Pinewood Derby Car Showcase – February 28, 2012

Some cars that appeal to the feminine side.

Purple Pixie – Gary Olesky

Little 4 year old Ali and adopted grandpa for the day, Gary Olesky, took on her brother Sebastian and all the other boys at a Cubscout pinewood derby Race. The boys were not happy losing to the purple and pink pixie car, which turned in the fastest time of the day.

The Shoe – Jeremy Isaac

My daughter ran the shoe, which took first in both Speed and Novelty in the Awana Cubbies division. The speed competition wasn’t very stiff this year – the car was reasonably fast, but shouldn’t have won in my opinion.

Blue Flower – James White

My granddaughter (Olivia) and I built this car for her to race against her brother. Olivia calls her car “Blue Flower”.

From Pinewood Derby Times Volume 11, Issue 11

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(C)2011, Maximum Velocity, Inc. All rights reserved.

Shop Talk – Bench Top Power Sanders for Pinewood Derby Car Building

By Randy Davis

If you build more than one pinewood derby car per year, then you will already know that shaping a car without some type of power sander is a real chore. Just eliminating the teeth marks left by the saw is a chore,  much less trying to create nice curves and contours.

I have used many different power sanders, so in this shop talk I’ll share the ins and outs of the various products that are available  (and affordable) for the home shop.

A Word of Caution
With any power tool, precautions must be taken to avoid personal injury. Always wear eye protection, tie up long hair, remove hanging jewelry and tuck in shirts. Always read and follow the manufacturer’s safety warnings. Finally, power sanders produce a lot of dust. So, where possible use dust collection equipment, and always were a dust mask.


The first power sander I used was a belt sander, turned upside down and clamped to a work bench. Let me tell you, this was a big step forward from hand sanding, as you can really take off a lot of wood, and can readily make contours.

Figure 1 – Belt Sander

But please note that I do not endorse this method of using a belt sander, as it is not intended to be used this way. This method of sanding introduces several problems. First, the sander wants to take the car body right out of your hand and throw it against the wall (or automobile, or whatever is in the way). You really have to hang on to the car body. The second issue is that if you do not apply even pressure on the block, you can easily end up with a lopsided block. Finally, especially with thin cars, the tips of your fingers are fair game for abrasion, so a lot of care must be taken.

Home Depot List Price: $50 and up

A big step up from a belt sander is a Belt/Disc Sander. These come in several varieties, one of which is the Ryobi model shown in Figure 2.

Figure 2 – Ryobi Benchtop Belt Sander
(Source: Ryobi website)

The Belt/Disc Sander is a bench top tool (meaning it is screwed down to a work bench), so clamps are not required. The belt sander part is equipped with a stop, so that the car body is not easily taken out of your hand. The disc sander part is nice for sanding the back end of the car and for making round corners. Since the disc is square to the supporting table, you can ensure that a right angle is formed when using it.

Of course, like the belt sander, the belt/disc sander can still remove finger tips, and when using the belt, poor technique will result in uneven cars.

Home Depot List Price: $119

A specialty power sander that can be used is the narrow belt sander. It is much less common as it is not as useful as the belt/disc sander (however, there is a combination narrow belt/disc sander available).

Figure 3 – Central Machinery Narrow Belt Sander
(Source: Harbor Freight web site)

The narrow belt allows you to sand straight edges that are inset into the car body, such as on our Arrow design (Figure 4). However the edge of the belt can cut into the wood, so you need to continually move the car body back and forth across the belt, and apply minimal pressure..

Harbor Freight List Price: $50

Figure 4 – Standard Wheelbase Arrow


Another type of sander that is handy for building pinewood derby cars is the spindle sander. The spindle sander has sanding drums of various diameters that are used to create concave curves. For example, a spindle sander would be used to create the side on our Detonator design (Figure 6).

