Pinewood Derby Memory – Hard Work Pays Off

We just completed our pack’s pinewood derby last weekend. My son and I have been building cars for several years. Each attempt was better than the previous one, but still we had always come up as an also ran. This year we dedicated ourselves to having the fastest car at the race. After all, this was his last year for cub scouts so it was do or die!

We purchased several products: the wheel mandrel, hub tool, outer hub tool, and axle polishing kit. With the tools and supplies we had acquired in previous years we had a full suite of tools.

How to use all this? Well to be serious you need some decent test equipment. My son and I built our own one lane test track. While it wasn’t the smoothest and most precise track on earth it did provide for some good testing. I outfitted the track with a timer system I built around a hand stop watch. The watch was good to .001 seconds and was one of the more expensive items ($20.00). I wired in a start switch and rigged up an optical sensor and interface electronics to record the car as it went through the finish lane. It all wired into the start/stop switch in the watch! Remarkably the whole track and timer cost us under $50.00 to build.

The test track allowed us to test wheel combinations, axles, lube types, car center of gravity, etc. We spent almost a week optimizing the final wheel, axle, and weight distribution in our car! My wife was about ready to kill both of us as all we talked about was Pinewood Derby!

Race day came and we passed all the technical checks. Yet we were a bit hesitant to let go of the car! I talked to my son several times about not getting disappointed if we were not the fastest. What was important is that we worked together and had a fun time building and testing the car. Well when it was finally time for the races we were both fairly nervous. The first race pitted us in lane #1 and next to us was one of the known fastest father/son teams from previous years. As soon as the start lever was flipped I could tell we were going to do well. The car rolled true and steady as it slowly pulled away from the other three lanes, beating the nearest car by a full car length. All four runs were the same way. When all was said and done not only did we win the overall race but we set the track record. We were the only car to combine four runs on the 28 foot track in under 9 seconds. The look on my son’s face was priceless. I was shocked and could hardly believe it. The track has seen hundreds of cars and several years worth of races, so you can imagine our surprise.

But when all was said and done, the most important thing in my mind was the lessons we learned. I was able to teach my son that hard work and effort can and does work nearly every time!

Jim Nissen

From Pinewood Derby Times Volume 4, Issue 10

Subscribe to this Free Pinewood Derby E-newsletter

(C)2012, Maximum Velocity, Inc. All rights reserved.

Maximum Velocity Pinewood Derby Car Plans and Supplies

Royal Ranger/ S&W Kits – Getting Top Speed

In terms of kit sales, the official BSA kit is certainly the leader. The runner up is likely PineCar. But after that there are several manufacturers that produce a huge number of kits.

One of these, S&W Crafts Mfg., has been producing kits since 1957. Many kits are sold to Cub Scout packs that choose to not use the official BSA kit, and to YMCA Y-Guides (‘Chule Car’ races – Chule means ‘pine tree’ in the Creek language). Until recently they had the contract for Royal Ranger kits (a boys club sponsored by the Assemblies of God church – see:

The new supplier to Royal Rangers, Amenco, is building the kits to the same specification, so Royal Rangers should continue to see the same type of kit. Here is a photo of the kit:

What is special about this kit? Mainly, the kit uses dowel rods as axle supports, screw-type axles, and narrow wheels. These narrow wheels can lead to very fast cars; however, the axle support system can be a challenge. So, this article will provide some tips for overcoming the challenges of this kit and help you achieve top speed.

To accommodate the dowel rod axle supports, the block is equipped with two 3/8″ diameter, half-round slots. The slots are located about one inch from the ends of the block, thus the wheelbase is longer than most kits on the market. Make sure to load the ballast weight towards the rear of the car (which can be either end; but if you choose to retain the cutout in your design, note that it is offset towards one end of the block).

The dowel rod slots cut into the bottom of the car determine how the dowel rods will mount on the car. One of the first steps in building a pinewood derby car is to inspect the slots to see if they are square with the block, and are consistently cut to the same depth. The best way to check if the slots are square to the block is to use a tool called a ‘Square’.

