Easy Front Spoiler For Pioneer Mustangs and Camaros

by Bob Ward

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The early TransAm rules didn’t allow the cars to use add-on aerodynamic devices such as front and rear spoilers, but as time went on and the rules loosened up just about all of those cars eventually received some aerodynamic upgrades.  You can add a front spoiler to your Pioneer Mustangor Camaro easily and inexpensively by modifying a spoiler from a Scalextric 69 Camaro.  All you have to do to the part to make it fit the Pioneer chassis is grind away some material as shown below so it will fit around the Pioneer car’s guide housing.  The front body posts are the same distance apart on both the Scalextric Camaro and the Pioneer pony cars, so the modified spoiler bolts right on.

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This photo shows the stock spoiler (l.) and the modified one.  I removed the material using a Dremel Moto-tool with a sanding drum.

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With care, you can modify the Scalextric part for a nice, snug fit onto the Pioneer chassis.  Some Pioneer cars have body mounting screws with heads too large to fit inside the spoiler.  If that’s the case with yours just rummage through your junk box for a pair of screws with smaller heads.  They are used on many different cars.

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The spoiler gives your car a different and more aggressive look from all the other Pioneer Mustangs and Camaros  on the track. If you don’t have one in your junk box the spoiler is available in the Scalextric W8813 parts pack.

Low-cost Scratchbuilding and Kitbashing With OEM Parts

by Bob Ward

It usually doesn’t take a new slot car hobbyist long to start thinking about modifying his cars to make them faster and better-handling or building unique cars not available from the manufacturers.

Many of the car-building articles on the Internet tend to steer the reader interested in such projects toward the use of expensive high-end aftermarket parts. In some cases this is the way to go, particularly if you are into non-magnet racing on wood tracks or building a car for advanced levels of competition in which cost is not an issue. However, most slot car hobbyists do not need that level of performance for home racing and even many club competitions, especially where magnets are being used and cost containment is an objective.

I’ve pointed out in other articles that most hobbyists who race on plastic track can bring their stock ready-to-run cars to very satisfying performance levels and driving characteristics with nothing more than magnet and tire modifications. The same is true when creating your own custom-built cars.

A great way to put a complete running chassis under a resin or static kit body is to buy an RTR car and use it as a “donor” car. Any time you can do this it is significantly less expensive than buying all the parts individually, especially since you can sell the body and get back part of the car’s price.  There are even some manufacturers who sell complete running chassis without the body. Also, many of the factory replacement parts for cars from Scalextric, Monogram, Carrera, Pioneer, and others offer effective and inexpensive solutions to your special projects parts needs.  If you look at all the factory replacement parts made for RTR cars you will find an abundant source of effective, low-cost parts for building almost any car you can imagine.

Here are a few examples of improved and unique 1/32 scale cars built with factory replacement parts:

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This model is a “TransAm” Chevy Lumina converted from a 90s AMT NASCAR static model body (two of them, actually).  The complete running chassis is a box-stock Pioneer Mustang chassis with wheels and tires made for a Fly Porsche 934. The bodywork done on this car is quite extensive but putting a chassis under it was simplicity itself. The Pioneer chassis, used on all their 60s Mustangs and Camaros, is an exact match for the wheelbase of the body. Swapping the wheels and tires was the only change needed to give this body the chassis, wheels, and tires it needs.

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Here’s a heavily modified Monogram Cooper-Cobra. It uses the complete stock Sebring chassis with wheels and tires made for a Carrera Ferrari 512BB and an upgraded guide from Slot It. This car is literally the stock Monogram RTR with a lot of bodywork done to it to make it look like a Cooper heavily modified in the early days of Group 7 (USRRC-CanAm) racing to take an American V8 engine and wide wheels and tires with bodywork mods needed to cover the tires and give the car some aerodynamic add-ons to cope with all that Detroit horsepower. Bodywork like this is cheap, requiring only some sheet styrene and body putty (plus a good deal of work by the modeler). The rear tires are Maxxtrac silicones but you may be just fine with the stock tires. Try the car with the stock Monogram guide before you spend the price of the Slot It one.

