock absorbers
How to tune a receiver Draining bubbles in shock absorbers
Tin to measure head clearance Fastening the piston in shock absorbers
Uses of the thermo-retractable cover Assembly of shock absorbers
An  spit on time is a victory Balance of shock absorbers
To tin-plate steel cable To determine point of anchorage of shock absorbers
Clips of body unlooseable Measuring the displacement of the shock absorber.
Silicone tubing for extraction and insertion of glow plugs Protector of glasses of palier
Silicone tubing as top or spring Increasing duration of glasses
For fragile rims Measuring angles
Fixing and taking off wheels Aprons
Uniform pressure in the tank Double ramming intake in the deposit
Carbureting by blowing Greater duration of clutch shoes
Drill after front bearing of motor Protection of crown
How to measure speed Diverse forms of the package of batteries
Use of decreasing chronometer Use of portable reproducer MP3
In order to avoid differential blockage Optimization of the re-fuelling
Protection of bodies paint To avoid to spill mixture in re-fuelling
Blind drills Minimización of the consumption
Use of photo film cases High speed re-fuelling
Adaptation to the duration of the neutral pulse Optimization of the linkage
Smoothing knuckles Tape uses velcro
Filter on the refuelling bottle Fine adjustment of stabilizer bars
Protective capacitor on the starter switch Strips of cable joint like prisoners
Protection of exhaust pipe General protection of the car before blows
Mark of tire hardness Coefficient of friction of the tire
Transmitter: replace dry batteries with rechargeable batteries Chispómetro of emergency
Smoothing suspension wishbones Suitable use of the bank screw
Adjustment of hardness of wharves Termoconductora silicone use
Initial engine smoothing How to avoid the mud in races All Land
Charging batteries on ice Subjection of the escape elbow
Difficult starting: spark plug or refrigeration. Prisoners
To assure the feeding "transponders" personal (PT's). Windscreens of microphone on the air cleaner
Cutting bodies  

Aligner of suspensions

Construction
Use

So that the car is controlable, it goes straight and store not to go of side when accelerating, the distribution of weights has to be same to left and the right, and the wheels have to have equal support; all it can be verified rigorously with two or four balances. First it can be verified with balance, and the second raising alternatively the wheels, or better with the simple device of the figure, that can become detachable and adaptable to cars of any scale, sliding the tube.

The rod must be rigid. The tube can be of aluminum or brass. The bearings will have inner diameter the one of the rod, and outside the one of the interior of the tube. Once constructed, without supporting the car, we must verify that the movable part is in balance (with wood blocks will be able to be balanced with facility).

The shared in common log to the tube (part fixes) and the front part of this one will lean in a horizontal surface, which can be verified with the level on the mentioned log. In order to use it, we will locate the car as it is indicated, we will press the suspensions and we will look for that the bubble is left horizontal. The level must be light, either will locate it in both sides of the movable part, looking for symmetrical readings, or will balance it with a equipolente weight. The front train must have the straight direction, and the car must symmetrically locate with respect to tube and rod (it is due to mark with labeller in the logs the symmetrical position of chassis and wheels, or to locate several marks symmetrical making a scale).

The back and front part is recommendable to free the adjustment in both axes supporting in the fixed part from the chassis in the fixed log of the device, and the train opposed in the movable part. The stabilizer bars must be annulled during these adjustments.

If we used stabilizer bars, the adjustment will be successive:

A possible modification of the invention is two equal logs in the fixed part with the drill for the tube in its superior part, leaving hollow for the movable log, and simplifying the support of the set. This is advantageous if the car to fit is great (Great Scale), because everything could lean in the ground. With a good construction of the set it can even be done without the level. The lateral Vista of the invention would be:

Previously to this adjustment we can verify:


Amperimeter to verify linkage.

Sometimes, inadvertently we can have forced the route of the servo one:

Indirectly, we can verify it inserting an ammeter of DC, that agrees that it is of needle (nondigital), when coming out of the battery, and observing the consumption:

  • In movement absence, the consumption must be almost null.
  • When moving the servo one, must show a current tip, and reached its position the consumption must stop if it does not have to overcome obstacle some.
  • On guard of braking, it is normal that there is current consumption, because the brake will be against to the movement of the servo one.
  • Particularly, the servo one of direction does not have to indicate consumption in the extreme positions, with raised front wheels.
  • We will move a servo one to the time, to free the measurement.

As it is seen in the figure, he is recommendable to use a cable servo cable stretcher of whose positive thread will be cut to insert the ammeter, which will facilitate his connection.

According to size and pair of the servo one, thus it will be the consumption. The servo ones of medium size (1/8, 5 to 8 Kg.cm) normally have maximum consumptions between 0,5 and 1 ampere. The used ones in Great Scale, quite greater. According to the maximum consumption, thus it will be the ammeter:

We will fix a connector of servo male and another female to the poles of the ammeter, trimming the positive of a prolongador cable length of servo. The positive of exit of battery (female) will go to the male of the prolongador, and there to the positive of the ammeter; in the negative of this one we will locate the female connector of the prolongador.

If we cause that the servo one acts against something fixed (without wharf), we will verify a great passage of current, that will imply that the life of the servo one is certainly brief.

Also, we will observe if the current of the servo one is in all its stable route. Abrupt variations of the same one can indicate servo in badly been.


How to tune a receiver.

This one method adecúa to the classic receivers Futaba, but its foundation adecúa to many others.

It is possible to locate in the receiver the demodulated signal of the train of pulses. With this method it is tried to heighten this signal, which we will obtain with a voltmeter of continuous (to go on insurance, it must be of needle). The negative will be located on mass, and the positive in a Futaba receiver, according to indicates the figure, in the sideburn of raised resistance, approximately where it is indicated.

The quartz of the receiver must be the one that normally we use, or the one of intermediate value between which we take to race. Giving feeding to the receiver, with the transmitter extinguished, we will see a tension of 3V. We will move away the transmitter moderately, and we will ignite it; the tension will lower to a value between 0,5 and 1V. Then, with useful available in stores of handle electronics of plastic and a small end of screwdriver, we will be fitting the coils in the order indicated in the figure, until obtaining a minimum reading. The great sensitivity in the coils of high frequency (4 and 5), but in those of loss will not notice (1, 2 and 3).

This method is based on which the indicated resistance belongs to the circuit of a transistor, in whose collector is the train of pulses, and that leads when there is pulse. The more under it is the mean level of the signal, the more will be made lead to the transistor and better it will be the syntony.

Nótese that a coil will belong to the circuit of oscillation of the quartz (nearest him), and will not take part in the syntony.