But if you don’t have a square, align the long side of a piece of note book paper with the side of the car and see if each slot aligns with the top of the paper.

The depth of the slot can be measured with a ruler. Check the depth of both slots on the left side and on the right side of the block.

If either slot is not square, or if the slot depth is not the same at all our points then the block needs to be replaced. You can certainly just get a new block, but dowel slots can be created on a blank block if you have access to the following:

– Drill press

– 3/8 inch Brad Point or Forstner drill bit

– Clamp

– 2 blank blocks (or one blank block and the defective kit block)

Lay the blank blocks on their sides on the drill press table with the bottoms together (or the top of the defective kit block). Then carefully clamp the blocks together, making sure that the ends match up. Mark the desired drilling locations with a pencil in the joint between the blocks.

Place a flat board under the clamped blocks, set the drilling depth to go though the blank blocks, then set the drilling location. The drill bit must be positioned such that the tip of the bit aligns exactly with the joint between the blocks.

Now start the drill press, hold the blocks firmly, and drill the two holes. After unclamping the blocks, both blocks will have accurate dowel rod slots.

The dowel rod axle supports are essentially 3/8 inch dowel rod pieces, cut to length, and pilot-drilled on the ends.

Pilot Holes

All four pilot holes should be drilled exactly in the center of the dowel rod, and should be drilled parallel with the side of the dowel rod. Use a ruler to check if the holes are drilled in the center of the dowel rods, then insert a round toothpick (or something else that is the same size as the hole, such as a small nail) into the holes to see if the holes are drilled straight. If the toothpick appears to stick out of the hole at an angle then the holes are not straight.

If the holes are not accurate, then they need to be replaced or corrected. An accurate way to correct the pilot holes is to use a Pro-Body Tool (link), a guide for re-drilling accurate axle holes with a hand drill into dowel rod axle supports.(1)

Beveled Ends

The wheels on the kit have a dome shape-sidewall which minimizes the contact area with the axle supports. However, slightly beveling the end of the axle support will further minimize contact with the side of the wheel. This bevel can be created with a piece of sandpaper mounted on a piece of wood, and a hand drill.

1. Clamp the drill to a work surface.
2. Insert the axle support into the chuck of the drill.
3. Start the drill and apply the sandpaper to the edge of the dowel rod. Create a bevel, but be careful to not shorten the axle support.

The bevel should be very slight. Do not ‘sharpen’ the end of the dowel rod like a pencil as it will weaken the support and could cause binding in the wheel bore.

Next, the dowel rod pieces must be glued into the slots on the bottom of the block. When doing so, make sure that the axle supports are centered such that an equal amount of the axle support extends from each side of the block.

The axles in this kit are round-head wood screws. For best performance, mount a screw in the chuck of a drill (which has been clamped to a work surface), and use a small file to remove any burrs under the axle head, and to slightly bevel the head. Avoid creating a significant bevel as it can cause binding in the wheel bore.

Next, polish the non-threaded part of the axle shaft with an axle polishing kit or use your favorite polishing method.

The wheels on the Royal Ranger/S&W kit are narrow and are made of a plastic which is readily shaped. This is good since the wheels are generally not perfectly round, and need to be trued. If you have access to a machine shop, then a lathe can be used to accurately true the wheels. However, since most people do not have access to this type of machine, the Pro-Wheel Shaver does an excellent job of truing these wheels.(2)

Please note that a 1/8″ bushing IS REQUIRED for these wheels.

Of course as with any pinewood derby car, good lubrication is essential. Make sure to thoroughly lube the wheel bore, and rub some graphite on the end of the axle supports.

Royal Ranger/S&W kits are a unique kit, and present some fun challenges. I encourage you to rise to the challenge and create a car that reaches Maximum Velocity!

(1)The Pro-Body Tool for Royal Rangers can be found here:

(2)The Pro-Wheel Shaver XT can be found here:

From Pinewood Derby Times Volume 4, Issue 10

Subscribe to this Free Pinewood Derby E-newsletter

(C)2012, Maximum Velocity, Inc. All rights reserved.