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This CanAm McLaren M12 is a 70s Aurora vintage body on a Fly plastic sidewinder chassis with wheels and tires from a Monogram Greenwood Corvette. The original Aurora bodies turn up on eBay fairly often and resin clones are available from a couple of cottage industry manufacturers. The chassis under this particular car is a much chopped-up unit from a Fly Joest Porsche, but the Fly Ferrari 512S chassis and sidewinder rear pod, both available as spare parts, are a perfect fit for the body’s wheelbase. A used/semi-junk 512S makes an ideal donor car and you can even use the Ferrari wheels and tires if you prefer, though you might want to paint them aluminum with black or body-colored centers so their Ferrari origin is less obvious. This project also works with the more recent Flyslot inline 512S chassis. Both chassis are available as spare parts. The Greenwood wheels and tires are also available as spares, though they come in axle assemblies. The rear tires on this car are Maxxtrac silicones, but experience on our Scalextric track reveals that the stock Monogram tires give plenty of grip for magnet racing.

All these cars were inexpensive to build and required only basic modeler’s tools to create, yet are all good performers on the track.  You can do your own custom car projects by using donor car chassis and combining them in creative ways with the many stock replacement parts we sell in our on-line catalog.  Of course, we also carry high-performance parts from NSR, Slot It, and many others for those who need higher performance for all-out racing situations.  Your choices for giving every car you build exactly the look and performance level you want are nearly endless.  That’s a big part of what makes the slot car hobby so much fun for so many people with widely varying skills, specific areas of interest, and personal goals.

Copyright 2014 Robert M. Ward.  All rights reserved.

Paint Stripping With Alcohol

by Bob Ward

A while back I bought two used Fly Lola T70s on eBay.  The two bodies had multiple coats of paint on them that had to be at least a scale inch thick, so my first task in refurbishing them was to strip them back down to bare plastic, or as close to it as possible.  Paint stripping has been covered many times on various slot car web sites, but as long as I was going to do it anyway I decided to describe the process on the VLH site for the benefit of readers who may not have seen it elsewhere.

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I went to the local home improvement bigbox and bought a can of denatured alcohol, which can be found in the paint department.  Then I went across the parking lot to Wal Mart and looked through the housewares department for a Tupperware-type container just big enough to hold a slot car body.  The container has a tight-fitting lid, which keeps alcohol fumes contained.  It cost about $2.00.  I placed a body in the container, poured in enough alcohol to cover it, and snapped the lid in place.  After 24 hours the paint was ready to peel off the body.  It all came off quite easily except for parts of the initial primer coat, which didn’t seem to be as strongly affected by the alcohol.  Another overnight soaking seemed not to make much difference so I washed the body off and wet-sanded away the rest of the primer with 400-grit sandpaper.  I repeated the procedure with the other body and the result is as seen below, two bodies ready for repainting.

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The alcohol can be reused after filtering it through a piece of cloth placed in the funnel to remove any paint flakes when it is poured back into the can.  The alcohol is somewhat discolored by dissolved paint, but is still perfectly usable for more paint stripping.  It takes off the paint and does not harm either the body itself or the container.

Copyright 2014, Robert M. Ward.  All rights reserved.

Pickup Braid Basics

by Bob Ward

 Good electrical contact with the track is vital to the performance of any slot car.  In this article you will learn how to make sure your cars’ pickup braid makes and maintains the best possible contact.

A common beginner’s question is, “How and when do I change the braid on my new race set cars?” New slot car hobbyists also ask if the braid and lead wires are glued into the guide. Also, because the guide, braid, and lead wires are often sold as a unit in some manufacturers’ spare parts selections some newcomers initially assume they have to be replaced that way. We’re pleased to assure everyone that the braid can be replaced quickly and easily on all the cars we sell and that in virtually all cases it’s a toolless process.