The variation of the signal must be according to is described; if it is not thus, we are not in the suitable point of measurement, or the method is not applicable. It is possible that in other receivers the signal we locate it in the emitter of a transistor, with which the variation of the signal will be the opposite (minimum to dull transmitter and Maxima to optimal syntony).

To the used voltmeter him we can hook electronics clamps, and have it like a factory instrument more.

This method does not serve to change of band the receiver (it requires to change components), but for adjustments, as to change of band from 72 to 75 the other way around MHz or.

If we observed in the receiver a subject coil with glue in its part superior to the neighboring components, agrees that we improve the subjection with glue of two components: to the being the coil a heavy component, is possible that a sideburn by the vibration of march is broken (the manufacturer already knows it, but much in holding it does not take pains).


Tin to measure head clearance.

In the motors of explosion of metanol, it is known that the height of camera with piston o'clock superior dead (PMS) depends on the percentage of nitrometano of the fuel; it can vary of 0,3 to 0,6 mm for nitro between 10% and 25%, and greater to greater atmospheric pressure (as at the level of the sea). Of factory, normally the height of camera adjusts to the competition, reason why it can be impossible to carburet a motor as it leaves the box with nitro little.

The percentage of nitro to use will force to choose a spark plug of "hot" thermal degree (fine filament for little nitro, normally indicated like R4-R5) to "cold" (heavy filament for much nitro, normally indicated like R6-R8).

A form easy to measure the height with mounted motor is by means of tin to weld of 1 mm: introducing it with taken care of by the spark plug hole, being the mounted motor, we will move the clutch steering wheel until noticing that tin begins to be compressed, and we will turn that one passing the PMS. Later, we will measure tin.

This method usually gives 0,05 mm of excess, since tin recovers its thickness very slightly. The adjustment takes control of washers of 0,05 or 1 mm in thickness, of better aluminum or of copper, because he is better heat conductor.


Uses of the thermus-retractable cover.

The thermus-retractable cover has many uses in Automodelismo: to prepare packages of batteries, to repair cables, to protect connections, etc.

The cable that leaves a package of batteries is put under a use in that tends to break itself, or to become hardened the plastic that surrounds copper threads. If we surrounded all he by thermus-retractable cover, from the interior of the package to the outside (8-10 cm of cover) it will be left prote'ge' much more.

It agrees that the cover is entered completely in the package.

Hot air pistols exist to contract the cover, but a hair dryer will serve to us perfectly.


Lapo on time is a victory.

It is very important to control the temperature of the explosion motors, specially the used ones in 1/8 and 1/10, and summer. It is necessary to consider that comes from Italy or Japan, countries of much more smooth temperature that in Spain. And if of winter to summer there is a jump of temperature of 30 degrees, we can wait for that same jump in the temperature of the motor.

The permissible temperature in shortened stock must be of 110 to 130 degrees, depending on the motor and the external temperature.

The disipadora head has fins of form varied according to the manufacturer. It is necessary to consider:

Usually it is used a measurer of temperature by infrared in the zone of spark plug, with the advantage of being instantaneous. Also, it is of frequent use a measurer by thermocouple, fixed permanently to some screw of butt of the motor.

If we do not have anything of this, we will resort to lapo in the shortened stock, and will control the speed whereupon it boils. If it disappears in few seconds, probably the temperature is excessive.


To tin-plate steel cable.

In Great Scale usually it is used steel cable in cover to transmit the movement of the servo ones; it agrees to introduce fat in the cover.

The cable usually is of bicycle, reason why it will have a head in an end. The fixation of the other end usually is by prisoner, which usually damages the cable. A form to avoid it is to tin-plate the zone of the prisoner; one will become by means of a powerful soldering iron.


Clips of body imperdibles.

The continuous loss of clips of body can be avoided fixing them with thread to fish, that will tie to the paper clip, and it will pay attention to the body with a small drill (0,5-1 mm), and making a knot in the end of the thread.

Same operative to by hand have the paper clip of transponder.


Silicone tubular powder for extraction and insertion of spark plugs.

The spark plug used in motors of metanol, when being inside the disipadora head, usually is of difficult manipulation. A small tubular powder piece silicone of the employee in the admission or ramming intake allows a perfect subjection of most of spark plugs, as much to extract it as to center it in its insertion.

If the spark plug had the excessively fine point of subjection, we can insert silicone in brass tube, to reduce its inner diameter.


Silicone tubular powder like top or wharf.

Small silicone pieces very well a wharf is emulated. The more long it is the piece, the more smooth will be his soft effect.

Also, we can construct a top for linkage of servo, that it avoids that this one is forced in its route.

Another use can be to reinforce a conventional wharf, introducing tubular powder by its interior.


For fragile rims.

If we observed that the rims of the car tend to break themselves with moderate blows, we can increase its flexibility boiling them. A pot with water to pressure will be used (yes, the one to make cocidito Madrilenian), and after two hours boiling we will notice as the flexibility has increased.

This trick can go united to the one to take off wheels, explained next.


Sticking and taking off wheels.

Beating and taking off wheels suppose a headache for many, and as it shows this paradox goes. Many pilots use rims and tires stuck in factory.

In little demanding modalities, taking off the tire if on the rim can be avoided we put tape to pack or similar, and on her we stuck the tire, but we will have to verify if this serves to us or no.

The wheels type rubber usually stick with cianocrilato. It can resort to Loctite 420, of the very low very penetrating viscosity and, that can be applied by outside rim and tire. Loctite 409 also is recommendable. The wheels type foam have appropriate products, but a general solution is to use contact tail: a layer is applied to both surfaces, it is let dry minutes, and they are united.

The cianocrilato beats almost instantaneously, reason why previously we will have to introduce tire (and filling, if it is the case) in wheel. And eye to its handling: to several automodelistas a drop to the eye has jumped them, is worth the redundancy. Since it jumps easily to the clothes, it agrees to use old clothes during his use.

It is necessary to avoid the centrifugalization of the filling. According to the in question modality we can from surrounding the filling with tape to pack or American, or to make a perfect patch of the same one to the rim with tail by contact, with the method indicated before:

If we make a small drill in the rim, we will facilitate the exit of the excess of inner air, particularly in All Land.

It can happen that the tire is taken off, but we see a layer of the same one still stuck the rim; the tire literally "has been taken". If the rim has a rim to embrace the tire, we can resort to apply the cianocrilato by all the faces of this rim.

To put stuffed tire and in rim sometimes is complicated. A can resort:

When beating a pair of tires with track, we must make sure that in the pair of wheels the disposition of the track leaves a symmetrical wheel of the other.