Figure 5 – Delta Spindle Sander
(Source: Delta Tools web site)

Figure 6 – Standard Wheelbase Detonator

Spindle sanders oscillate, that is, the sanding drum moves up and down to maximize the use of the drum and to increase the sanding action. They also have some type of dust collection, so less dust piles up on the support surface and hovers in the air.

Spindle sanders are special purpose (like the narrow belt sander), so unless you make cars with convex curves, it will tend to just collect dust. But when you have a need for it, the spindle sander is a godsend.

Sears List Price – $300
(A less expensive model is available at Harbor Freight)

I have a confession to make; I don’t use any of the products listed above anymore. Several years ago I ran across the Ridgid Oscillating Edge/Belt Sander (Figure 7), and it is the only sander I now use.
Figure 7 – Ridgid Oscillating Edge/Belt Sander
(Source: Ridgid website)

The Ridgid sander is a home shop version of a floor mounted oscillating belt sander used at most cabinet shops. Back in high school, I worked at a cabinet shop, and used a commercial oscillating belt sander every day. So when I found the Ridgid sander, I knew it was a must for the shop.

The sanding belt (which is a standard size used on regular belt sanders) oscillates up and down, maximizing the use of the belt and increasing the sanding action. It is square to the work surface, so you can ensure that the sides of your car are square to each other. A stop is included to keep the car body from flying away. The stop can be easily removed so that the large diameter drum (left side in the photo) can be used for rounding inner curves.

But that is not all. If the drum is too large, the Ridgid sander easily converts to a spindle sander (Figure 8). It comes with five different drums, and the parts to make the drums fit properly.

Figure 8 – Conversion to a Spindle Sander
(Source: Ridgid website)

As with any belt sander, care must be taken to avoid abrading a finger. Also, dust collection is a necessity. This sander produces lots of dust, and if the dust is allowed to collect in the area under the oscillating belt, it will eventually clog up the machine. The sander is equipped with a dust collection port in the back, which can be attached to a shop vacuum or to dust collection equipment. Make sure to do so.

Home Depot List Price – $200

Although all of these sanders have their purpose, I believe the Ridgid sander is the best choice for most pinewood derby projects. It combines the best features of a belt/disc sander with the benefits of a spindle sander.

From Pinewood Derby Times Volume 11, Issue 11

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(C)2011, Maximum Velocity, Inc. All rights reserved.

Open Competition Races

Many organizations give parents and siblings an opportunity to race by sponsoring an open competition race. Typically the rules for these races are somewhat relaxed, allowing more innovation and creativity in car design.

In today’s article I would like to first share some typical ways to ‘open-up’ the rules for this type of race. Then I would like to explore a more radical way to add excitement to your derby event.


Here are some common ways to allow more flexibility in open competitions:

1. Wheelbase – If the organization event mandates the use of a standard wheelbase (distance between the front and back axles) then allow the wheelbase to be modified as desired, as long as the overall length specification is maintained.

2. Alternate axles – Instead of requiring the use of the organization standard axles, allow the use of after-market ‘speed axles’.(1)

3. Wheel shape – Typically, standard rules allow minimal wheel modification (e.g., only a light sanding). Try removing this restriction, thus allowing wheels to be lathed flat, narrowed, equipped with a grooved tread surface, and/or overall weight reduction.

4. Length – Try changing the maximum length from the typical seven inches to twelve inches (or one inch less than the distance from the starting pin to the back edge of the track).

5. Weight – Consider changing the maximum weight to one or more pounds (with standard wheels and axles, I don’t recommend exceeding 1 pound).


Wouldn’t it be fun to add a whole new dimension to your open competition? I’m thinking of power!

Okay, I know what you’re thinking. Someone will strap a rocket engine on the car, and damage the track, a person, or the building! But of course, restrictions would be necessary to minimize any risk. So, I suggest the following rules.