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Ninco, Fly, Slot It, NSR, and many other makers of 1:32 scale plastic-chassis RTR cars use the guide design shown above. The braids are inserted in vertical slots and small ferrule-type connectors on the ends of the lead wires press-fit into adjacent holes.   When the ferrule is pressed into its hole it jams the braid against the inside of the guide, firmly holding both lead wire and braid in place in the guide.

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To replace the braid, first pull the guide down out of its socket so it hangs by the lead wires. Be careful not to pull the lead wires out.   Then, pull one lead wire and ferrule out of the top of the guide and pull the braid downward through the bottom of the guide. Slide the new braid downward through the top of the guide until about 1/16” of it remains above the top of the guide. Bend that 1/16”of braid back over the top of the guide and press the lead wire, with its ferrule connector, back into the top of the guide. Bend the braid back along the bottom of the guide and adjust it for proper contact with the track. It should be bent down far enough to make solid, positive contact but should not exert enough pressure to lift the front end of the car.  Repeat the procedure on the other side, snap the guide post back into its socket, and you’re back to racing. You should have only one lead wire disconnected at any time. This assures that you will always get each lead wire plugged into the same side of the guide and your car will always run in the same direction.

Older Scalextric cars and SCX cars use a “wireless” electrical system, in which no wires go into the guide. Instead, each of the two extra-long braids wraps around the top of the guide and metal shoes on the bottom of the chassis make contact with them.   Both Scalextric and SCX sell packages of guides already made up with braid on them. To change braid, just snap the guide down out of its socket in the chassis and snap a new one, with new braid, back in. This is about as user-friendly as you can get.  The Scalextric and SCX braid setup are shown below.

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You can modify your Scalextric cars’ braid to the SCX configuration for improved electrical contact.  Get a 1m length of copper braid. VLH carries several brands to choose from. Cut off two 1.25” (32mm) lengths of braid  Remove the steel braid from your Scalextric guide by sliding it out sideways. Then, just wrap the new braid over the guide and bend it as shown below and you have better braid with both ends touching the track for increased contact area and better conductivity.

More recent Scalextric cars use the “braid plate” guide design, in which the main portion of the guide remains in place on the car and a plastic disc holding both braids snaps into place. The procedure for changing braid on these cars is shown below. You just slide the braid plate forward, lift up the front edge of it, slide it back over the guide blade, and it’s off. Installing the new braid plate, with new braid on it, simply reverses the procedure.

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Over time the guide can wear where the braid plate slides in and out until the plate is no longer a tight fit in the guide. Then the braid plate will come loose and fall out in a crash. At that point the guide needs to be replaced.

Pioneer Models equips its cars with its own unique guide design. The guide has an extra-long post. This allows it to be pulled down below the chassis for braid changes without detaching it from the car.

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The braid comes with a brass clip on the end that presses into the front of the guide in the same manner as the braid used in the venerable Jet Guide that has been universal in 1/24 scale commercial track racing for decades.

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Changing braid is simply a matter of pulling the old braid out of the front of the guide and pressing the new ones in. Then push the guide back up into the running position and you’re ready to race. You never need to remove the lead wires from the guide while changing braid.

In addition to keeping fresh braid on your cars you also need to be sure the braid is kept clean and adjusted properly for positive contact with the track and proper alignment with the track’s contact strips. Slot car braid is made from flat braided wire, either steel or copper, which has a certain amount of “spring” to it. The spring action allows the braid to maintain positive contact with the metal strips in the track as the car moves. The object in adjusting the braid is to bend the braid downward from the bottom of the guide just enough to give it positive contact without putting so much tension on it that it tends to lever the front of the car upward, lifting the guide partially out of the slot and degrading the car’s handling.

