Thursday, October 16, 2014

PINEWOOD DERBY CAR SHOWCASE

Let's kick off the new season with some very unique cars that were submitted at the end of last season.

'56 Ford Pickups - Lyle and Ben Leis


2009 was the last year for my son to compete in the Pinewood Derby. He has done well in the past with a variety of cars, but for his last year, he wanted to build a pickup truck. We bought a '56 Ford Step side die cast car to copy and scratch built from there. Since we only had two weeks to get them completed, it was an ambitious project.

In the past, I have built several exhibition cars while my son built more conventional cars. Using the profile of the die cast car, we started with a sketch of the top and side view of the car using the Boy Scout wheelbase and overall dimensional requirements. Since this project required a hollow body and woodcarving skills, we each built a truck with me working step by step ahead of my son while he followed/copied my work on his truck. The original Pinewood block was cut down to 3/8 inch thick and thin pine stock was added to form the bed and truck cab. The panels were carved and sanded to final shape followed by many coats of primer with sanding between. Since the colors are transparent, a silver base coat was used under the transparent top coats. The hollow lead tanks in the rear of the beds are formed from stick on wheel weights and final weight adjustment was made using lead shot. A wood screw between the truck bed and the cab secures the cab to the chassis.

Although the truck didn't do well in the race due to aerodynamic considerations, for the first time my son has taken an interest in woodcarving, so I consider it a huge success. His truck also won a trophy for the Most Unique design, although the judges were probably not aware of the hollow cab and woodcarving required for the build.

The first photo shows the cab off and the second shows the underside of the cab and how it was scratch built from pieces of pine before final shaping and painting. My son's truck is blue and mine is red.

Monster High - Damon and Addison Krall

This Monster High-heeled Shoe car was built for fun for my daughter Addison to beat all the boys at her brother's derby on race day. The speedy razor wheels gave this car a nice boost. The unique design got
lots of attention.

Landspeeder - Dennis Bjorn

While sorting through my adult son's Legos I found the instructions for a Lego version of Luke Skywalker's Landspeeder. After consulting with Obi Wan and Luke we decided my speeder could only have one seat, so it wouldn't interfere with the cars in the other lanes. Obi Wan found a guy that could machine the three-spoke wheels.

From Pinewood Derby Times Volume 14, Issue 1

Subscribe to this Free Pinewood Derby E-newsletter

(C)2014, Maximum Velocity, Inc. All rights reserved

Maximum Velocity Pinewood Derby Car Plans and Supplies

Friday, October 10, 2014

Revisiting the Balance Point
By Randy Davis

In my first few pinewood derbies I had no concept of setting a balance point (also known as COG or CG). I knew that the car needed to weigh five ounces, so I added weight to the middle of the car and raced. We had mixed results (most everyone else didn't know what they were doing either). But there was one family who had very fast cars. From that Dad, I learned about rear-weighting (and about using a quality graphite). So after that we started rear-weighting the cars.

When I wrote the first few editions of our "Speed to the Finish" booklet (for free distribution at our local club - not for sale) I didn't even mention a balance point. But in the first edition that went on sale, I gave a range of 3/4 to 1-1/4 inches as the target balance point.

Although I don't believe my booklet really set the standard, somehow a 1-1/4 inch balance point became the de facto oral standard for the balance point. Even today, I regularly get calls from folks who state that they "set the balance point of their car to 1-1/4 inches, which is the recommended position".

Is/was a 1-1/4 inch balance point the best position? Has anything changed to cause us to rethink the best balance point? Let's take a deeper look.

MEASURING THE BALANCE POINT
The balance point of a pinewood derby car can be easily located as follows: (1) set a balance stand (or a ruler on its long edge) on a table and (2) lay the car (with wheels and axles in place) on the device as shown in Figure 1. Move the car forward or backward until it balances on the ruler. The balance point is the distance from the
center of the rear axle to the point at which the car balances.




Figure 1 - Locating the COG

BALANCE POINT AND STABILITY
The balance point directly affects the stability of the car. If a car has a balance point that is too aggressive for the track, the car will generally be very fast on the hill, but will become unstable on the flat portion of the track and will exhibit a rapid left-right motion known as the "death rattle". To correct the instability, either Rail- Riding(1) alignment must be implemented (or increased), or the balance point must be moved forward.

