Відео

I tried printing the outer wheel holder and the tolerance was too tight. Ended up scratching up one wheel pretty significantly :( Any tips on how to loosen the tolerances up on the outer wheel holder? I am trying to make the balancer today and will report back my findings

That would be against the Pinewood Derby rules

We just freehand polish the wheels using a nail file or the Tamiya file Chuck the wheel up and mount it I to the drill that's clamped to a table, power up the drill and use the nail file to touch up the outside circumference and remove sharp edges.

Thanks Grandma Lola!

Thanks for the comment! My fixture drills the holes at a 2 degree camber, 90 degrees to the body. I use that for both of the rear wheels. For the front wheel I also drill one at 2 deg camber, and the raised one with zero degree camber. To steer the car, we are using guide wheels that engage the sides of the pinewood derby track. I found that easier than setting up for rail riding.

Thanks for watching!

Thanks Greg!

Not yet. I do belong to SnoCo Maker Space - and can teach classes there. They have oodles of 3D printers and laser cutters, and I know they want to do more kid outreach. I am in the process of putting together program for said classes - but it'll be a few months out. I also would want to make sure that the home built laser cutters have proper safety cutoffs and such enabled instead of relying on the "Dang - don't look into laser with remaining eye" warning label...

@@AMakerDad keep me posted. My friends’ kids may be interested.

Our pack (pack427.org/about/) is co-ed and welcomes boys and girls from K-5! The Wolf girls had some fast racers this year. Also, being in an area where so much of the workforce is in tech (Amazon, Meta, Microsoft, Google) it's not unusual to see 3D printed trinkets in my youngest's birthday gift bag or candy flinging robots for halloween during COVID. It's really inspiring to see so many young kids get into science and engineering early.

Nothing is preventing Girl Scouts from doing this beyond no one taking charge and doing it! I personally coordinate and run our Girl Scouts local service unit derby which includes all Girl Scout Troops within about a 7 mile radius, making it a far bigger event than the local individual Cub Scout Packs derbies. If your service unit can't afford the cost of the track, talk to the local Cub Scout packs, you will likely be able to find one that will lend you their track for a nominal fee (or even free) or in many cases they might even offer to run it for you or help you run it. You might even be able to coordinate with a local Cub Scout pack to run your Girl Scout derby after they run theirs that way it's all set up and ready to go, then you can help them tear it down and put it away.

Glad you enjoyed it! :-)

That's interesting! I am not a fluid mechanics guy at all... but from a physics standpoint, running the wedge in reverse, you'd have a hard time shifting the center of mass that far back on the car. In fact, another UA-camr found out by experimentation that to set the center of mass about 20-25mm from the rear axle, your car on average can't be more than 10mm thick. That's why almost all winning cars are basically low to the ground skateboards with weight on the back. By far, the biggest contributor to winning Pinewood Derby - aside from axle and wheel prep, seems to be the placement of the center of mass. I plan on doing a follow up video where I test each of the variables with the scientific method.