Dennis Wang Cubmaster Pack 199 Pinewood Derby Chair Pathfinder District
Introduction & Welcome Dennis Wang Cubmaster Pack 199 Pinewood Derby Chair Pathfinder District Pinewood Derby Enthusiast
Pinewood Derby Cars 2013 Wolf Scout - Batmobile
Pinewood Derby Cars 2013 Sibling PVZ Lego Race Car
Pinewood Derby Cars 2014 Bear Scout - Enderman
Pinewood Derby Cars 2014 Tiger Scout - Steve
What are we going to do today? We are not building cars today Good Sportsmanship Go over strategies for building a fast car Review of tools needed to build a car Going over basic building techniques
The Down and Derby Syndrome Who should build the car? Scout Dad Both
Sportmanship Cub Scout Motto? Know the rules of your race Pack and District races can and should have rules Follow the rules In every race, there will be one winner and then everyone else. At the end of it all, there will be one winner and then the rest of the pack.
Sportsmanship It s not about winning It s about having building something as a team: Akela and Scout. It s about watching that car race down the track It s about learning something new: Physics Craftsmanship Using tools Good sportsmanship Remember the Cub Scout Motto and the core value of Positive Attitude
Pinewood Derby It s about having fun!
Pinewood Derby Clinic Physics Clinic Pinewood Derby is really all about physics Energy Kinetic Energy (Motion) Potential Energy (Stored Energy) Batteries are stored energy Lifting a weight creates stored energy
Physics Clinic Energy Center of Mass/Balance Point Where do you want the Center of Mass of the car to be: front or back?
Physics Clinic Conservation of Energy Ideally, all the potential energy is converted into Kinetic Energy 10 Ideal Conservation of Energy 8 6 4 2 0 Potential Energy Kinetic Energy
Physics Clinic Friction What is friction? Friction Experiment: Kinetic Energy is motion Pretend to rub your hands together Now rub them together really fast How do your hands feel? What forms of energy did you convert motion into?
Physics Clinic In reality, some of the potential energy is converted into other forms of energy 10 Actual Conservation of Energy 8 6 4 2 0 Potential Energy Kinetic Energy Friction (Heat) Rotational Energy Sound
Physics Clinc Physics and the Pinewood Derby by Scott Acton Conducted many experiments and documented the impact they have on speed Published a DVD on his experiments
Physics Clinic # Parameter Car Length Advantage 1 Center of mass location 4.6 (36%) 2 Lightweight wheels 2.1 (16%) 3 Aerodynamic 1.4 (11%) 4 Polished nails 1.3 (10%) 5 Lift one wheel 1.1 (9%) 6 Graphite 0.9 (7%) 7 Other (long wheel base, car shape, wheel gap, etc.) 1.4 (11%)
Tools Safety First Hand Tools Power Tools Pinewood Derby Specific Tools
Tools: Safety Always supervise Scout while using tools Safety Goggles Hearing protection
Tools: Hand Tools Saw Coping saw Cross cut saw Hammer Pliers Clamps File Sandpaper
Tools: Power Saw Band saw Scroll saw Drill Sander Belt Rotary Rotary Tool Dremel
Tools: Speciality Weights Lead Tungston Other alternatives Digital Scale with accuracy in the hundredths place Graphite lubricant Axel Pliers Axel Guide Axel Press Hub Shaver Wheel Mandrel Axel Polishing Kit
Building The Car 1. Insert Axels into pinewood block 2. Polish Axels (Parameter #4: Polish Nails) 3. Come up with a design* 4. Cut out and shape the car 5. Paint the car 6. Weigh all parts to determine how much weight is needed to get you up to 5.0 oz. 7. Install the wheels 8. Weigh the car again to make sure it is at 5.0 oz 9. Align the car * 10. You car is now ready to race
Building The Car Step 3: Come up with a design Know your rules Max weight is 5.0 oz Dimensions (max 7 x 2 ¾ x 4 ½ ) Certain shapes may not be allowed Which end of the block is the front of the car vs the back of the car (Parameter #1: Center of Mass Location) Determine where weights will be added (Parameter #1: Center of Mass Location) Shape (Parameter #1: Center of Mass Location and Parameter #3: Aerodynamic) Draw the design on the template Cut out the template and attach it to the pinewood block
Building The Car Step 9: Align the car Not listed as a parameter, but it is very important Straight Rail rider
Race Day Be prepared to adjust the weight of your car when you check in. Your scale is probably not exactly the same as the official one. Have extra weights: weighted putty is good to have Bring a drill so you can quickly remove some weight from parts of the car Just drill out a few holes from the bottom
References You can buy books from the Scout Store All tools listed are available in the Scout Store References on the second to last page of the packet Template is available on the last page of the packet
Questions? cubmaster@pack199.nwsc.org