Maximum Velocity Pinewood Derby Car Plans and Supplies

Raising Boys

Editor’s Note: This has nothing to do with the pinewood derby, but since you likely have a boy or two I thought you would enjoy.

For those with no children – this is totally hysterical! For those who already have children past this age, this is hilarious. For those who have children this age, this is not funny. For those who have children nearing this age, this is a warning. For those who have not yet had children, this is birth control.

Things I’ve learned from my Boys (honest and not kidding):

1. A king size waterbed holds enough water to fill a 2000 sq. foot house 4 inches deep.

2. If you spray hair spray on dust bunnies and run over them with roller blades, they can ignite.

3. A 3-year old boy’s voice is louder than 200 adults in a crowded restaurant.

4. If you hook a dog leash over a ceiling fan, the motor is not strong enough to rotate a 42 pound boy wearing Batman underwear and a Superman cape. It is strong enough, however if tied to a paint can, to spread paint on all four walls of a 20×20 ft. room.

5. You should not throw baseballs up when the ceiling fan is on. When using a ceiling fan as a bat, you have to throw the ball up a few times before you get a hit. A ceiling fan can hit a baseball a long way.

6. The glass in windows (even double-pane) doesn’t stop a baseball hit by a ceiling fan.

7. When you hear the toilet flush and the words “uh oh”, it’s already too late.

8. Brake fluid mixed with Clorox makes smoke, and lots of it.

9. A six-year old boy can start a fire with a flint rock even though a 36-year old man says they can only do it in the movies.

10. Certain Lego’s will pass through the digestive tract of a 4-year old boy.

11. Play dough and microwave should not be used in the same sentence.

12. Super glue is forever.

13. No matter how much Jell-O you put in a swimming pool you still can’t walk on water.

14. Pool filters do not like Jell-O.

15. VCR’s do not eject “PB&J” sandwiches even though TV commercials show they do.

16. Garbage bags do not make good parachutes.

17. Marbles in gas tanks make lots of noise when driving.

18. You probably DO NOT want to know what that odor is.

19. Always look in the oven before you turn it on; plastic toys do not like ovens.

20. The fire department in Austin, TX has a 5-minute response time.

21. The spin cycle on the washing machine does not make earthworms dizzy.

22. It will, however, make cats dizzy.

23. Cats throw up twice their body weight when dizzy.

24. 80% of Men who read this will try mixing the Clorox and brake fluid.

25. 85% of Women will pass this on to almost all of their friends, with or without kids.

Anonymous Mother in Austin, Texas

From Pinewood Derby Times Volume 4, Issue 9

Subscribe to this Free Pinewood Derby E-newsletter

(C)2012, Maximum Velocity, Inc. All rights reserved.

Maximum Velocity Pinewood Derby Car Plans and Supplies

Getting Great Results with Pro-Tools – Part 2

In a previous article (Volume 4, Issue 6) we discussed how to get the most benefit from three of the Pro-Tools(1): the Pro-Hub Tool, the Pro-Axle Press, and the Pro-Body Tool. This article will continue by discussing the Pro-Bore Polisher, the Pro-Wheel Mandrel, and the Pro-Wheel Shavers.

One of the most useful tools in building a pinewood derby car is a Wheel Mandrel. This tool is used to mount a wheel in the chuck of a drill to facilitate polishing the tread.

The Pro-Wheel Mandrel has several features that differentiate it from a standard mandrel:

1. Coned head to improve centering the wheel on the mandrel.
2. Knurled thumbscrew to simplify and speed-up mounting and removing wheels (the standard mandrel requires a flat blade screwdriver to mount and remove wheels).
3. Offset on mandrel body allows mounting of a BSA wheel with the spokes facing the drill. This simplifies polishing the inside edge of the wheel.