— Dimensions —
(Adjust to fit your track, and leave an open lane between cars)

– 11″ max length
– 5″ max width
– No limit on height (remove the electronic finish line)
– 3″ max inside wheel base
– 3/8″ minimum track clearance
– 32 ozs. max weight

— Power Sources —
In addition to gravity power, other power sources may be used as long as they do not pose a risk to the spectators or to the track.

1. Allowed power sources include, but are not limited to electrical, mechanical, and pneumatic.

2. Power sources which use combustion of any type are explicitly disallowed. This includes combustion engines, rocket engines, and explosives.

— Wheels, Axles and Body —
A pinewood derby kit may be used, but it is not required. Any material can be used for the car as long as the finished product meets the specifications. However, the wheels must be made of a material that  will not damage the track. Metal, ceramic, glass, or other hard  substances may not be used for wheels. Allowable materials include plastic, rubber, and wood.

— Race Procedure —
The owner of each car will stage the car on the starting line, and pick the car up at the end of the run. Cars may be adjusted between races as long as the adjustment does not delay the race. However, cars may not be lubricated during the race.


I have heard of all sorts of ideas for adding power to pinewood derby cars Listed below are a few that have merit.

— Powered Rear Axle —
– Spring wind-up mechanism
– Rubber-band powered
– Mouse-trap powered
– Electric motor powered (R/C type)
– Weight powered (suspended weight drops and turns rear axle)

All of these ideas can be made to work. But two problems must be worked out:

1. How to apply power when the starting pin drops, or
2. If power is applied before the pin drops, how to apply the maximum torque without the wheels spinning-out.

— Non-powered Rear Axle —
The design ideas below eliminate problem number 2 above, but problem number 1 must still be resolved.

– Compressed CO2 or Air (acts like a ‘jet’ engine)
– Propeller powered (push or pull)


I have had some experience with propeller power, so I would like to share the design of a car that I built a few years ago. I have also included photos of a few cars submitted by readers.

— My Propeller Car —
Please don’t laugh too hard. If I had the opportunity to do this again, I would shorten the car and reduce some of the infrastructure. Nevertheless, this car smoked the competition, and easily beats any standard pinewood derby car.

Front View

Rear View – v3_i5_propcar2.jpg

Here is a parts list and some notes on implementation.

– Motor: 12 VDC motor, RF-370CA by Mabuchi Motors:

This is a VCR motor, but other motors would work as well. I drove the motor at 18V for more power. This would eventually burn out the motor, but the on-time is so short that the motor doesn’t get a chance to overheat.

– Motor Mounting: The two screw holes on the font of the motor are for
mounting. The required ISO screws can be purchased at a hardware store. I used a piece of thin stainless steel (hardware store item), drilled holes for the mounting screws, shaft, and assembly bolts (see front view picture).

– Propeller: I used a plastic prop intended for rubber band powered airplanes. The hobby store I visited sold them in packs of three. The prop is about 4″ long and I had to trim the tips a bit for clearance. The shaft hole was too small, so I drilled it out to fit snugly on the motor shaft. I then epoxied it in place. I believe this type of propeller works better than an R/C airplane propeller. They are too heavy and the blade angle is smaller, providing less thrust.

– Infrastructure: I had access to an old erector set, but you can use any light metal strapping. It does need to be securely mounted as some torque is generated. Make sure there is clearance for the propeller. I had to remove some metal from the erector material. If you look carefully at the front view, you can see where it is removed.

– Motor Shroud: Quaker Oats oatmeal container. I put this on for two reasons: (1) To keep hands from touching the blades (it hurts, but doesn’t cut if you touch the spinning blades), and (2) To keep the blade from breaking if the car rolled over. The propeller is epoxied to the shaft, so if the blade comes off, the race if over.

– Motor Alignment: The motor does need to be pointing as straight forward as possible. Add/remove small washers where the stainless steel strap fastens to the infrastructure to adjust alignment.

– Starting Pin Switch: I used a contact switch (similar to part #275-016 at It is normally on. When the car rests against the starting pin, the weight of the car closes the switch turning the motor off. Thus, when the pin drops, away it goes.

