The rocker cover race at the WA DoVW was great fun. This year we had a small number of entrants (about 10) and so it was allowed to be informal, with a race at about 1.30 p.m.
Unfortunately I had to change the track at the last minute. I built a single 2.4 metre ramp with 7 metres of run on track, but no test racer ever made it to the end, because of the slowing effect of hitting the side walls.
I rebuilt it to have 4.8 metres of ramp that then ended on the grass, so the first to the end of the ramp was a winner.
If we had had a good smooth floor or surface to run the racers onto, it could have then been the first to a finish line a few metres further on that won. There is no such surface at G O Edwards Reserve, so we had to end each race at the end of the ramp.
Here are some observations of mine.
Short wheel base is not a good idea. If mine, the white one with skateboard trucks, hit the side walls it turned sideways and stopped. A blue and white one with big disc wheels hade a very short wheel base and it stooped on the side walls every time.
As wheels CDs are not strong enough. The one with CDs for wheels won its heat by breaking its front wheels on the side walls and tumbling the rest of the way. Side protection rails might solve that problem. Hard drives would make much stronger wheels and they have a good bearing in the centre.
Low centre of gravity helps.
The one with very small wheels did well and was only just beaten.
Heavy helps to overcome starting rolling resistance, which runs counter to what we all learned at school about Galileo, and the dropping of different weights from the Leaning Tower of Pisa, which showed that the weight of an object has no bearing on its rate of falling and wind resistance does.
Anything poking outside the line of the side of the wheels would catch on the side wall and either slow it down or turn it sideways. Wheel nuts and spark plug decoration grabbed the side walls.
Keep the sides smooth to slide on the side walls rather than catch on them. A wire side guard may help.
Skateboard trucks are O. K., but rollerblade wheels are better.
Next year we hope to have many more entries and we may then run elimination heats and a Grand Final race.
Thank you to all of the entrants. It was good to see your efforts and ingenuity. Some of the decoration was excellent.
Thank you also to Chris of Idlewild Off Road for sponsoring the rocker cover race and for providing the cash prizes.
See you there next year.
shaihulud Custom Title Time!
1,448 posts · joined Nov 2005 ·