For best results when using a mandrel, first square the hub of the wheel on the side which will face the mandrel body. If the inside hub will face the mandrel body, then use the Pro-Hub Tool to square the inside wheel hub. If the outside hub will face the mandrel body, then use the Pro-Outer Hub Shaver to square that surface (BSA wheels only).

Note that the purpose of using a wheel mandrel is to mount a wheel in a drill for sanding and polishing the tread surface. This setup is not intended for ‘truing’. Wheel truing requires a tool with a mounted blade, such as a lathe or the Pro-Wheel Shavers.

The Pro-Wheel Shaver XT provides the most cost effective way to create sets of perfectly round wheels from a standard molded wheel. With a little practice, the Pro-Wheel Shaver XT will create wheels that are accurate to one-thousandth (0.001) of an inch. This is generally better than wheels which are trued on hobby lathes, and approaches the quality of wheels trued on computerized lathes.

Why are round wheels so important? As the car travels down the track, out of round wheels cause the axles/car body to rise and fall. At slow speeds this causes very little trouble. But at top speed, the oscillation will cause the car to vibrate (which slows it down) and pull to one side (causing excessive contact with guide rails). Both of these are speed busters.

The Pro-Wheel Shaver XT will not only true the tread surface, but will also true the inside edge of the wheel. The most perfectly aligned cars will still touch the guide rail one or two times on the way down the track. If the inner edge of a wheel is not true, the contact may cause the car to kick away from the rail very quickly. Often this causes the car to begin zigzagging back and forth down the track, greatly diminishing speed. With trued inside edges the guide rail contact is softened resulting in a straighter run.

For best results, make several passes to get all four wheels trued to the same diameter. When changing wheels, to improve accuracy leave the blade at the previous setting and loosen the bolt holding the shaver to the Pro-Hub Tool. Rock the shaver back, remove and replace the wheel, then re-tighten the bolt. This ensures that the wheels are trued to the same diameter and minimizes cross-cuts on the tread (which occur if the wheel is removed without loosening the bolt. If there is not enough ‘play’ to allow the shaver to be rocked, rotate the wheel in the opposite direction while removing.

Make sure to make a final pass on the wheels to remove all possible material. These final turns will remove fine, fuzzy plastic shavings, which improves the finish on the wheel.

The bore on an injection molded wheel typically has pits and bumps which are visible at magnification. These defects will reduce the spin time of the wheel.

The Pro-Bore Polisher is used to polish the wheel bores, resulting in a smooth, virtually defect free bore surface. The polisher uses a pipe cleaner as the polishing brush, and an industrial grade plastic polish as the abrasive. The polisher holds the pipe cleaner stiff and straight, improving the pressure on the wheel bore.

For best results run the drill on a slow speed, and do not put a wheel on the polisher while the drill is spinning. Do not use a Dremel-type tool, as the high RPM can damage the bore.

We wish you the best when using your Pro-Tools. If you have any tips or tricks that you have learned regarding these tools, please send them to me and I will share them in future editions of this newsletter.

(1) The Pro-Tool line, manufactured by DerbyWorx includes:

Pro-Axle Press
Pro-Body Tool
Pro-Hub Tool
Pro-Outer Hub Shaver
Pro-Bore Polisher
Pro-Wheel Mandrel
Pro-Wheel Shaver XT

The Pro-Tools are available at many local and on-line hobby stores, including Maximum Velocity.

From Pinewood Derby Times Volume 4, Issue 9

Subscribe to this Free Pinewood Derby E-newsletter

(C)2012, Maximum Velocity, Inc. All rights reserved.

Maximum Velocity Pinewood Derby Car Plans and Supplies

Pinewood Derby Memory – Crowd Favorite

Last year my son was a Bear and it was our third year competing in the pinewood derby. After talking with him, he decided he wanted to build a really fast car but wanted to have “Sponge Bob” involved in it somehow. The previous years he had done okay winning his Tiger level and placing third in his Wolf level.

So we ordered some of your speed supplies and we went to work. We kept the car design simple, just a slightly modified wedge. We pirated some parts from one of those mini remote control cars you can get at Radio Shack and added them to the car.