– Kill Switch: If you look carefully at the front view you will see a small toggle switch. That is used to turn the motor off when not in use. Just make sure to turn it on at the starting gate!

– Batteries and Holders: Two standard 9V batteries. The battery holders and clips are Radio Shack items.

– Wiring: Light gage electronics wire. Positive side of the battery goes to the Kill Switch, then to the Starting Pin Switch, then to the motor. The negative wire goes to the motor. Batteries are wired in series.

– Wood: Pine, 1-3/4″ wide. The car is 10″ long, but it could be shortened to 8″.

– Wheels/axles: Standard BSA issue. Axle holes are drilled with a drill press. All four wheels touch the ground.

— Reader Propeller Cars —
Here are a few propeller cars sent to me by readers.

Keith Gosselin

Like my car, this one has a starting pin contact switch and a kill switch. Hanging the propeller (tri-blade in this case) off the back of the car, permits the use of a longer propeller.

Mark Pugsley

A similar design using a rubber band airplane propeller (and liberal use of rubber bands in the infrastructure).


A dual prop model that uses an R/C type battery and control. (This photo was sent to me by another participant in the race. If this is your car, please let me know so that I can give you credit).


Maybe this all seems a bit ridiculous to you. But I guarantee that if you have a group with a lot of handy parents, an open competition race with power assist is a blast and a certain crowd-pleaser!

(1) See Speed Axles for aftermarket axles.

From Pinewood Derby Times Volume 3, Issue 5

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(C)2011, Maximum Velocity, Inc. All rights reserved.

Woodworking Tip

Here is a tip that I have used many times to repair broken appendages, saw mis-cuts, and any other case where too much material has been removed from the car. The answer: Bondo auto body filler (which works better than wood putty). It can be mixed to harden in 15 minutes or less to a point where it can be shaped with a knife or rasp or file or sanded. It is usually softer than the wood and can be sanded away without taking much from around it.

My daughter designed a hammerhead shark for her Awana grand prix car two years ago and I broke off about 1/2 inch of the tail while doing something (I don’t remember what, but I had to fix it). I tried to glue the piece back on but it kept falling off. I ‘globbed’ some Bondo on and shaped it with a knife and sandpaper and it lasted through all of the races and is still in place (she even took 1st Place for design that year). You can also use Bondo spot putty to fill in end grain or deep sandpaper scratches or nicks or dents or any small problems. It dries in about 5 minutes, and then can be sanded. I always paint the “finished” cars with primer to be able to see any of these small problems and then fill them with spot putty.

Pete Walker

From Pinewood Derby Times Volume 3, Issue 3

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Buying a Track? – Important Points to Consider

By Steve Monk

Selecting and buying a pinewood derby track for your group or organization is a great responsibility and often a considerable investment. So, careful consideration of the various features and options is certainly appropriate.

To help you in your decision, here are some things to consider when shopping for your ideal pinewood derby track.

Probably the number one complaint heard at many races is “One lane’s faster than the other!”, and often it is.

— Track Joints —
A major source of lane unfairness is the smoothness of the track joints, a common problem on wood tracks where wear-and-tear and warping  affects the joints. This was the most frustrating problem we had with our local pack’s tracks. We had one track which was several years old and showing considerable wear. Many hours were spent each year to shim and even out the lanes. We even tried wood putty in the joints, and gluing and nailing down the plywood lamination to make the joints smooth so they wouldn’t throw cars off of the track. No matter how much care was taken we still had one lane faster than the other. Our final races were so close that when it came down to the last couple of cars, we couldn’t determine a winner because whichever car was in the “fast” lane always won. One of the leaders in our group volunteered to build a new track for the next year’s race. Even though it was brand new, we still had a fast lane.

— Track Finish —
Wood warps, and unless you have a humidity controlled environment, you will need to seal a wood track with a varnish or urethane finish of some sort. Unfortunately, it’s nearly impossible to apply a paint or varnish to a wood track and have it come out equally smooth and even the entire length.