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In the drawing above, #1 shows the correct way to bend the braid, down just far enough to make good contact. #2 shows the braid bend down too far, and #3 shows the braid flat against the bottom of the guide, where it may not contact the track at all. To get just the right braid adjustment on any individual car may require a little trial and error, but with experience you will learn to get just the right tension on the braid quickly and easily every time. The same principle applies to braid on all types and makes of slot car whether they have single or double braids. With use, braid eventually loses its spring and will no longer maintain positive contact. When this happens you will need to replace it. braidadjust1a.jpg

In addition to being adjusted up and down for correct tension the braid also must have the proper alignment. #1 above shows proper side-to-side alignment of the braid. The braid is directly over the track strips and makes contact with their full width. #2 shows the braid splayed outward and not making good contact with the track strips.  It’s also important that the braid not be allowed to develop a twist that leaves it with only the inner or outer edge contacting the track strips. #3 shows the braid making even contact with the track strips across its entire width for maximum power and performance as well as consistent contact. #4 shows the braid twisted so that either the inner or outer edge is making contact with the track.

Along with proper adjustment you will need to keep the braid clean. As your cars run the braid accumulates dust, dirt, and other foreign substances from the track. To clean it you can use WD 40 or any of the common braid cleaning products. Be sure to check your braid for proper adjustment after each cleaning.

 If you have questions or comments about this article we invite you to e-mail e-mail them to bob@victorylaphobbies.com or call at (insert phone number here). We’ll be glad to give you all the information and advice you need.

 

Copyright ©2014 Robert M. Ward. All rights reserved.

There’s Oil In Them Thar Bushings – Lubricating Your Slot Cars

by Bob Ward

Your slot cars need lubrication in the right places to run properly.  Here are the basic facts you need to know.

Slot cars are like any other mechanical device; they need lubrication to run smoothly and quietly, avoid excessive wear, and delver maximum performance. If you ask ten slot car hobbyists what the best oil for slot cars is you will get at least eleven answers.   The truth is, however, that unless you are going to race at the highest levels of competition almost any lightweight plastic-compatible oil will work. So, before you buy the latest hot trick slot car lube (even from us here at VLH) look around the house to see if you already have something that will serve the purpose. Most people do, usually from another hobby like model trains or just for household use. Then, if you still need to buy oil check our selection under the Tools and Supplies category.

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The photo above of a typical slot car chassis shows the places where your slot cars need to be oiled. These include the rear axle bushings, the front axle bushings (or, in many cases, just holes in the chassis for the front axle), and the motor shaft bushings. If your car has the motor up front and a drive shaft going back to the rear axle there will be a bushing just forward of the pinion gear that also needs lubrication. The plastic gears that come on most ready-to-run (RTR) slot cars do not really need lube even though some of the manufacturers apply a lightweight grease to them at the factory.

You don’t need more than a tiny drop of oil at any of the lubrication points. Excess oil will just gunk up the inside of the car or drip on the track. Too much oil also causes dirt, fibers, hair, and other tiny environmental debris to stick to moving parts. This is especially important when oiling the motor shaft bushings. If too much oil gets inside the motor it can reduce performance or even cause the motor to stop running. The two key words to remember about oiling your slot cars are sparingly and infrequently. Hobbyists are much more likely to over-oil their cars than to under-oil them.

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Over time, some oil and dirt will accumulate inside your cars and it’s a good idea to clean it off regularly. I’ve found that the best tool for doing this is a small natural bristle trim paint brush. You can find them at any home improvement store for less than $1 each. You just brush the inside of the body and chassis and the bristles soak up fluids while sweeping up solids. They get into all the nooks and crannies better than any rag or cotton swab. In a few moments you can have your car’s insides looking as clean as new. When your brush has soaked up too much oil just discard it and use a new one.

Volts, Amps, and Ohms

A brief introduction to basic electrical concepts

 By Bob Ward

You may be one of the many new hobbyists getting involved in slot car racing who haven’t yet acquired an understanding of the basic electrical principles that determine how a slot car runs and responds to control inputs. So… here’s a little primer that should help with common questions.

