Dennis' LEGO Pinewood Derby race car with the full-size all-LEGO prototype (we used as a reference while cutting and carving) and his original 3-1/2 inch inspiration. It scaled up perfectly at 200% to make a regulation 7-inch pine car.
The original block of pine wood from the kit, marked up with Dennis' design.
It was simple enough that we built a virtual model in MLCad mlcad.lm-software.com/e_default.htm and then printed a side and top view 7" long use as a template to mark the intended cuts.
The block was then shaped with a hobby hacksaw, Dremel tool, and LOTS of sandpaper.
Dennis using hobby hacksaw to cut LEGO "studs" out of 3/8" dowel.
We drilled 24 shallow holes with a 3/8" Forstner bit to make flat-bottomed holes then secured the pegs with carpenter's glue.
When the glue was dry a quick run with a palm sheet sander over the tops of the studs brought them all to a uniform height.
The car mostly assembled, ready for sanding and priming. The cockpit was hollowed out using a large Forstner bit, then cleaned up with a Dremel tool.
We used 3/8" thickness balsa wood to widen the sides of the car. In retrospect, we wished we has used balsa wood for the rear 2x2 slope and spoiler because we had hoped to include a driver.
Dennis has a Playmobil dude he was going to repaint with a yellow smiley face to look like a large LEGO minifig. Our final race weight was 140 grams (4.938 ounces) with no driver or added lead weights.
Dennis' design won the Pack 561 "Most Creative" award as voted on by the other scouts. Webelos-2 scouts did get to race but weren't eligible to win any speed awards.
Dennis won overall pack Pinewood Derby champion for fastest time in his Tiger and Webelos-1 years of Cub Scouts.
Dennis proudly displaying his finished creation. (note smudge of graphite on side of nose) We loaded up those plastic wheels with a whole bunch of the powdered lubricant to reduce friction. Proper axle and wheel preparation also make a huge difference in performance.
This was made from a new Official Grand Prix Pinewood Derby Kit and conforms to all car specs:
Our council also said height cannot exceed 3 1/2 " (3.0") plus no part of wheels may extend past front or rear of car; front end clearance can't be more than 5/8".
This project does not have any discussions yet.