Non-wood tracks are less susceptible to both of these issues. Neither aluminum nor plastic tracks require a sealer. Moisture may cause discoloration, but it doesn’t affect the performance of the track. Aluminum tracks are virtually unaffected by temperature or sunlight, while plastic tracks can be sensitive to both.

The starting gate is an important component to consider when buying your track. To ensure that the start is consistent for each race, the starting gate should have the starting pins held in the up position by a latch. The pins should then swing down quickly under power when released. Ideally, the power source (spring, rubber band, etc.) should be adjustable by the user to drop the gate as quickly as desired. Some start gates have the starting pins held in the up position with a spring, and operated by pushing down on a lever by hand. Inconsistency by the starting gate operator can cause inconsistent starts. Also, if the lever slips out of the operator’s hand as the cars are passing over the starting pins, the pins can pop back up, launching the cars off the track.

What do you do if your group doubles in the next year? Can you expand your track or do you have to replace it? Some tracks, especially wood ones, are built to a specific length and width, and are hard to expand. Aluminum tracks are extruded one lane at a time and can be easily expanded in length or width as your organization grows and your budget allows.

Most home built wood tracks follow the suggested track designs found in Cub Scout manuals or on the internet. These designs often follow the standard 3-1/2 inch lane width and the 1/4 X 1-5/8 inch center guide. The center-guide design probably represents 98 percent of all tracks in existence.

Edge guide tracks control the direction of the car with raised edges of the track. The advantage of an edge guide track is that a car with the wheels set too high on the body, or too far in from the ends has less of a chance of dragging on the bottom while going through the curve. Weights attached to the bottom of a car can cause dragging on a center-guided track.(1)

A disadvantage of edge-guided tracks is that the many pinewood derby wheels (BSA, PineCar, Awana, etc.) are designed for center-guided tracks.(2) The inside edge of these wheels are smooth (at least after some work), while the outside has serrations, raised lettering, spokes, etc. These features can hamper performance on edge-guided tracks.

Another disadvantage of edge-guided tracks is that they are different than most other tracks. Since edge-guided tracks represent only a small percentage of tracks in use today, using one at a local race could affect the cars that advance to a district race. A car that performs really well on an edge-guided track may not perform as well on a center-guided track.

Safely stopping your Pinewood Derby car is important. You don’t want to win a race and then have your car zoom across the floor, crash into a table leg, and knock off a wheel, thus eliminating the car from the rest of the race. A good stopping system will gently slow the cars to a safe stop in a short distance without damage. Many groups use pillows or coats or whatever is handy. I have even seen plans for a top dragging carpet stop which suspends strips of carpet over the end of each lane. This works pretty well except it also rips off some of the fine detailing some racers add to their cars, such as radio antennas, mirrors, etc. A similar foam “garage” design could have the same problems.

The best stop systems stop the car with a raised center lane. The cars then skid to a stop on their ‘bellies’. These stop systems either have the rolling surface drop away to a raised center strip, or they use a ramp to raise the cars off the track.

Most wood tracks are built from standard dimension plywood which is 8 feet long. Tracks made from other materials are not constrained by standard lengths and can be made economically in any length sections. With 7 foot sections, the track can be transported in an SUV or minivan. However, with 8 foot sections, a truck or large van is generally required.(3)

Weight is also a factor to consider. Wood tracks can be quite heavy, thus increasing the risk of damage due to bumping or dropping the track. Other track materials (aluminum and plastic) are much lighter, greatly easing transport and reducing the risk of damage.

The support structure of the track should be sturdy and rigid to give good support and prevent swaying if bumped. Flimsy support stands could cause cars to jump off of the track if the track is bumped during a race.