THE 1-1/4 INCH "STANDARD"
Likely, the 1-1/4 inch balance point standard came from repeated posting of this number on web sites and in speed tip booklets. At the time when this number became a standard (the year 2000 or earlier) most tracks were made of wood and were not as smooth and precise as modern tracks. So the 1-1/4 number was aggressive enough to provide good performance, but conservative enough to provide stability on the vast majority of tracks. Another factor to consider is that tungsten was not readily available for car weighting until about 2003, so making a car with a more aggressive balance point was a challenge for most car builders. So, all things considered, at the time the 1-1/4 inch balance point was a good target number for the vast majority of car builders.

NEWER TECHNOLOGY
But then, as always, technology changed and pinewood derby racing reaped some of the benefits. First, aluminum tracks came on the market, followed quickly by tungsten weight. Now, cars could be more easily rear-weighted, and smooth tracks were available to improve stability. Finally, the Rail-Riding alignment method was introduced to the pinewood derby community, which provided increased stability for cars running with aggressive balance points.

NEW BALANCE POINT STANDARD
So, we are now at a time when the 1-1/4 inch standard is a bit dated. When people ask, I now give the target balance point numbers listed below. Please recognize that these numbers are for people that generally do not have tracks to test on and have one shot at racing. Certainly, you can be more aggressive if you have access to a track, and time to fine tune the car.

Wood Track, no alignment consideration: 1-1/4 inches
Wood Track, Rail-Riding: 1 inch
Aluminum track, no alignment consideration: 7/8 inch
Aluminum track, Rail-Riding: 3/4 inch

There are other factors that affect these target numbers. For example, tracks of 50 feet or longer, and very rough tracks require a less aggressive balance point. But if the track is reasonably smooth and of a standard length, these target balance point numbers work well for the majority of car builders.

CONCLUSION
Certainly there are a lot of factors that affect the positioning of the balance point. However, I hope that this article provides some food for thought, and helps reset the standard for setting the balance point. But I am sure that I will keep getting calls from folks stating that they "set the balance point of their car to 1-1/4 inches, which is the recommended position".

(1) Rail-Riding is an alignment technique that generally improves performance. In November, there will be a complete article on Rail-Riding.

From Pinewood Derby Times Volume 14, Issue 1

Subscribe to this Free Pinewood Derby E-newsletter

(C)2014, Maximum Velocity, Inc. All rights reserved

Maximum Velocity Pinewood Derby Car Plans and Supplies

Friday, October 03, 2014

PINEWOOD DERBY CAR SHOWCASE

Today's showcase cars are from Chad Thorvilson.

I have been involved in the Cub Scouts since my son, Ryan, first started in 2000. The second year of the pinewood derby I made a new four lane Formica track for the pack. He is now in Boy Scouts, and he and I still help run the track. We have always enjoyed making cars and other projects in the shop. We no longer race, but we still make cars every year. The last few years I have been making trick cars.



This white and red car has a trigger on the bottom that releases the sides and roof. A small wedge is put on the track and when the car crosses it the sides and roof pop off.




The light blue speckled car leaves the cab behind as the tires and frame go down the track.



This blue car has a piece of radio antenna that I pull out to hold the competition back.




The red and blue car has a nose attached to a radio antenna. I pull out the nose and tell the boys that I will beat them by this much.

I also have a car with a small motor geared to the tire to make it run very slow (not shown).



Here is my fan powered car and string/motor car.


We have also made some nice cars. We were finalists in the Lowes/Dremel contest one year and grand prize winners the last year they had the contest.

We look forward every year to the pinewood derby and working in the shop together. I get excited when the first Pinewood Derby Times arrives in my inbox.

From Pinewood Derby Times Volume 8, Issue 7

Subscribe to this Free Pinewood Derby E-newsletter

(C)2014, Maximum Velocity, Inc. All rights reserved

Maximum Velocity Pinewood Derby Car Plans and Supplies

Friday, September 26, 2014

PINEWOOD DERBY MEMORY
Ugliest Car in Derby History


When I was a young boy in cub scouts, derby time came. So like many other kids my dad helped me build my car. Because of my health problems, my dad worked two and sometimes three jobs, so spare time was a rare thing. As a young kid I didn't understand why it seemed like I was having to build the car on my own (besides, I wasn't doing such a good job of it). I didn't know it then, but I had the very best in fathers. He helped me every chance that he had, but like I said, his time was in short supply. Anyway, the car finally was built and ready for paint. I was sort of on my own again for this, and I really messed it up bad. My dad saw it and said it wasn't so bad, he would just sand it off and I could start over again. Nobody told me how to paint though, so it came out worse the second time around, and I also had run out of paint. As ugly as it was, things got even worse.