If they are not united of by pneumatic himself and rim, we can resort to bridles. In Great Scale he is very useful to have great clips, uniting two to include the circumference of the wheel.

The faying surfaces must be clean. Often in wheels type rubber the surface is observed brilliant; a slight sandpapering agrees, or to use a cianocrilato activator. In any case the patch process is long and must take control of care, to avoid that the wheels are taken off in race.

If one is wheels of foam in track cars, after sticking them agrees to turn them to his optimal diameter (neither very great, nor very small), as well as to eliminate eccentricities, and to clear edges external and internal.

In order to take off them, a furnace has been used: the heat will take off them. He is more comfortable, and advisable, because it increases the flexibility of the rim, to boil the whole wheel during at least two hours in pot to pressure (the one to make cocidito Madrilenian). And he is much more comfortable to submerge, using a great container type "taper-ware", the wheels in a dissolvent, during a sufficient number (36 to 48) of hours:

We can, to take off tire and to make flexible rim, to use a combined method:


Uniform pressure in the deposit.

In the motors of metanol it is practically general that the deposit takes a ramming intake from the escape. In the branch pipe a drill practices, it is threaded, and a ramming intake pays attention, generally of brass, that is united to the deposit with silicone tubular powder. If this ramming intake has sharpened edges, is possible that it breaks the end of the tubular powder, point that is due to verify periodically.

It is known that to full deposit the pressure in the fuel taking is the one that sends the pipe plus the one of the fuel column, but to empty deposit it will be only the shipment by the pipe, therefore smaller, which can vary the carburetion. A simple tube, ideally of brass, from the superior part of the deposit to the inferior one, where the tubular powder of the pressure will pay attention, will maintain the pressure uniforms while the deposit lasts. This is known in Physics like Bottle of Boyle.

The ideal will be that the tube is inserted taking advantage of the ramming intake the deposit, if this one is vertical. If no, as it happens when the taking is in the filling mouth, we have to worsen the talent, fixing a tube to L, or equipolente solution.

In any case, the watertightness of the deposit is due to verify, if it is necessary disassembling it, draining it, covering a taking, submerging it in water, and blowing by the other taking.


Double ramming intake in the deposit.

Some deposits of track cars prevén two ramming intakes in the cork, the one in each side, so that the one is used that is in the inner side in most of curves, blinding other.

One better solution is to take the pressure with a taking in T, so that in curve, when plugging itself an entrance by the centrifugalization of the mixture, the other is frees. The ramming intake from the branch pipe similarly is reconciled with tubular powder from silicone to the central section of the T, connecting the other two to the takings in the cork.

The T can be found like accessory of gardening, or one can be constructed welding brass tube.


Carbureting by blow.

In principle, a new motor of metanol comes to us simply mounted by the manufacturer, reason why:

The shavings will be eliminated disassembling it, reviewing specially as much the zone of the case like the one of the cylinder. It has been explained already in a previous trick how to measure the height of camera with tin. These indications of carburetion can be consulted , but a easy method for a approximate carburetion is done with the help of tubular powder of silicone in the taking of mixture, closing needles of loss and discharge so that we always notice passage of air when blowing:

It agrees to line the control of the discharge needle, so that we have reference of its position. Also, we will write down the returns and/or fractions of return that reduce until it closes completely.

Logically, this it is a approximate method. Position to roll the motor for the first time, agrees to open the discharge needle additionally. We will sharpen the carburetion as it is explained in the indications of carburetion; also, a direction on wealth and poverty of the mixture can come from the smoke of the escape:

The diverse sounds of the carburetions can be consulted here poor, rich and correct.

If we observed a strange tendency of the motor to stop itself to the slow motion or when restraining, we must review the clutch.


Drill after front bearing of motor.

There are times in which a loose motor of metanol an excess of oil by the front bearing. This does not have greater importance, but it stains, and it can get to affect the braking if the oil reaches the brakes.

A remedy is to practice a drill in the case behind the front bearing, that communicates this zone with the neck of the carburetor: the mixture passage will suck the leftover oil. This drill must be of not more than 0,5 mm, which requires a special reel.

Nótese that is had to retire the front bearing. The motor will dismount completely, and the end of the case will be put under intense heat (burner, blowpipe), or to the gas fire of the kitchen, which will give off the bearing easily. Another fire source can be a container with alcohol, in which an extended portion of cotton is introduced; the cotton locates itself in a metallic support and it falls in love. The alcohol will burn, and the cotton will suck alcohol to maintain the fire. Nótese that in any fire, the hottest part is its superior end.

In order to mount it, the end of the case will be warmed up again, but while we make the drill we will maintain the bearing in the freezer of the refrigerator of the kitchen, which will reduce its diameter in thousandth. The cold bearing will enter easily by the hot end of the case.

This procedure can be used also to extract and to insert the main bearing, for substitution by breakage or to replace one bearing of metallic cage by another one of phenolic cage; it nótese that the front bearing is of indefinite duration, but not therefore the main bearing, to affect him the explosions of the mixture. In any case, after its insertion the main bearing must be perfectly fixed trim and to the block; if it is not thus, is probable the breakage of the crank.

As it is seen, some elements of the kitchen are very useful in Automodelismo.


In order to measure the speed.

Diverse methods can be tried:


In order to avoid differential blockade.

In some differentials (to see types), particularly in those of conical pinions, usually takes place blockade of the output axes in the housing of the differential, which annuls its effect and makes nervous or unmanageable the car, particularly in situations of little it takes hold where the differential is fundamental. It must to that the lubrication must come from the internal fat, that must have a slight flight by the exit of axes; if dry of fat the differential, or the flight is null, can have blockade. This effect does not occur in the differentials of balls, although these require maintenance, replacing balls and/or tracks as soon as notice irregularities or jumps in the action of the differential (a differential of balls in good state must have a smoothness of operation similar to the one of one of gears).

The situation is worse in the differentials of conical pinions, because the planetary pinion, of greater size, can lean perfectly against the housing of the differential, blocking the exit of fat.

In principle, a periodic lubrication must avoid the blockade, but this usually demands to disassemble and to mount the differential, reason why there are other solutions:


Painting protection of bodies.

If we observed that the wheels leave their mark inside the body, will be signal that a rubbing when acting takes place the suspension, direction, etc, that, besides to damage the painting, will make us waste time. It is necessary to obtain that it does not have marks some trimming the body, raising suspensions, etc.

If some mark is by collapse of the body, we can try to avoid locating it properly a nylon bar.