Pay close attention to the amount of work required to set up the track on race day. Most tracks need some sort of pre-assembly the first time they are set up. However, on race day the track should be able to be set up with a minimum of fuss and time. This is especially important as race officials change from year to year. If the track requires a lot of time and knowledge to set up, each new team will have their hands full, at a time when they don’t need the stress!

The initial set-up is also a factor. Tracks with pre-drilled or pre-punched components, and sliding bolt slots or other features will not only speed assembly the first time, but will also ensure continued ease of use long into the future.(4)

Ultimately, the major consideration when purchasing a track is whether the track will provide many years of quality, trouble-free racing. So time spent considering the various options is certainly warranted. I hope that these track considerations will greatly help you in your purchase decision.

Steve Monk is the President of SRM Enterprises, Inc., the manufacturer and distributor of BestTrack Aluminum Pinewood Derby Tracks. SRM Enterprises is a small family run business building quality products and serving satisfied customers since 1984. Here is a personal note from Steve:

“Frustration with our local Cub Scout Pack’s track is what led me to start building the BestTrack aluminum pinewood derby track. As a scout leader I took it personally when a parent would complain that one lane was faster than the other and their kid didn’t get a fair shot at winning, or when a car would get damaged because it was thrown off of the track at a bump caused by warping. We spent several years designing and developing the BestTrack aluminum track, and believe it to be the fairest and safest track available.”

You can learn more about the Best Track at:

(1) The modified center guide on the BestTrack aluminum track may be the best of both worlds. It is center-guided for compatibility with other tracks, but has the center portion of the guide cleared out to accommodate cars with weights which hang below the bottom of the car.

(2) Royal Ranger, Royal Ambassador, and a few other kits are designed for either center-guide or edge-guide tracks.

(3) The BestTrack aluminum track is made in 7 foot long sections. I recently transported a 4 lane BestTrack in my Ford Explorer. Of course I had to fold down the back seats and slide the front passenger seat all the way forward to get it in.

(4) Ease of assembly on race day was an important consideration for us when we designed the BestTrack aluminum track. Although the initial assembly takes longer, on race day a small team can generally setup a 4
lane track in 15 -20 minutes. This is possible because only four bolts attach the stand, and the lanes are held together with easy to apply spring clips.

From Pinewood Derby Times Volume 3, Issue 3

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(C)2011, Maximum Velocity, Inc. All rights reserved.

Pinewood Derby Car Showcase – February 10, 2012

18 Wheeler – Scott Carpenter

I built this truck for our pack. Its trailer acts as or  “Go/No-go” inspection box too. I have entered it in the Dremel derby design contest and am hoping it does well.

HD Solutions – Andy Holzer

I built this pinewood derby truck for Dorman Products for competition between companies. The truck has bearings on 10 of the axles (the ones that are touching the track). Here is a promotional video for the event:

From Pinewood Derby Times Volume 11, Issue 10

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My son and I had missed a few of the den meetings recently. I was on my way home from work and had called my wife to see what the schedule was for scouts that night. She said it was the pinewood derby. We had not gotten our kit because we had missed the recent meetings, so we had no car to race.

My son really wanted to do this together and I was feeling like I was going to let him down by not having a car to race. So I ran to a local craft store and bought a kit. The kit had a car that was cut to shape but the rest we had to do ourselves. We had only an hour before race time, so we scrambled to get it together.

To make a long story short he won 1st Place in his den and then went on to win 1st Place in the whole Pack. We were both surprised and excited! Who would have thought that would happen? Unbelievable…

From Pinewood Derby Times Volume 3, Issue 2

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(C)2011, Maximum Velocity, Inc. All rights reserved.

The Wheels Go Round and Round – or Do They?

John Lennon wrote that he loved to spend time “watching the wheels go round and round”, and during this pinewood derby season kids and parents will have a similar desire. In households all over this country (and in many other countries as well), kids and parents will be opening a pinewood derby car kit – dumping out the block of wood, the axles, and the wheels. As they inspect the contents, they hope that those raw materials will become a fast and good-looking car.

