Presentation on theme: "Building A Better Pinewood Derby Car Making It Fun for All (It Is No Fun To Be Embarrassed)"— Presentation transcript:
Building A Better Pinewood Derby Car Making It Fun for All (It Is No Fun To Be Embarrassed)
Official BSA Pinewood Derby Kit and Parts
Fast Cars Have A Thin Shape Heavier Cars Go Faster Long Wheelbase Cars Go Faster Rear Weighted Cars Go Faster Three Wheelers Go Faster Well Lubricated Cars Go Faster Friction Is the Enemy of Speed Isaac Newton Was a Wise Man
Tools & Materials Needed
Official Pinewood Derby Kitbondo bandsawgraphite drill or drill presssafety goggles and dust mask sandpaper - several gritssmall fine cut file cyanoacrylate gluegloves drill bits - 3/8” and #44wire cutters lead wirepipe cleaners - stiff ones small digital scalehoning paste or abrasive toothpaste
Creating Fast Axles Friction Is the Enemy of Speed
Stock Pinewood Derby Axles Have Problems
Chuck the Axles In a Drill and Use A Fine Cut File to Begin To Resolve the Problems
Use Sandpaper to Make the Axles Really Fast Wet Sand All Grits 600 and Finer
2400 grit 400 grit 8000 grit12000 grit + honing paste Finer Polishing Makes For Less Friction
Lube Axles With Graphite In Drill Chuck Well Lubricated Cars Go Faster
Fast Axles Created Friction is the Enemy of Speed
Fine Tuning Stock Pinewood Derby Wheels
Stock Pinewood Derby Wheels Have Problems
Wheel Chucked Up In Drill or Drill Press
Sand Sides Flat With 220, 400, then 600 grit sandpaper
Lube Outside of Wheels with Pencil or Powdered Graphite Well Lubricated Cars Go Faster
Use an Axle to Chuck Up Wheels for Sanding the Inside Edge of the Wheel
File and Sand the Inside of the Hub Round and Smooth - Sand to 600 grit
Use Honing Compound and Pipe Cleaners to Polish the Inside of the Hubs
Clean Hub with Pipe Cleaners, Soap, and water Lube Inside of Wheel Up With Graphite Well Lubricated Cars Go Faster
Tuned Wheels vs Raw Wheels Well Lubricated Cars Go Faster
In My Opinion - Don’t Allow lathe turned Wheels Cub Scouts Can’t Use a Lathe
Creating the Body (or Bodies, make 2 for each boy)
One Blank Contains Enough Wood for 2 Cars All That Is Needed is an Extra set of Wheels
Mark and Drill all Holes Before Shaping the Body
Drilling Template Fast Cars Have A Thin Shape Heavier Cars Go Faster Long Wheelbase Cars Go Faster Three Wheelers Go Faster Rear Weighted Cars Go Faster
Drill Axle Holes With a #44 Bit 5/8 inch from each end of the car and 1/8 inch from the bottom of the car. Drill hole for 1 of the front axles 3/16 inch from the bottom of the car. Drill the Holes for the rear axles all at once - through and through from one side.
Mark location for 3/8” holes for weights. Drill only to 1 5/8”depth so as not to drill completely through the body.
Best to drill a small pilot hole before drilling a hole a large as 3/8”.
Drill holes into the axle holes from the bottom of the car. This makes it easy to glue in axles without gluing the wheels to the axle.
Body Completely Drilled
Cut the body on the bandsaw. Create 2 bodies.
The first step in assembly - weigh the car and wheels. Add enough weight to bring the total weight to 4.8 oz. The finished car must weigh 5 oz or less.
Types of weights Heavier Cars Go Faster
Most convenient is 3/8” lead wire. Best source is RotoMetals through Amazon.com. Enough lead wire for 8 cars - $19.28 delivered
Car With 3 Inches of Lead Wire
Bring Car to 4.8 Ounces
Place weights into holes so that car balances at a point between 3/8” and 1.25” in front of rear axle Glue the weights in with cyanoacrylate glue - especially if they are loose weights such as lead shot Rear Weighted Cars Go Faster
Distribute weights so that the car will balance end to end at a point between 0.75 inch and 1.25 inches in front of the rear axle. Glue the weights in with cyanoacrylate glue.
Fill holes with bondo.
Sand and paint the car.
Apply graphite to body where wheels make contact. Friction Is the Enemy of Speed
Attach wheels. press them in using a 1/32” spacer placed between the wheel and the car.
Glue in axles through the holes in the bottom of the car with cyanoacrylate glue.
Ready for Weigh In Do not play with, or race the car before derby day USE THE SECOND CAR FOR THAT!!!
On Race Day - Bring Graphite Extra Weight Cyanoacrylate glue Needle Nose Pliers Extra Wheels and Axles Protection for the Car - Carrying box, etc
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