If some mark is recalcitrant, or by precaution, we can protect the painting with American tape inside the body. These protections them we must also locate in the zones of support of the body to the chassis.


Blind drills

Sometimes we must prolong a drill, or an inner spiral, but it is necessary that the drill is not pasante; for example, to prolong a drill 2 mm in plastic. If we have a vertical drill, possibly already it has the necessary additions to this type of operation.

Of some form a top in the drill is necessary. Collarín with prisoner on the reel can be sufficient, but also we can use a piece of nylon tube similar to the used one in antennas. We will cut the necessary length so that reduced of the length of visible reel after fixing it gives it the total depth of drill that we want, and we will insert it in the reel.


Use of boats of spools of photos

In order to keep small screws, nuts, washers and other spare parts, we can use boats of spools of photos.

As of by himself the interior is not visible, we will make a drawing of its content in the cover.


To adapt itself to the duration of the neutral pulse

When describing the radio equipment, the nominal duration of the neutral pulse has been indicated, which for steering must correspond to go straight, is usually is 1.5 ms, but that varies according to the manufacturer. The range of pulse width sent by the transmitter is from 1 to 2 ms, but it also varies according to the manufacturer and the adjustments that we have done in the transmitter, particularly in digital radios.

Frequently the manufacturers of servo and transmitter are different, so that we do not know the nominal duration of the servo neutral pulse of the servo one and may happen that the transmitter has many different adjustments. The problem is that in the rank of width of pulse sent by the transmitter, we can separate from the rank in which the manufacturer of the servo assures its correct electrical operation, or even can reach some mechanical top on the servo itself. For example, if the neutral pulse is 1.8 ms, possibly the servo is designed electrically for the range of 1.3 ms to 2.3 ms. If the range sent by the transmitter is from 1 to 2 ms (neutral pulse of 1.5 ms), we can operate out of the servo range, and reach a mechanical top, or even the servo may stop working. Even if after a first assembly there is no anomaly, it can happen that in the final transmitter adjustments in track and we depart from the nominal range admitted by the servo.

We can make a first approach supposing that the central width of the pulse corresponds mechanically to servo center, and proceed as follows:

Also, by means of the Emisoro program, we can look for the width of pulse that leaves the servo trim mechanically, that we can consider the duration nominal of the neutral pulse.


Smoothing lozenges.

He is frequent that the lozenges of direction (salvaservos, shipments and manguetas) are hard initially. In order to smooth them one resorts to compress the plastic against the ball, with the help of tiles.


Filter on the refuelling bottle.

If it is wanted to be rigorous with the cleaning of the mixture, we can place a gasoline filter of a 1/1 car in the outlet pipe of the refuelling bottle, fixed with silicone tube.


Protective condenser of starter switch.

Often the switch of the extracting boxes of the motors of metanol is rock (simple metallic lamina) or of low quality. The spark that jumps between contacts when interrupting the current will be destroying these contacts.

Immediately than to weld in parallel a condenser nonpolarized of about 470 nF, when interrupting the current will be no spark (the condenser will be loaded), and the duration of contacts will be indefinite.


Transmitter: replace dry batteries with rechargeable batteries.

If we decided on an economic transmitter, reviewing the page on the radio equipment, we have to try that it has investors of servo at least.

With complete certainty, the transmitter will come prepared for dry batteries (nonreloadable). We can replace the batteries by batteries (reloadable), of the same size and characteristics, in individual its capacity (mAH). In order to optimize its use we can come to two additional operations:


Smoothing suspension wishbones.

With total majority, the suspension trapezes go connections to the chassis with steel pins of 3 or 4 mm. The movement of the trapezes on its pins must be smooth, which we will verify observing if, disassembling cushioning and stabilizer bars, the trapezes fall by their own weight.

If the movement is not smooth, we will have to review the drills in which they go mounted the pins, being able to resort to special reels:

This problem appears particularly in cars All Land, in which the dust and river sand are introduced within the mentioned drills, hardening the free movement of the trapezes, reason why periodically they will be due to disassemble these and to clean to the interior happening the reel.

Also, the anchorages of stabilizer bars must allow the smooth turn of the same ones.


Adjustment of spring hardness.

In general, springs are used in suspension and servos-savers. The force that a spring exerts is directly proportional to its increase in length. The proportionality constant depends on the material, the section of the turn (and therefore of its diameter) and, since it works to sharp tension, of the section turn for a variation in the spring length, or of the number of turns by length unit.

It can that we wish a softer spring. Normally the manufacturer provides springs of different hardness, differentiated by colors. In general, the material will be the same one, and the hardness difference can be noticed measuring the section diameter of the spring wire.

A frequent case can be the need to soften the servo-saver spring. The hardness of this one must so be that it yields acting with the hand with certain force, but not as much as so that the car wanders or it does not go straight; another test can be to move the direction by hand with the radio on, and observing if it moves the servo-saver or the servo (in this case the servo-saver is possibly hard). We must first see if the servo-saver is softened with a slight amount of grease.

Another verification on springs in general, and particularily on the ervo-saver is to see if the turns are too close, and get close when compressing the spring in normal work. It is very rare that this takes place in the suspension springs, but could happen in the servo-saver (where usually are used very short springs), which would indicate a bad design of it.

It must be, therefore, the manufacturer who provides springs of different hardness. If this were not the case and we wished to soften a spring, for example that of the servo-saver, we can use a "dremel", reducing the wire section by means of tungsten bits or the flat face of cut discs. This operation will have two effects:

Reduction of spring section with a "dremel"
With tungsten bit With cut disc

Initial engine smoothing.

In general, a new motor of metanol will be difficult to start. The piston very will be fit to the sleeve, and we will notice that in the first attempts to start it is locked to it. There will be initially hardly no fuel admission, reason why the rubbing between piston and shirt will become in dry. As soon as we notice the look of the piston we must let try the turn of the motor, and desenclavar turning it the inertia steering wheel according to the sense of the needles of the clock (seen front).

Some tricks can help that first starting:

What one is never due to do is to unscrew the spark plug to facilitate the turn of the motor, since then will be no mixture suction.


Charging batteries on ice.

At sight of the embarkation schedules of batteries based on the temperature, as much for NiCd as for NiMH, one concludes that if is loaded in cold it obtains a superior tension slightly. Although the gain by element is small, the gain will be, for example, six times superior in packages of six batteries.

We can introduce the batteries in a plastic stock market, and this one in ice, or in water with ice pieces.


Protection of shock absorbers.