The best part was when the racing started all of the Scouts (this is no exaggeration) began chanting “Sponge Bob – Sponge Bob – Sponge Bob” every time his car raced. To watch his eyes when this happened was magical. My son is a little shy and to have everyone cheering for him was a real surprise to him.

He raced 9 different times last year and never lost a race. There was only one car faster but it was disqualified (the wheel base was extended and the wheels were shaped) so he won the overall and the Bear level.

I really would not have cared if he came in last because he was the center of attention for a short period. He really didn’t care how the car did either; he was just tickled to be that popular.

This is what scouting and pinewood derby is all about – working together to build a car and create a great memory.

David Brymer

From Pinewood Derby Times Volume 4, Issue 8

Subscribe to this Free Pinewood Derby E-newsletter

(C)2012, Maximum Velocity, Inc. All rights reserved.

Maximum Velocity Pinewood Derby Car Plans and Supplies

You Know You’re a Pinehead if …

You know you’re a Pinehead if …

1) You believe Pinewood Derby Racing should be an Olympic event.
2) You have asked to be buried in a Pinewood coffin shaped like your derby car.
3) If your derby car coffin (above) will be tungsten weighted so it’s COG is 1″ above your rear’s axle.
4) If family planning means staging the births of your children so one starts the derby as one finishes.
5) You’ve recently purchased stock in Krytox.
6) 2 or more of your fingers are permanently stained with graphite with molybdenum.
7) You’ve named your children to intentionally have the initials PWD.
8) If you refer to the after life as “that giant aluminum track in the sky”.
9) If you’ve ever had a vivid dream of breaking the 2.0 second barrier and woke up not knowing if the dream was real or not.
10) If you’ve ever thought of developing a snack food that looks like Maximum Velocity’s outlaw wheels.
11) You’ve watched online videos of several heats of a WIRL race, and you’ve never entered a car.

Interpreting Your Score:
1-3 Please, join Pinewood Anonymous’ support group.
4-6 With strong medicine and intense therapy; well, sorry, there really isn’t much hope.
7-10 Maybe you could be on a reality show, “Real WIRL’d.”
11 Congratulations, you are the new Pinehead Poster child.

James Baker (with one addition from an unknown author)

Editor’s Note: WIRL stands for ‘Woodcar Independent Racing League’. Visit them at:

For additional indications of ‘pineheadedness’, please visit:

If you have some additional ‘pinehead’ indications not listed in this article or at DerbyTalk, please send them to me and I’ll include them in a future article. Please include your name.

From Pinewood Derby Times Volume 4, Issue 7

Subscribe to this Free Pinewood Derby E-newsletter

(C)2012, Maximum Velocity, Inc. All rights reserved.

Maximum Velocity Pinewood Derby Car Plans and Supplies

Getting Great Results with Pro-Tools – Part 1

For what are the best automobiles noted? Luxury? Probably. Power?

Certainly. Precision-built components and assemblies? Absolutely. The engine, transmission, suspension, etc. must be manufactured to high tolerances. There is no room for sloppy parts and assemblies.

Similarly, using precision parts is a key component of building a high-performance pinewood derby car. Although they are significantly simpler, the principle is the same: wheels, axles, and alignment must be precisely machined and installed for top performance.

At one time, the average pinewood derby builder could not achieve a high level of precision unless they had access to a machine shop. Thus, only the fortunate few could tune up their cars with precision, and these few typically dominated on the track. But now, with the advent of the Pro-Tool(1) line of components, a significant level of precision can be achieved by anyone.

Today’s article will share insights into three of the Pro-Tools, while the remaining Pro-Tools will be discussed in a future article. Much of the material in this section was contributed by Bill Launius, the inventor and manufacturer of the Pro-Tool line of products.

