Additional Notes on BestTrack Electronic Finish Line Conversion
Our finish line sensor systems strongly
suggest that that you use
individual weights for
each line, rather than lacing the line back and forth, as is sometimes suggested
for the
Space Derby tracks.
The tighter the line, the better
the rocket will fly. No matter
how smooth the bearing, it will
still have some friction. The cumulative friction from lacing makes it
hard to keep tension
in all lanes equal, whereas
individually weighted lines promotes lane fairness. Plus, if a
single line should
happen to break, it won't bring down the entire track.
You can use eyehooks, available at Home Depot to make four inexpensive weights.
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Trap a large washer between two nuts on the eyehook |
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Fill a coffee can with cement and embed the hook. A 12 ounce coffee can makes a 5 pound weight, which produces twice the tension as the suggested 5 pound iron weights that were shared between two lanes. Make your lines long enough so the weight is near the floor. In case the line breaks, it won't have far to fall.
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 The BestTrack eyehooks are open, which makes it very easy to use this simple secure knot at each end of the line. |
Rather than buy a pair of olympic 10 pound weights, use cement again and save
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The Handle: $1.54 at Home Depot. Take an 8" bolt, with nut. It can be 5/16 or 3/8"
Add a pair of 1/4"-20, 5" long eyebolts, each of which has a washer trapped between a pair of nuts.
Make a platform 3 and 1/2" high, above a level surface.Cover with plastic, and set a cement block on top. We used an 8" block, since it was all we had lying around.
Fill the block with cement, move the BestTrack into place, and suspend the handle assembly into the cavities. Take care to get everything centered and symmetrical.
The 8" block made a 60 pound weight, which was frankly, too heavy. In retrospect, a 4" or 6" block may be have been more appropriate.
But alas, the design had already been cast in concrete. (bidda boom!) |
The electronic BestTrack finish line, with cement weighting |
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See additional Notes regarding the tubes needed on each line.
Contact: New Directions, 900 Echols Street SE, Vienna, VA 22180 | 703-319-0840 | Email