The piston rod of the shock absorber deserves a special care, to avoid loss of inner oil, and so that the duration of the rubber ring is as long as possible. When ounting and disassembling the shock absorber, we possibly need to hold firmly the piston rod; it does not have to be seized directly with tiles, but inserting between piston rod and tiles a sufficient number of layers of paper or cardboard (and that this one does not break when pressing).

It is necessary to consider the microscopic cut which the ring of rubber undergoes when going through the rod end thread in which the lozenge of the shock absorber subjects to the piston rod, reason why we will avoid this step as far as possible, or we will before sprinkle the spiral with a dense oil.

It is easy to protect the piston rod of the dust, and particularly in the back shock absorbers of the cars all land (due to the grit blasting sent from the front wheels), with called water globes "". They have form and size of finger meñique, reason why they are very appropriate for the function. They are in stores of chucherías.

Also, often in the cars all land the front shock absorbers the air has left, and exposed to breakage by shock. A strange odd habit of small the manufacturers to do paragolpes increases the risk. To remake this paragolpes with some supplement can help.


Filling shock absorbers.

Depending on our ability, it can that we do not fill up the shock absorbers optimally, reason why a easy and effective method is suggested here. Provided with the silicone oil of suitable viscosity (centipoises cps), we will come as it follows:

It is possible that when compressing the piston rod penetrates air by the detents if these are in badly been or the oil is very viscous. In this case we can resort to one of these two methods:

In any case, it is important to make sure that the detents and sockets they are in good state, and case of doubt, to replace them. Also, it is important that cushioning and soft they are left balances, which can be verified with this trick.


Draining bubbles of shock absorbers.

They exist receiving for food storage in which it stops it becomes emptiness in its interior. Introducing in cushioning them after filling up them of oil, and making the emptiness, the bubbles will arise.


Subjection of piston in shock absorbers.

Normally, the subjection of the piston of the shock absorber to the piston rod is by grupilla (and-paper clip) or nut (normal or autoblocante). This one last method is not problematic, although it agrees to the smaller opportunity to assure the nut with fijatornillos. Nevertheless, the subjection by grupilla usually is not trustworthy, reason why it agrees to leave to completely stuck piston and grupillas to the piston with cianocrilato.


Assembly of shock absorbers.

It agrees that the piston rod is tight strongly against the anchorage lozenge, not being sufficient to tighten it by hand. But never the piston rod with metallic tool will subject that can damage to him: a cardboard strong, or better an aluminum strip doubled in Or between piston rod and tool will protect, and allow to him to exert force when mounting and to disassemble.

The rubber detents undergo very small cuts when happening through the spiral of the piston rod, reason why a drop of dense oil in the spiral when mounting them is due to use.


Balance of shock absorbers.

He is advisable to verify that the shock absorbers and straight left in both trains are tared the same, as well as its wharves. Facing them and compressing them one against the other we can verify if they move the same. This operation we can do it:


To determine point of anchorage of shock absorbers.

The method that follows, although general, is of greater application in cars all land, in which the damping routes are ample.

Let us suppose the shock absorber anchored in the inferior trapeze in A. We determined the lengths IA (extended) and IA' (compressed) that the shock absorber will have. If we wished the route of trapeze indicated in the figure, the point of anchorage of the shock absorber to the wishbone will be A when the shock absorber it is extended, and A' when the shock absorber is compressed. The point of anchorage of the shock absorber will be the intersection of the arcs of radio IA and center A, and of radio IA' and center A'.

It is possible that the arcs are not cut, since we can have incompatible conditions, because the linear displacement of A (AA') is inferior to the longitude difference of the shock absorber (IA - IA'). In these cases the indicated arcs will not be cut. If IA - IÁ = AA', A, A' and I would be in straight line.

In track cars, the suspension routes much more are reduced, reason why there is more freedom to locate the anchorage point. We will take advantage of more length moved away shock absorber the more is the point of anchorage I of the point of turn of the trapeze Or (in the limit, if the shock absorber were anchored in O, it would not work absolutely). The effect to increase to the displacement varying geometry of anchorage would be approximately equipolente to increase viscosity of the shock absorber oil.

Often the shock absorber not anchor to the inferior trapeze but to the mangueta. The method continues being applicable, but we must simultaneously consider inferior trapeze, superior and mangueta trapeze, and the subsequent parallelogram. In order to come with rigor we would have to come as it follows:

In some cases the complica thing if the disposition of the shock absorbers is not like the indicated one here, as in Great Scale, in which he is frequent to use re-shipments.


Measuring the displacement of the shock absorber.

If we want to see how much the shock absorber in compression in march moves, we can insert in the outer part of the piston rod small collarín done with silicone tubular powder, which we will have to locate next to the body of the shock absorber, being this one extended, before beginning to roll. In addition, said collarín it can smooth an abrupt compression of the shock absorber arriving at top.

Collarín can be done without to disassemble the shock absorber to make the measurement cracking thus construído, and inserting it in the piston rod.


Protector of glasses of palier.

In suspension cars the use of palieres finished in ball with needle of bearings is totally general crossed; the mangueta to the wheel finishes in a grooved glass, with the needle inserted in that groove.

The weather of the glass often the fragiliza, or in an unfortunate landing of wheel the glass is opened.

Often glass protectors commercialize themselves, who usually are small brass tubes. Very easily we can be constructed to our protectors, looking for brass tube, steel or aluminum, of inner diameter the outside of the glass. If it is necessary, we will fix protector to glass with cianocrilato.

It is possible that the needle excels of the glass and does not fit in the interior of the protector, which will do necessary to reduce it slightly.


Increasing duration of glasses.

The transmission to wheel in the cars with suspension is made by:

The bearing needle is fitted in the groove of the glass. When being made in almost the exclusively only felt traction is frequent that forms notches in the glass. Even so, the duration of the glass must be long. If we want to increase the duration still more we can interchange the glass with its symmetrical one (in the other wheel, alongside opposed of the differential, etc): the notch will form in the faces nondamaged of the groove of the glass.


Measuring angles.

If we do not have an appropriate goniometer, we can use the mathematical trick to measure the angle through its tangent. In practical terms:

Displacement according to angle
Angle Tangent 50 mm 100 mm
1 0,017 0,87 1,75
2 0,035 1,75 3,49
3 0,052 2,62 5,24
4 0,070 3,50 6,99
5 0,087 4,37 8,75

Aprons.

In cars of All Land, he is very advisable that we prolong the chassis fixing to its lateral trimmed aprons of plastic material, which they fill up the zones between chassis and body, and that will greatly avoid the accumulation of dust and mud.

The effectiveness of this measurement will be seen according to the smaller amount of dust than we see accumulated in the interior of the car.

