Derby Update

No updated pics yet, but the boy has started painting his, mine has 3 coats of paint and the lass’ is almost ready to paint. Once again, I underestimated the weighting game.

Cutting out the car shapes and polishing the wheel axles are piddling compared to weighting the car. You’d think that hitting something near a 5 ounce mark would not be so difficult. I mean, really, 5 ounces isn’t that much. How much weight can it possibly take? So far, the answer is “More than you expect, even after a test weighing.” It’s compounded by the difficulty in knowing how much weight is removed from the car after drilling out the bore holes for the weight to go into. Sure, there’s a net gain once the weight is in their, but it’s not the same as putting the weight on the scale along with an untapped car. I think a rough gauge is that you’ll need an extra 3/4 of an ounce of weight. But that varies with the car shape as well.

Even drilling out the car isn’t straight forward, since the amount of drilling is determined by the amount of weight needed. If the initial estimate is off, then it becomes a game of figuring out where the heck else the darn thing can be drilled.

Oh, and don’t forget that the car needs to be balanced so that it won’t pop-a-wheely out of the starting gate. Guaranteed loser then.

At this stage, the boy’s car has posed the fewest problems. Mine needs more weight, but I have no room left on the top, so I intend to epoxy some weight onto it at the race.

The lass’ has been very difficult. The car itself, prior to drilling it out, weighed less than 2 ounces (that included the wheels and axles). By the time I was done drilling it out so I could fill it in with the weight, there’s probably less than an ounce of wood left. When I added the weights, I also filled them with glue to gain as much extra weight as possible. Additionally, her car design puts so much weight towards the rear that I’m afraid it will want to do a wheely out of the starting gate. I put a some weight in the front, attempting to minimize the possibility, but I don’t know if it will work. The big bummer here is she couldn’t help a lot because the setup for the drilling was tedious and beyond her current capabilities. Though, in retrospect, I probably should have had her watch and explained what I was doing. Live and learn, as they say.

The kids took turns polishing their axles on the drill press. That included putting the nails into the chuck and then filing them as well as polishing them with wet/dry sandpaper. Additionally, the boy drilled out the bore holes for his car’s weight, used the hacksaw to cut the weights to fit, helped seal up the filled holes and did the painting. A big step in the right direction from last year, where he wasn’t nearly as involved in the actual construction.

All in all, a decent weekend of derby work.