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John Thawley
05-03-2011, 10:14 PM
Marlon is competing in the Pinewood Derby at Cub Scouts this year. He swept his pack competition undefeated including the Bears winner, Overall winner and Best In Show (looks, prep etc.)

The rules for the Pack's race were pretty vague and so we went with an extended wheel base car. Now that he has qualified for the District Championships, the rules are clearly spelled out and the wheel base must be maintained from the original Pinewood Derby kit. So... we prepared a new car ... and of course incorporated all the things we learned from the first car. This one rocks... and I've got a hunch will be a formidable competitor.

The car is a three wheeler with the left front mounted 1/16" off the track. The block was lightened to require 3 .oz of tungsten. One ounce mounted in the bottom rear of the car and two ounces at the rear axle. Axles are trued with beveled heads and polished. Wheels are sanded round, polished and mold matched. Wheel "wells" were left unpainted and polished with graphite. Hubs were graphite packed and wheels were run-in (spun on axles with Dremel) reapplying graphite every few minutes. (in theory, the car has about 100 runs on it). Front end is channeled for instant gate clearance (quick start) and the car weighs in a 4.990. Bottom is finished with aluminum finish adhesive film.

:)

Steve Stein
05-04-2011, 11:00 PM
Pretty cool looking. How much downforce does that wing put down? Any wind tunnel testing? :)

John Thawley
05-05-2011, 12:09 AM
Pretty cool looking. How much downforce does that wing put down? Any wind tunnel testing? :)

The wing actually is "folded" down prior to staging... it's memory is good for a quick downhill run. My kid had a hard time understanding why you don't want a spoiler on a gravity powered car... so this was his chief engineer's compromise. LOL

Scott Lepage
05-05-2011, 07:17 PM
Sweet car. It inspired me to go out to the barn and drag out my historic pinewood car. It dates back to the mid 1970's.:D http://s3.amazonaws.com/data.tumblr.com/tumblr_lkqwkxIMM31qbbs8yo1_1280.jpg?AWSAccessKeyId =AKIAJ6IHWSU3BX3X7X3Q&Expires=1304723711&Signature=%2BlVr39M%2FdJZ3OmjZrRjxA0glwyA%3D

John Thawley
05-05-2011, 07:28 PM
Driver appears not to pleased with the car setup!

Steve Stein
05-06-2011, 09:44 PM
Driver appears not to pleased with the car setup!

You know the talent. They never are pleased with the setup. He taking lessons in attitude from Danika?

Daniel Buck
05-22-2011, 02:07 PM
nice :-D I'll have to dig out my old derby car, I made mine look like an old 30's hotrod, haha!