These aprons, and if it is precise complementing them, must avoid that the grit blasting caused by the front wheels arrives at the piston rod of the back shock absorbers, which would cause a strong erosion to them.


Greater duration of clutch shoes.

The clutch in the thermal motors is of centrifugal mechanism. The classic system is an aluminum steering wheel, with two or more needles of bearing, on which the shoes pivot. These can take some type of wharf, that prevents its centrifugalization to the slow motion. However, there are other types of clutch, adjustable and more trustworthy (clutches type "centax").

If it is observed that the drills in the shoes for their introduction in the needles are opened and get to break themselves, a good protection is brass tube, that takes more in opening itself. Since the needles usually are of 2,5 mm, the protectors will be constructed from brass tube of 2 mm of interior, enlarging it with drill and reels of 2,25 and 2,5 mm.

An alternative is to use cazoletas of fixation of screws of servo including in many of them.

If the shoes stoop to revolutionize plus the motor before it engages the clutch, the friction surface must be done on its interior, respecting.


Protection of crown.

Frequently, the chassis has an opening near the transmission crown, in order that the stones do not get to bar themselves with her. This is effective, but particularly in cars All Land with plastic crown, this one is eroded slowly.

A solution that increases the duration of these plastic crowns is a brass lamina, more or less rectangular, fixed to the chassis to its inferior part by only a side covering the previous opening, so that it prevents the stone entrance but it allows his exit. The free part must, logically, favor the march sense.


Diverse forms of the package of batteries.

The package of batteries must be always introduced in thermus-retractable cover transparency, that we can contract with secapelo. The extreme poles will take to an appropriate female connector : of power in the case of electrical cars, and servo in the rest of the cases.

The connector of the package must so be that it does not expose the contacts, avoiding that can be put in short by contact with external metallic object (female connector).

The connection of elements in series is positive with negative. The positive is due to distinguish associating it to red cable. The elements must be of the same capacity; opposite case can be destroyed by inverse polarization.

In electrical cars the package is of 6 batteries in series, that can be arranged:

In many cases the package we will acquire it already constructed.

In thermal cars the package is of 5 batteries in series, whose normal dispositions are:

(a) (b)

The subjection of the package to the chassis is varied. We can trim a plastic plate and to hold it to the package with American tape, had throughout the heights either the circles the cylinders, and to hold this plate to the chassis according to have anticipated the manufacturer of the same one, or with posts of nylon and clips of body. In (b), if we arrange the batteries in vertical, with three nylon posts and one irons with three drills as a cover, holds to these posts with clips of body, we will have a sufficient subjection of the package, that it will be in addition easy to replace.

In the transmitter a package of 8 batteries of NiCd is common in disposition 2x2x2, although it is possible that the loose batteries are located (not in package, but independent). We can acquire packages of spare part of the manufacturer, or construct them we ourself, acquiring loose batteries:

We can find more details on construction of the package here.


Use of decreasing chronometer.

In the completion of the car, one improves can be translated in tenth by return, and if our sensitivity is not sufficient, it can that nor we notice it. It is necessary to resort to the chronometer, but it can that we are single, or that we do not have any amiable timekeeper.

We can look for a clock or digital chronometer, with the possibility of count down and resumption, and that sounds when happening through zero. Let us suppose that our better time by return is 20"5. We will program the chronometer to that it sounds each 20", and we will pay attention when it sounds in what point of the circuit we are, and we are seeing if we gained meters or we lose them, if a failure or better taking of curve makes us lose or gain centimeters, etc.

He is advisable that the sound takes place in a moved away point of the pódium, so that the noise of the motor does not cover the one of the chronometer. And if it is necessary, we will subject to the chronometer the plus near the possible ear, even choosing our better ear to the frequency in which it sounds the chronometer.

This function is built-in in some transmitters, but the chronometer can be more recommendable by:

If it is not had chronometer with this function, or sordete is a little, it can resort to this metrónomo automodelero free total.


Use of portable reproducer MP3.

Of form similar to the trick previous or metrónomo automodelero free total, we can generate a duration sound the time wished by return, that it includes brief pitido of warning and the rest is silence; this can be generated with publishing programs of sound, that will reproduce in a portable reproducer MP3. For example, for a wished return of 19", we can generate a tone of 400 Hertz and duration 0,2", followed of a 18.8"silence. Later we will be copying the whole wave after itself. When we have ten thus return generated, we will also copy them and stick ten times, having a sound of one hundred returns.

In order to use a portable reproducer MP3, we will record the sound generated in format MP3. The publishing program of sounds must give this possibility us. The earpieces of reproducer MP3 must make possible to us to oir the pitido one in race, even with cars of explosion motor.

On the previous thing we can make variations. For example, if we want additional pitido to half of the 19"return we will generate:

It is possible to also use a portable reproducer of CD, for which we would record the sound generated in a musical CD. The advantage of portatiles reproducers MP3 is its storage in memory "flash", reason why they do not have movable parts.


Optimization of the re-fuelling.

Since it has been indicated, the use of a fast pear in the re-fuelling of explosion cars will make us gain valuable seconds, as well as diminish the number of such.

It is important that the mechanic makes the re-fuelling quickly. Sometimes one resorts in quarter-ton vehicles (1/10) to locate a long bridle in the cork of the deposit, and with which the cork can be raised the car and be opened easily.

Consúltese also the table of times of re-fuelling.


To avoid to spill mixture in re-fuelling.

A piece of gomaespuma can be located in form of rectangle around the neck of the deposit, that gathers any excess of mixture spilled when refuelling. Gomaespuma will be bored so that it pays attention around the neck of the deposit.

This is appropriate for deposits with long neck, and more for track than for all land.


Minimización of the consumption.

In all type of motors, we can reduce fuel consumption with:

In explosion motors, we can reduce the consumption with:

In electrical motors:


High speed re-fuelling.

Besides to use fast pears to be brief the re-fuelling, he is frequent that are the two mechanics who refuel: one raises the car and another one introduces the mixture.

In scale 1/10, given his little weight, usually one arranges a long bridle in the end of the cork of the deposit, so that when throwing of her the deposit is opened. If the car takes tourism body, hiding itself for that reason the deposit, the bridle is almost obligatory. It can be refuelled by the ceiling, or an opened window, using leaned pear. In order to facilitate the visibility of the deposit, in the ceiling it can be let without painting a rectangle, as a solar ceiling.

In the figure, we have a head bridle in the end of the long bridle to facilitate the subjection of the car. If antiupset is protective bar, the bridle can slide leaning in her.

The bridle head will pay attention to the long bridle with a drop of cianocrilato.