How many kids will build a car this season? I have no idea, but I am sure that the number of kits manufactured per year for consumption in the United States would boggle the mind. Clearly, kit manufacturing is a high-volume business.

In high-volume manufacturing, price is the name of the game. Organizations look for manufacturers who can produce the required quantity of kits on time, and at the lowest price. Quality is certainly considered, but since the product is considered a ‘toy’ or craft item, precision is not a factor.

This certainly applies to the pinewood derby wheels. To achieve the required volumes, wheels are injection molded in multi-cavity molds (BSA wheels have at least sixteen different mold numbers). The intent is that the wheels produced by the various molds will look and perform similarly; and to the casual eye, this is true. But a closer look reveals that: (1) Each mold produces a wheel with unique characteristics, and (2) No mold produces a ‘perfect’ wheel. Injection molding is great for producing parts cheaply and quickly, but not necessarily with precision.

The variance in wheel characteristics from mold to mold can be determined by measurement and by observation. These characteristics include:

– Diameter variance
– Bore placement
– Bore angle
– Bore diameter
– Tread characteristics
– etc.

Although all of these characteristics can affect performance, this article will specifically focus on the first two characteristics mentioned above.

Diameter Variance – To achieve best performance, each wheel should of course be perfectly round, and all four wheels should have the same diameter. In reality pinewood derby wheels are not perfectly round. Some are close, but others are considerably out of round with an oval or egg-like shape.

Bore Placement – To roll properly, wheels should have the bore placed perfectly in the center of the wheel. Some wheels have the bore virtually perfect, but others have the bore offset several thousandths of an inch.

These two characteristics, Diameter Variance and Bore Placement, together determine the ‘trueness’ of the wheel. A wheel with zero diameter variance, and a perfectly placed wheel bore spins ‘true’. That is, when viewed from the side, the wheel describes a perfect circle as it spins.

The trueness of a wheel can be measured with calipers by making measurements from the wheel bore to the tread. To view the results of caliper measurements on a typical BSA wheel see:

The measurements on this typical wheel demonstrate that the wheel is not true. If used on a car, the body of the car would rise up and down by as much as 0.009 (0.562 minus 0.553) inches on every revolution. Thus, the car would vibrate down the track.

Worse yet, if the balance point of the car was close to the rear axle (best performance), the front wheels would be lightly loaded. An untrue front wheel could cause the front end of the car to slightly lift off the track repeatedly. This could cause several undesirable results including weaving from side-to-side and derailing.

Unfortunately, using a wheel mandrel and some sandpaper will not true a wheel. The sandpaper will remove surface defects, but it cannot remove
material in the proper locations to create a perfectly circular wheel.

In fact, until recently, a machine lathe was the only tool that could true a wheel. However, now a new option exists. Introduced this pinewood derby season, the Pro-Wheel Shaver XT II is essentially an affordable, hand-powered lathe for truing pinewood derby wheels. The shaver mounts on a Pro-Hub tool, the pin of which serves as the center axis for the tool. For photos, and more information about the Pro-Wheel Shaver XT II please Click Here.

If you use the official BSA kit, then there are two alternative ways to get better wheels.

1. If your local race allows lathed wheels, but you don’t want to do it yourself with the Pro-Wheel Shaver, then consider purchasing wheels that have already been lathed. Lathed wheels are available from several sources on the Internet, but for an added benefit, Maximum Velocity offers lathed wheels that are mold number-matched for even better results. For more information, please Click Here.

2. If your local race does not allow lathed wheels, then note that some of the molds produce superior wheels. By using matched wheels from one of the better molds, better results can be obtained. For more information on matched wheels, please Click Here.

If you want to watch your “wheels go round and round” as fast as possible, then consider the characteristics of your wheels. The more true the wheels, the faster they will go round and round!

From Pinewood Derby Times Volume 3, Issue 2

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(C)2011, Maximum Velocity, Inc. All rights reserved.