The Pro-Hub Tool is used to prepare the inside wheel hub and the wheel bore. It has three primary functions:

1. Square the inside wheel hub to the wheel bore – This ensures that the wheel properly mounts on a wheel mandrel, and eliminates excess plastic flashing remaining from the injection molding process. This flashing is readily apparent on specific BSA wheel molds.

2. Cone the inside wheel hub – This minimizes the contact patch with the car body, thus reducing the braking effect when the wheel hub touches the car.

3. Reaming wheel bores – Some wheels are molded with a bore that is too small for the wheel mandrel. The Pro-Hub tool will ream out undersized

But in addition to these primary functions, the Pro-Hub tool also provides the following benefit:

4. Sizing wheel bores – The pin of the Pro-Hub tool can be used to identify four wheels with a specific bore sizes. This is an important step in alignment because wheels with different bore sizes, even if they are lathed round, will not have the same measurement from tread to bore.(2) Thus, the wheels will not sit evenly on the ground, leading to alignment problems.

5. Graphite application – The coned end of the Pro-Hub Tool can be used to rub graphite into the inside wheel hub. Simply squirt graphite into the coned end, slide on a wheel (hub side in) and twist.

The Pro-Hub tool now has a companion tool, the Outer Pro-Hub Tool. This new tool is used with the Pro-Hub Tool to true the outer wheel hub to the bore.

Many pinewood derby kits, such as BSA, use nails for axles. These axles are not manufactured to a high tolerance (they’re just nails!), so they are generally not perfectly straight. Since top-performance requires precision parts, these axles must be straightened. Otherwise, the axle defects will affect the speed of the car and the alignment of the car.

How do bent axles affect speed? The fastest axle/wheel combination is a neutral position in which the wheel ‘floats’ back and forth between the axle head and the car body. This minimizes friction by avoiding constant contact with either the nail head or the car body, and ensures that the weight of the car is evenly dispersed on the wheel bore. A bent axle will only contact the wheel bore in limited spots, creating binding in the wheel bore, and causing the wheel to be forced to constantly rub either the axle head or the car body.

The Pro-Axle Press will:

1. Straighten nail-type axles – With just a hammer and firm surface, the Pro-Axle Press will create straight axles.

2. Square the nail head – Oftentimes the nail head is not square to the shaft. The Pro-Axle Press quickly corrects this flaw.

3. Facilitate creating a raised wheel – Three-wheel cars are faster than four-wheel cars. One way to raise a wheel off the ground is to bend one of the front axles upward. The Pro-Axle Press serves as a clamp to hold an axle for a quick bend with a hammer.

Precision alignment is a critical factor for pinewood derby performance. While methods exist to correct alignment, creating a car that requires minimal alignment correction is the goal. A significant area that affects alignment is axle mounting. Whether slots or drilled holes are used, the axles must be inserted into the car parallel to each other.

The Pro-Body Tool facilitates correct alignment by serving as a drilling guide for axle holes, or for pilot holes in axle slots. Specifically,

1. Accurate axle holes – The Pro-Body Tool places the axle holes perpendicular to the center line of the car, thus ensuring parallelism between the axles, front to rear.

2. Accurate placement – The Pro-Body Tool locates all of the axle holes at the same height on the body (optionally with one wheel raised), ensuring axle parallelism from top to bottom.

3. Minimizes drill bit deflection and run-out – The Pro-Body Tool guides the rather thin #44 drill bit to minimize deflection due to density variance in the wood. In addition, most drill presses have some run-out (free play in the spindle assembly) which reduces accuracy. By using the Pro-Body tool, run-out is minimized.

Note that Pro-Body Tools are available for various car kits including BSA, PineCar, Royal Rangers/S&W, and Awana.

I hope that these thoughts will help in using the Pro-Tools. If you have any tips or tricks that you have learned regarding these tools, please send them to me and I will share them in future editions of this newsletter.

(1) The Pro-Tool line, manufactured by DerbyWorx includes:

Pro-Axle Press
Pro-Body Tool
Pro-Hub Tool
Outer Pro-Hub Tool
Pro-Bore Polisher
Pro-Wheel Mandrel
Pro-Wheel Shaver II
Pro-Wheel Shaver XT

The Pro-Tools are available at many local and on-line hobby stores, including Maximum Velocity.