It additionally see the table of times of re-fuelling.


Optimization of the linkage

To fit the direction linkage is not problematic, because we will always look for the symmetry. To fit an electronic accelerator in electrical cars either usually is not problematic, and usually becomes in the same accelerator, without touching the transmitter.

The linkage of acelerador/freno in explosion cars is most complicated, and often the little space available in the scales small us will complicará it more. Also, it can have several discs of brake, several handles, brake to the four wheels and using two servo ones, etc.

In the transmitter, the normal adjustment is that control of accelerator in rest corresponds slightly to restrained car with the motor to slow motion, and usually becomes that the route of the control in the transmitter is greater in the part of acceleration that in the one of braking.

Something that we must accept is that in the braking it is going away to continue uselessly pushing the guillotine of the carburetor, which causes a useless increase of consumption of the servo one; we will see next how reduce this impact. Also, since the axis of the servo one always carries out tumbling, the radii according to which the pairs of turn are applied vary continuously; we will see next how take advantage from this fact.

a) Initial adjustment

In a) we have a possible adjustment, that it would correspond to control in rest (car slightly restrained with the motor to slow motion). In order to simplify collarines and wharves have not been drawn that will be necessary. It is a in principle valid adjustment, but that we can optimize, turning slightly to lefts the wheel of brake like in b).

b) Improved adjustment

If our position of rest is b) we obtained:

c) Improved adjustment: total braking position

In c) we have the total braking position, in which we see that one tends to a smaller movement of additional push of the guillotine, and a minor radio in the wheel of the servo one in braking, indeed in Maxima braking, in which is needed to throw with greater force. In the page on the radio equipment, a reference to this same subject can be seen.

d) Improved adjustment: position of total acceleration

In d) we have the position of acceleration to top, where there are to verify that the carburetor is opened completely.

However, after all the previous one we will have to locate wharves and collarines. It is possible that then we find interferences mechanical that they make us modify the adjustment. However, it is possible to be observed that the elements of guide of rods (in gray) have been located to diminish that they can interfere mechanically.

In acceleration, he is recommendable to locate collarín additional that pushes the brake rod, assuring its liberation. In all the movement of the rods we have to verify that they move horizontally, and that the comfort with the guide elements is sufficient.

We can verify the consumption of batteries when fitting the linkage with this trick.


Uses of Velcro tape (Luis Ansoleaga)

The Velcro tape, easily available in haberdasheries, serves to make subjections strong, without damaging elements, and it loosen easily. It is united and it separated so many times as one wants. It can serve to fix the package of batteries or the receiver.

It agrees to arrange uniting it his ends.


Fine adjustment of stabilizer bars

If we even disassembled wheels, shock absorbers and wharves, leaving only the stabilizer bars, it is difficult to see if these press the wheels the same, without tending to press on more than the other. A fine adjustment can become as it follows:

Shock absorbers and wharves with this other trick will be verified, and the car mounted with this one other.


Strips of cable joint like prisoners.

Of the strips of cable joint linkage or steel cable can be extracted its interior, and be used it like prisoners for, with the advantage, in addition, to have double prisoners.

These strips even are in the stores of "Everything to 100".


Protection of exhaust pipe.

In cars of track of explosion motor, the branch pipe is almost always in the left side, and almost without protection some forehead to blows. In curves to left, the pipe is exposed very before a blow inside the curve, in the left side of the car, mainly in circuits to lefts.

A protection similar to the one of the figure, with steel rod of 3 or 4 mm, will save many blows in the pipe and the elbow of escape.
For their subjection the blocks of fixation of the motor can be used properly drilled. The rod will subject to the block with prisoners.

General protection of the car before blows.

In general, our conduction must so be that we do not damage the car, but also to avoid that other us they damage it. An experienced pilot can obtain first, but not always the second, reason why we can implement diverse passive protections, as the one of the pipe of the previous trick.

In cars all land is not frequent to receive a blow of another car, but he is frequent to damage the car in a jump. It is important to verify if paragolpes front sufficiently protects front trapezes and shock absorbers in case of bad fall in a jump.

In track cars the blows are more frequent, and by the high reached speeds they can cause considerable damages. Nótese that the regulation forces to the front use of paragolpes, whose form must so be that the damages of which are diminished is struck by said paragolpes. In some categories espuna is obligatory to complement this paragolpes with one hard, so that he is not paragolpes that strikes directly. Actually, paragolpes front protects sufficiently all the front part of the car.

Formerly importance also to paragolpes back in the track cars was lent, that used to be small paragolpes of nylon or fact with wire. It was sufficient that it excelled of the back part of the chassis to protect in most of the received blows, or by reach of another car, or, if because of I spin a top, we struck the back part with some limit of the circuit. Nevertheless, in the present cars it is done without this protection. Always considering that a back protection does not have to cause damages, we can implement it of several forms:

In cars with explosion motor, we do not have to forget the bar antiupset, that it will not only serve to take hold the car easily, but as protection of butt and air cleanerin case of upset.


Mark of hardness of tires.

The tires that we use must take indicated their hardness in degrees "Shore". For tires of foam track, the manufacturer usually includes adhesives with the indication of the hardness degree, but also we can write on the rim this degree with an indelible labeller.

For rubber tires we can use labellers that are resembled white painting. We can mark to the tires of All Land or Great Scale with these labellers in the internal lateral part of the tire, or in the rim with indelible labeller. These white painting labellers will be the only practitioner for tires of Mini RC; we will mark them in its inner part, dándo for it the return to the tire.


Coefficient of friction of the tire.

The greater or smaller friction of a surface with another one comes dice by its coefficient from friction, which it is pronounced like the tangent of the angle with which a surface begins one to slide on the other, considering surfaces flat. The static coefficient (without relative movement between surfaces) and the dynamic one are distinguished (there is relative movement), being smaller last east, which advises that in braking we must at all costs avoid the blockade of wheels.

If we supported a tire by its lateral face on a flat surface and we inclined it, we can observe the angle in which it begins to slide; its tangent will indicate the friction coefficient to us. Normally, we will surpass clearly 45º (coefficient 1) of inclination.

If we have the stuck tire, in the support face the tire must excel slightly, so that it does not support the rim.

In back tires, to the being the width similar to the diameter, the tire can upset before to slide. In order to avoid it, we can fix a counterbalance momentarily near the support face.

Since the angle can be of difficult measurement, we can measure height h.

Also, we can place simultaneously two tires and compare them: the one that slipping before will be the one of smaller adhesion. To equality of tire mark, the one of greater hardness must slide before (smaller adhesion).