Race day came and I wasn't going to take that ugly car to the derby. I am not sure which of my two older sisters or my mom came up with the idea that fingernail polish might cover the bad paint job -- and that it dried really quick. Just as soon as I got home from school I started trying to make things better with some horrible color of fingernail polish that one of my sisters had given me. It got worse and worse. I kept piling on more of that thick gooey stuff. The polish would dry and I would put on more. It looked horrible. Nothing more could be done at that late date and even though I was very unhappy with the final results, we had to go race it anyway.

One of the first things I can remember when we got to the race was the cars that two friends of mine had brought. They were absolutely beautiful, formed so well and the paint was perfect on both of them. But both of those cars were eliminated before the race because that had not complied with rules and had used really trick slot car wheels instead of the plastic wheels required by the rules.

During the race, my car won races up to one of the very last rounds. The little ugly car smoked so many others, and not by just a little. I was so proud of it then even though it was hard to look at. This is not the end of the story, although I guess it could be.

Years later, derby time came around for one of my nephews. I helped him build his car (in other words I did almost all of it myself). It was perfect, sanded with 1000 grit paper, weighted perfectly on a digital scale, and the paint was so perfect. The car turned out great.

Race day came for my nephew and as we were having the cars inspected before the race someone doing the inspections mentioned to the crowd that these were some very good-looking cars that the "boys" had built. Then he looked right at me. He knew that this was my creation, not my nephews.

The race came and went and we were almost happy with the results. It turns out that the fastest car that night turned out to be the second ugliest car in derby history. Right behind the one I built when I was young.

Terry Graham

From Pinewood Derby Times Volume 8, Issue 6

Subscribe to this Free Pinewood Derby E-newsletter

(C)2014, Maximum Velocity, Inc. All rights reserved

Maximum Velocity Pinewood Derby Car Plans and Supplies

Friday, September 19, 2014

PINEWOOD DERBY CAR SHOWCASE

Chilly Willy - Rob & Blake Overton

Attached is a picture of my son, Blake's ice cream sandwich car which he named "Chilly Willy". It won crowd favorite and took 3rd place in speed. We had to take the photo from the right side to see the bite (which is actually from Blake). He bit into a piece of foam and we traced it to the wood.

Photo Finish - Gary Kranston

This car competed in my daughter's Indian Guide Pinewood Derby last year. Since my daughter is getting older and she likely won't do this many more times, I wanted to create a special keepsake for her. I used clear acetate, and applied a decal I created to look like a filmstrip with some special pictures of our camping adventures together. Also, I used some small watch batteries to power a flashing yellow LED light at the front of the car and two white LED lights beneath the filmstrip. Not only was the car fun to look at, we raced it with outlaw wheels and won!

Flex Car - Tom Bybee


I compete in the open class in our pack which was designed mainly for adults and has very few restrictions. However, there is still a restriction of no external springs. Since we use an older wooden track that is pretty rough in places, cars lose a lot of energy because the entire weight of the car has to go over every bump. This year I tried a flex design. By doing some clever cutting and a lot of sanding, the car has four-wheel independent suspension -- each wheel can flex and move more than 1/4 inch. With this design I was able to move the weight further back on the car (the wide area at the back is filled with lead) without fear that it would "pop a wheelie". It also absorbed track bumps without losing much energy. Although from the picture it may look fragile, it is actually quite strong and won every race by well over a car length.