The race set’s power system plugs into a wall outlet and takes in 110 to 120 volt alternating current (AC). It delivers to the contact rails on the track 12 to 18 volts (depending on the system) direct current (DC) on which the cars’ motors run. In most track power systems this conversion takes place entirely in the wall-mount power pack. On Scalextric’s, however, the “wallwart” contains only the transformer, which lowers the voltage, while the rectifier, which turns AC to DC, is in the terminal track section, most commonly called a connection straight or power base track.

Electric current is measured in both voltage and amperage. Voltage is sometimes compared to the pressure in a water main, while amperage is analogous to the volume of water passing through the pipe.

The more voltage you feed to a motor the faster its armature will turn until the motor overheats or the centrifugal force of the armature’s rotation exceeds its structural capabilities and some part of it flies off. Either way critical parts of the motor self-destruct. When that happens with the motors commonly used in home set slot cars, it’s time for a whole new motor.   Running a 12-volt motor at 14 or even 16 volts probably won’t shorten its life too much. Bumping the power to 24 volts will let the smoke out in rapid order.

Amperage affects performance differently. A motor will only draw as much amperage as it can use. If the power supply is not delivering enough amperage supplying more will increase motor performance but only until the motor’s needs are satisfied. After that, all the amperage in Grand Coulee Dam won’t make the motor run faster. It won’t harm it, either, but it will increase the probability of catastrophic damage to track and controller wiring in the event of a short circuit.

To drive a slot car you have to vary its speed using a hand-held controller. There are two kinds of controllers in common use, resistance controllers and solid-state electronic controllers. Race sets come with resistance controllers because they are less expensive to produce than electronic ones and keeping down the overall cost of the race set is essential

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A resistance controller varies the cars speed by introducing resistance, measured in ohms, into the circuit. The controller acts like a valve in a water main, preventing a greater or lesser portion of the available current from reaching the car’s motor and thereby changing the car’s speed.   When the controller trigger is in the off position the circuit is broken completely and no current is flowing. When the trigger is pulled back just a little, the resistor holds back most of the current, converting it to heat, and the car moves slowly. As the trigger is pulled back, more of the current passes through and the car goes faster.     Finally, the wiper button on the trigger makes contact with the full power band on the resistor and all the power reaches the car’s motor, just as if it were hard-wired to the power supply.

The biggest single factor determining whether the driver’s experience will be fun or frustration is his ability to control the car effectively. To do that, the controller’s resistance must match the requirements of the car. If the resistance is too low the car will take off at high speed and reach full throttle before the controller trigger is pulled all the way back. If the resistance is too high the driver may have to pull the trigger as much as halfway back before the car even begins to move. In either case he will have only a portion of the trigger’s travel over which to vary the car’s speed and it will be much harder for him to drive the car competitively.   When controller and car are properly matched the car begins to move slowly as soon as the trigger is pulled even slightly. It continues to accelerate until it reaches top speed just as the wiper button reaches the full power band.

Most 1:32 scale race sets available today come with controllers that have too much resistance for the cars, typically around 60 to 70 ohms. Non-magnet cars do fine with such controllers, but virtually all race set cars now come with traction magnets and the magnet-equipped cars are happier with 45-ohm controllers. Modified cars with strong magnets and/or more powerful motors would be better off with 30-ohm controllers and more power pack amperage as well. Parma controllers, available pre-wired with plugs for the various manufacturers’ terminal tracks, are a popular and reasonably economical upgrade for many race set owners. In choosing resistance controllers there’s a big subjective factor at work. One driver may be most comfortable driving a particular car with a 60-ohm controller while another may prefer 40 ohms with the same car.   A controller can be adapted for different types of cars by changing the resistor to one of a different ohm rating.