(2) If the lathed wheels are mold-number matched, such as those by Maximum Velocity, then the bore sizes are the same, so wheel matching is not required.

From Pinewood Derby Times Volume 4, Issue 6

Subscribe to this Free Pinewood Derby E-newsletter

(C)2012, Maximum Velocity, Inc. All rights reserved.

Maximum Velocity Pinewood Derby Car Plans and Supplies

Reader Submitted Speed Tips

Here are a few speed tips submitted by our readers:

Alex Ezell – Use a tool called a caliper to find thick axles. Then polish them super smooth. But don’t remove more material than necessary.

Bob Dahlberg – Build two cars. The second one will be faster.

Jerry Lencoski – To make the bottom of the car totally smooth after the axles are inserted and aligned, I cut a sliver of popsicle stick, glue it into the slot, and sand it smooth. This cuts down on the drag under the car.

Matt Bierek – At many derbies, officials offer to lube the cars for the participants at check in. If yours is one, politely decline since, once lubed, you will not get the proper break in before the races begin. This occurs at our race, and it is clear from the heat times that all participants who requested lubes did better in race four than in race one.

From Pinewood Derby Times Volume 4, Issue 5

Subscribe to this Free Pinewood Derby E-newsletter

(C)2012, Maximum Velocity, Inc. All rights reserved.

Maximum Velocity Pinewood Derby Car Plans and Supplies

Rule Gripes

I receive lots of questions and comments from our readers about rules.  Many times the person is asking me for the rules for their race, or for a clarification on a point. Sometimes, the person is griping about the rules, especially when the race leader appears to them to be misinterpreting the local rules.

In these cases, I can’t do much more than lend a sympathetic ear. Local rules are out of my control, and I certainly can’t jump in the middle of a rule dispute. But during these times I certainly do wish that the local race leaders would take the time to document a clear set of rules. So much miscommunication, grief, griping, and anger would be mitigated by giving a clear set of rules to the race participants well before the race event. (1)

But there is a more fundamental question that needs to be answered when establishing rules. Even if the rules for the local race are clearly documented, a valid question is ‘Why?’ Why is a particular technique allowed/banned? What is the rationale for allowing (for example) an extended wheelbase? Why do we need to have 4 wheels on the ground? Of course this list goes on.

In today’s article I would like to explore several common areas of pinewood derby design that are oftentimes regulated, and offer some guidance as to whether these design techniques should or should not be restricted.

The purpose for rules is to make sure that the cars entered in the race:
1. Will run properly on the track (proper width, height, etc.)
2. Will not damage the track (too heavy, improper materials)
3. Maintain a level of equity. These arbitrary limits – such as the five ounces maximum weight – are imposed to limit the range of options, thus maintaining a level of competitiveness.
4. Only use techniques which are commonly available to the other entrants.

Furthermore, the rules need to be in line with the rules of parent organizations when participants at the local level will be moving on to district level races.

Let’s take a closer look at several rule areas

There are many advantages to longer wheelbase cars (see Volume 2, Issue 6 – “Modifying the Wheelbase”). So, should extended wheelbase cars be allowed in all races? Let’s look at the criteria from above:

1. Yes – the car will run properly.
2. Yes – no damage to track.
3. Yes, required for equity. A long wheelbase car has a distinct advantage over shorter wheelbase cars.
4. Yes – anyone can extend the wheelbase using a hand drill(2) or drill press. But some expense is involved.

Disallowing extended wheelbase cars is a limit set to maintain competition. If the local club allows wheelbase modification, then this should be documented in the rules so that participants know that they are allowed to modify the wheelbase. Also, the means to extend the wheelbase should be made available to all participants at a workshop. By the way, some organizations run two classes of cars: “Stock” – standard wheelbase only, and “Open” – Extended wheelbase allowed.