From Pinewood Derby Times Volume 8, Issue 6

Subscribe to this Free Pinewood Derby E-newsletter

(C)2014, Maximum Velocity, Inc. All rights reserved

Maximum Velocity Pinewood Derby Car Plans and Supplies

Thursday, September 11, 2014

PINEWOOD DERBY MEMORY
Highest and Longest

We had heard about the upcoming World's highest and longest Pinewood Derby track event, so we decided to go. We picked out some cars from my son Patrick's, collection, and I took him and his friend downtown to the museum. Patrick chose the car that he made as a Tiger Cub, an Indy-style racer. His friend, Bryce, picked out a car loosely based on the Dragonfire car plans that were part of a design booklet we had purchased. I got greedy and took two cars, a car based on a 60's Indy Watson Roadster that I made for myself when Patrick was a Cub Scout (so I could keep my hands off of his car), and a vintage "skinny wheel" car made in the 1960's.

We had seen the track on TV, so we knew it was going to be high and long, but it was even more impressive in person. There were lots of friendly volunteers helping out with the racing. We quickly got our cars inspected, and were ready to roll.

The aluminum track was four lanes suspended from the ceiling. The starting gate was perched over the second floor railing, and the track made a graceful arch down to the main floor and the finish line. The scoring results were recorded and displayed on a big screen TV near the finish line. Each car was allowed three timed runs. The fastest ten cars would be eligible to compete for one of the top five trophies that were being awarded for the event.

All of our cars ran nicely, but not near the top ten times. The top times were in the 4.5 second range; the best any of ours did was 4.6 seconds. Still, it was awesome to see the cars from below, rocketing down two stories of Pinewood Derby Race track right down to the finish line. You don't always have to win to have a good time.

I was surprised to see the vintage Pinewood Derby car, made in the 1960's, holding its own racing against the newer models. It brought back fond memories of my son's Cub Scout enjoyment of the Pinewood Derby. I found this reflected in the faces of all the kids who were having the time of their life racing their cars on this day.

In addition to the kids, there were several "Old Timers", like me, who brought their boyhood creations down for one more taste of Pinewood glory.

Two kids that we met that day stood out the most. One boy was there with his Mom. The boy's dad was out of town, so Mom got Dad's old Pinewood car for the young man to run. It was probably a seventies car. The builder used the wider 70's tires for the back and a couple of older skinny wheels in the front. It gave the car a very distinctive look. The son was having the time of his life "driving" daddy's car.

The other youngster who caught my attention was probably 6 or 7 years old. His car was one that he had made "All by himself"... with a little help from Mom. The car, was nicely painted silver, and had a Lego driver in the cockpit, with horns on it's helmet, and he had found a matching sticker to decorate the back. It was really neat to see the joy and pride on the face of that little boy -- it brought back lots of fond memories of Pinewood Derbies past.

All in all, we had a really great day taking part in a bit of Pinewood Derby History. I heard from one of the volunteers that they may make this into a yearly event. I sure hope so.

Bob & Patrick Henderson

From Pinewood Derby Times Volume 8, Issue 5

Subscribe to this Free Pinewood Derby E-newsletter

(C)2014, Maximum Velocity, Inc. All rights reserved

Maximum Velocity Pinewood Derby Car Plans and Supplies

Wednesday, September 03, 2014

PINEWOOD DERBY CAR SHOWCASE

To the Rescue - Chris & Kaycie Tufaro

This is the car my daughter, Kaycie (age 10), and I built for her 2008 Powder Puff Derby. It is a basic wedge design with a few special add-ons. In front is what is left of a car after a large "boulder" had fallen on it. Behind are emergency vehicles coming "to the rescue". The "Falling Rocks" sign was another creative touch. Although she did not win a ribbon for any of the "best of themes" (most colorful, favorite food, sporty, girl scout values, etc.) the car ran fast and we had a blast making it.

Two-wheeler - Bob Weaver


After seeing my two-wheeled car, Bob dropped by Maximum Velocity to show me his version. Modeled after a car that was entered at his pack's race many years ago, it runs on the right-front, and left-rear wheels; the other wheels are off the ground. Unlike my car which is center-weighted, Bob's car is rear weighted (balance point at 1-3/4 inch in front of the rear axle) by offsetting an underbody lead plate to the left. It is possible that this design could be made faster by using tungsten plates and shifting them further back. Nevertheless, the car is very fast; it has taken first in several races.

From Pinewood Derby Times Volume 8, Issue 5

Subscribe to this Free Pinewood Derby E-newsletter

(C)2014, Maximum Velocity, Inc. All rights reserved

Maximum Velocity Pinewood Derby Car Plans and Supplies