A solid state electronic controller bypasses these issues because it uses electronic circuitry instead of a resistor to control the car’s speed. This means that one controller of this type can properly control cars with a much wider range of driving characteristics and also accommodate a wider range of driver preferences. This allows one set of electronic controllers on your track to work well with an assortment of cars that might require two or three sets of resistance controllers. Electronic controllers are also available with plugs for all the common track systems. Higher-end electronic controllers also offer adjustments such as variable braking and variable sensitivity that further increase their versatility.

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Most race set power packs don’t really deliver enough amperage to completely supply the needs of two cars. With the set’s own cars and others with similar current requirements this isn’t too much of a problem, but when the racer starts buying strong-magnet cars or puts powerful aftermarket magnets or motors on his race set cars, he finds his cars starved for amperage. Neither car achieves full performance when both are running and when one stops or deslots the other gets a blast of power that often sends it off the track.   A power system upgrade that feeds each lane separately with its own power supply will meet the requirements of virtually any kind of car a hobbyist is likely to run on his plastic home track and ensures that nothing one car does can affect the amount of current received by the others. This can sometimes be done using the manufacturers’ standard power packs.   Scalextric, unfortunately, has stopped making its C8217 and C8241 power bases that offer the option of powering the lanes separately but they can still be found on the Internet if you look for them.

The other alternative for providing adequate amperage is to buy an aftermarket power supply and adapt it for use on your track by grafting the appropriate plug onto the power supply-to-track wiring.

Power issues can be some of the most confusing ones confronting newcomers to the hobby, and determining the best combination of components for your specific needs may require some expert help, at least until you acquire some experience. We’ll be glad to help with advice and information. You can call us toll-free at (insert phone # here) or e-mail us at (insert address here).

Copyright © 2014 Robert M. Ward. All rights reserved.

Working With Slot Car Drive Shafts

By Bob Ward

 

Drive shafts are a feature of many slot cars in use today.  In this article you will learn what you need to know about them.

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The front-motor in-line motor/chassis arrangement has become fairly common since the slot car racing renaissance beginning in the 1990s but it really got started back in the 1960s. The purpose was the same then as now – to allow a deeper and more detailed interior than just a flat tray with a driver figure. Strombecker, a prominent manufacturer at the time, had front-motor cars as early as 1960, but these cars used a piece of rubber tubing to couple the motor to the drive shaft. Later versions used a very long one-piece motor shaft that ran all the way to the rear axle. Before long Strombecker moved to rear-motor inline designs and front-motor cars disappeared for decades. However, with the introduction of strong neodymium traction magnets in the 1990s they made a comeback and have been quite successful on cars for plastic sectional track with steel contact strips. Fly has used the arrangement in all its models of front-engine cars. Scalextric uses it in models of 2-seat front-engine sports cars to make possible the fitting of a full interior. Revell-Monogram and MRRC have also made extensive use of it. The chassis of two front-motor cars, a Fly Ferrari GTO and a Scalextric Dodge Viper, are shown above.

The front-motor arrangement seems at first to be an unlikely drive train configuration for a slot car, since it places the motor’s weight at the opposite end of the car from where it’s needed for maximum cornering grip.   That flies in the face of proper principles of weight distribution for optimum handling. But with a stout magnet at the rear providing downforce the arrangement becomes viable. If you want to race non-magnet, however, you will do better to run a rear-motor car or convert your front-motor car to a rear-motor configuration. That kind of conversion, by the way, is not hard to do on a plastic chassis. All it really takes is a few basic hobby tools, a piece of sheet styrene or ABS, and a bottle of CA glue.