Many different lubes have been successfully used on pinewood derby cars, including dry lubes (graphite and PTFE), liquid lubes (Krytox 100 and Silicon), and some unusual ones (Pledge furniture polish, Armor All, and
Talcum powder).(3)

1. Yes – the car will run properly.
2. Yes and No – if used properly none of these lubes will cause damage. But if used to excess, many of the lubes can stain the track (including graphite).
3. No, not required for equity. Several different lubes can be used with reasonable success.
4. Yes – anyone can select an alternate lube.

Limiting the lube to a particular type is an arbitrary decision. Certainly, to protect the track the rules must specify that excess lube be removed before the car is turned in. But limiting the lube to one type is not necessary. Different lubricants are widely available, and in fact, the choice of lube is an area where human ingenuity comes into play!

Having three wheels on the ground can be a speed advantage. But beyond this, it is much easier to build a car with three wheels on the ground than with four! Even when four wheels touch the ground, normally three of the wheels hold the weight of the car while the fourth wheel just barely touches.

1. Yes – the car will run properly.
2. Yes – no damage.
3. No, not required for equity. Although there can be an advantage to running a three-wheeled car, the amount of advantage will depend on the design of the car.
4. Yes – in fact it is easier to run three than four on the ground.

Limiting the car to four wheels on the ground is arbitrary. Since it is easier to implement, I strongly recommend allowing three wheels on the ground.

Many car kits are equipped with wheels that are badly out of round. To
improve the performance, the wheels can be trued.

1. Yes – the car will run properly.
2. Yes – no damage.
3. Yes, required for equity. Rounder wheels are faster.
4. Yes – anyone can true wheels (4). But some expense is involved.

Limiting the car to non-trued wheels does serve to maintain competition. However, since many wheel types can be severely out of round (such as BSA), groups should consider offering the means to true wheels at a workshop.

The speed of the car can be improved by reducing wheel mass through tread reduction. This can be done in many ways including drilling holes in the wheels, and by narrowing the tread.

1. Yes – the car will run properly.
2. Yes – no damage.
3. Yes, required for equity. Some modifications can greatly improve speed.
4. No – although they can be purchased, accurately modifying the geometry of a wheel requires either special machinery and/or extensive trial and error.

Since wheel modification is beyond the ability of many race participants, I recommend limiting wheel modification to ‘Open Competition’ races.

Aftermarket wheels are axles can improve the speed of the car.

1. Yes – the car will run properly.
2. Yes – no damage.
3. No, aftermarket speed axles are not necessarily faster than well-prepared kit axles.
4. Yes – Aftermarket parts are available, but an expense is involved.

The purpose of providing a kit is so that each participant uses the same basic materials. However some kits provide axles that require extensive work.(5) In these cases groups should consider offering aftermarket axles to all participants.

There are certainly other rules that should be reviewed to determine whether there is a basis for the restriction. I encourage all race leaders to thoroughly review the local rules and make modifications where needed.

(1) In Volume 2, Issue 2 – “It’s the Law! – A Sample Rule Set for Your Pinewood Derby”, I provided an outline for a complete set of rules. Just fill in the blanks for your organization.

(2) The Pro-Body Tool is a drilling guide to accurately drill axle holes with a hand drill. You can find it at:

(3) I do not personally vouch for any of these products except graphite and Krytox 100. For more information on these products, see:

(4) The Pro-Wheel Shaver is a device for truing wheels. For more information see:
In addition, trued wheels are available from many sources including Maximum Velocity.

(5) One of my pet peeves is the nail axles in the BSA kits. Removing the burrs is a difficult process for many people. Certainly BSA could include axles without burrs at little to no cost increase. But until such a time, people will continue to purchase aftermarket axles. An alternative is our Official BSA Speed Axles. For more information see:

From Pinewood Derby Times Volume 4, Issue 4

Subscribe to this Free Pinewood Derby E-newsletter

(C)2012, Maximum Velocity, Inc. All rights reserved.

Maximum Velocity Pinewood Derby Car Plans and Supplies