The friction coefficient is specific of both surfaces. Logically, we cannot incline the asphalt of the circuit, nor have it in the factory. The easy thing will be to prepare a smooth wood surface and supposition that if a tire is going to have more adhesion than another one on wood, also will have it on asphalt. However, if we want to come near more to the reality, we can stick a leaf of water sandpaper on wood, and try on her.

All the previous one is applied in smooth tires or with track for asphalt. In all land, they are of greater consideration its tacos; however, the previous thing can serve us to compare used types of rubber (more or less rubber).


Chispómetro of emergency.

Chispómetro can be done simple of emergency connecting to the battery of the car or the starter in series the spark plug (with the suitable hood) and a car light bulb (light corta/larga). The advantage of this assembly is that if there is current passage the light bulb will shine.

Nótese that to the salary two filaments, the resistance of greater to minor will be obtained connecting:


Suitable use of the bank screw.

The bank screw frequently is used to hold pieces and to exert pressure. If we must saw a piece, we will do without difficulty some holding it to it in him. We must acquire one of so large means, avoiding the small ones.

To the steel being, and its jaws of rough completion, we will have almost always to insert a soft material that it avoids to damage the piece that we are going to hold. We can find in the commerce aluminum profiles in L, trim two pieces (holding the profile in the bank screw and using an arc mountain range), and fix them to the jaws with silicone.

For example, to fix the steering wheel of inertia to the crank of the explosion motors, we will come as it follows:


Termoconductora silicone use.

The termoconductora silicone is a white paste that is used in electronics to improve the union of metallic parts as far as the heat dissipation. It is possible to be acquired in commerce of electronic components.

In motors of metanol, the control of the temperature is very important. In order to improve the heat dissipation and to reduce to some degrees the temperature of the motor, we can apply termoconductora silicone in:


How to avoid the mud in races of All Land.

If we are ourselves forced to run in mud, we must come as it follows:


Subjection of the escape elbow.

In the motors of explosion of metanol the escape elbow subjects to the escape of the motor by means of a sleeve of silicone or rubber, that is due to review periodically, and a wharf. He is frequent which by wharf breakage, it wears away or blow loses the subjection, it is given off the branch pipe, it increases the noise and we must stop.

We must use a strong wharf and verify that the drills for their subjection in the escape elbow are not spent.

We can assure this wharf by means of thread brass introduced in its interior and tied to the escape elbow. It will avoid the vibration of the wharf, and if this one breaks in race it even can hold the pipe until end of the same one.


Difficult starting: spark plug or refrigeration.

In motors of metanol, and particularly if it is warm, it can that is difficult their starting. We can suppose that "if it does not start, spark plug", and firstly review chispómetro and spark plug, which must shine generously. If this is correct:

It is possible that in cold the starting is easy, but once warms up perhaps, because the motor has undergone a shutdown, is very difficult the starting. The carburetor must be clean: the dust and the oil can prevent their refrigeration. In order to avoid that the rest of the hot motor to the carburetor we can try to thermally isolate the carburetor of the block:

Nótese that in gasoline motors in Great Scale the carburetor usually is isolated thermally of the block by means of a nonmetallic piece.

On the contrary, when the room temperature is cold (below 15º), it is possible that the starter is not able to move the motor steering wheel, specially in the first starting of you cold winter mornings. Then we can resort to warm up the motor slightly:


Prisoners.

The use of prisoners in collarines, pinions is very common, lozenges, etc, for its fixation to axes or rods. They must pay attention with fijatornillos.

The retained piece can work to traction or rotation against the prisoner. In case of rotation the prisoner must be of flat bottom, and the axis must have reduces to assure the good support and retention between the parts. It is possible that of factory it has not been made said reduces, but it we can easily do with winch or "dremel"; in this last case with end of tungsten or disc of cut handled with care. It reduces must be reduced, in order not to debilitate the piece.

If we see that even so the fixation is not trustworthy, we can resort to a second prisoner mounted to 90º, and its corresponding one reduces in axis.


To assure the feeding "transponders" personal.

According to the specifications of "transponder" personal of AMB (PT), it must make sure at least that its tension of feeding does not lower of 4V, when the car passes over the turn detector. In electrical cars as much the electrical equipment as the PT will be fed from the electronic controller (ESC) and, except for excessive battery salvo, the tension that it provides the ESC must surpass and minimum situation at any moment this 4V. In explosion cars packages of five batteries are used, reason why with the batteries very unloaded (1V) also we will even have amply this 4V minimum.

The problem appears in Mini RC. It is normal to use four batteries, that they will nevertheless give a nominal tension of 4.8V., at the moments of acceleration and braking demands a greater contribution of current from the batteries, which will cause fall of tension of exit in the batteries, and possibly the tension that arrives at the PT is inferior to 4V; we can verify seeing it if when accelerating in emptiness the "LED" of the PT gets to extinguish itself. This is more serious in conditions of unloaded batteries or partially unloaded. We must assure that it does not happen when the car passes over the turn detector, or the return will not be told us.

In order to avoid it:

Before happening through the turn, the condenser will practically have been loaded to the tension of the batteries. When accelerating abruptly, the tension of exit of batteries can lower of 4V, but the condenser will maintain the PT fed, and the diode will avoid that the condenser unloads towards the motor.

We must use a germanium diode (0.Ä) to assure a minimum fall in this diode during the load the condenser. If one is not, can be sufficient a Schottky diode.

For a condenser of 0.047F and a consumption of the 10 PT of mA (0.01A), fixing a unloading of 0.1V to the condenser, it will take place in a time of 0,1 x 0,047/0,01 = 0,47 s: during almost half second the condenser will feed the PT with fall on despicable tension.

In order to verify the assembly:


Windscreens of microphone on the air cleaner.

In explosion cars All Land is very advisable additionally to cover the air cleaner with gomaespuma impregnated also in oil (of ricino, or special for air cleaners), with which we can obtain:

We can construct this cover from gomaespuma in plate. or resorting to windscreens of microphone, locatable in stores of music or electronic components.


Cutting bodies.

The bodies used in automodelismo always are molded in "lexan", a plastic transparency of General very resistant Electric to the blows. They are painted by the interior, preferredly with painting in "spray" for polycarbonate; for better it takes hold, the interior can be sandpapered slightly (surprising, this sandpapering not note).

The color and the decoration will be to our taste, or emulating a car of scale 1/1. In any case it must so be that:

The leftover plastic, including windows if there were them, can stand out by some of the following methods:

When trimming, they do not have to be left points angular. Of American tape small repairs can take control of bodies.


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Last update of this page 30/03/05