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All the Fly, MRRC, and Scalextric front-motor cars use very much the same endbell-drive motor and drive shaft assembly. The difference from one car to another is only in having a longer or shorter drive shaft length and sometimes different connectors on the ends of the lead wires. The motor, shaft bushing, pinion gear, and spring coupler are interchangeable on all of them, as are the various mounting points in the chassis. (Drawing 1) Thus, if you have any Fly, MRRC, or Scalextric motor and drive shaft assembly you can use it in any of these manufacturers’ cars or in a scratchbuilt or kitbashed car using one of their front-motor chassis simply by lengthening or cutting the shaft as necessary. Since the shaft diameter on every motor currently being used in 1:32 scale front-motor home racing cars is .078” (2mm) you can easily and inexpensively make a longer shaft by getting a piece of .078” steel wire from the K&S metal rack at your local hobby shop and cutting a length to fit your car. In a Fly, MRRC, or Scalextric front-motor car you can use any endbell-drive Mabuchi S can (FC130) or other motors with the same external configuration. The motor will fit the chassis and the drive shaft and spring coupler will mate up with the motor’s shaft. In some cases, however, you may need to trim the motor shaft, either on the end that mates with the drive shaft or on the opposite end to clear parts of the chassis. This can be done easily with a Dremel Moto-tool equipped with a carbide cutoff wheel. Be sure not to let the motor shaft get too hot when cutting it, as this can damage the bushings.

Revell-Monogram uses the same arrangement but with a can-drive FC130 motor. R-M’s shaft bushing and pinion gear are compatible with Scalextric, Fly, and MRRC. Again, shaft length differences apply.

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Removing the drive shaft from the motor and reconnecting it is not difficult, but many people have trouble getting the spring off without stretching it. The key is always to push the spring off the motor shaft or the drive shaft, as shown in Drawing 2, rather than pulling it. Place the jaws of your needle-nose pliers on the motor shaft between the endbell bushing and the spring coupler. Slide them along the shaft, pushing the spring coupler as you go. The coupler will normally come right off with only light pressure. Use the same technique to remove the coupler from the drive shaft as shown in drawing 3.

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When it’s time to put the coupler spring back in place it just pushes onto the shaft. Fly and Scalextric motors have a splined shaft end to better grip the spring coupler. If you are installing a hopup motor from another manufacturer it may not have the splined shaft end and may not fit the coupler tightly.   In that case, use a drop of medium CA glue in the spring coupler to hold it tightly to the shaft (Drawing 4). Don’t use the thin CA, as it can easily run into the shaft bushing and lock up the motor. Before using any kind of CA on a motor shaft or a drive shaft be sure to put a drop of oil in the motor and drive shaft bushings.     Be careful not to get any oil where the CA glue will go.

You can use a gear puller to remove the pinion gear from a drive shaft assembly without removing the shaft from the motor, but you have to remove the shaft before you can press a pinion back on. Once the spring coupler is removed you can use a pinion press on the drive shaft exactly as if it had a motor around it. If you do a lot of gear changes you will save time by making up several shafts, each with a pinion gear with a different number of teeth. Whenever you put the shaft assembly back together don’t forget to put the shaft bushing back on before reattaching the drive shaft to the motor shaft.

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One of the biggest problems with some front-motor cars is the drive shaft bushing’s tendency to pop out of its mounting in a crash or even a hard spin. When this happens the pinion gear starts chewing teeth off the crown gear and after that the car never has a smooth, quiet gear mesh. We have heard from customers who have glued or wired the bushing in place, but we don’t recommend either of those measures because they make the bushing difficult to remove when you need to. There’s a better way, as shown above in Drawing 5.   All you have to do is cut a piece of styrene strip or basswood about 1/8” by ¼” and glue the end of it to the bottom of the car’s body, interior tray or tub so the end of it presses down on the shaft bushing when the body is in place on the chassis. It will take a bit of cutting and trying to get the exact location and length needed, but once you get it right it will permanently end all problems with the shaft bushing coming loose without making it hard to remove.   Some front-motor cars come with an arrangement like this already in place.

With this information you should now be equipped to repair, replace, or modify the drive shaft assemblies on any of your front-motor cars with the fewest possible problems. Good racing!

If you have questions or comments about this article we invite you to e-mail e-mail them to bob@victorylaphobbies.com or call at (insert phone number here). We’ll be glad to give you all the information and advice you need.

Copyright ©2014 Robert M. Ward. All rights reserved.