How to use the Hub Tool to improve Your Car's Performance
Note: The pinewood derby wheels available for the last few years have the hubs pre-coned so this procedure is no longer needed.
This tool has three important Pinewood Derby car wheel preparation uses:
Hub Squaring - Squares the wheel hub to the wheel bore so that the wheel will will spin smoothly.
Hub Coning - Reduces friction by reducing the contact area between the inside wheel hub and the car body.
Bore Reaming - Makes sure that the axles fit properly in your wheels.
This Tool has a square end to improve wheel hub accuracy and a coned end to reduce hub friction. Check local rules before coning wheel hubs. This tool also reams undersize wheel bores.
Molded Pinewood Derby car wheel hubs can vary in size by as much as .01". This tool will allow you to ream the wheel hubs all to the same size or help in selecting 4 wheels with similar hubs. This is one of the most important steps in alignment because the car will sit square on the track when all wheels have the same radius.
Test fit each wheel by sliding it onto the tool pin. If the wheel won't slide on , the wheel bore is too small. Use steady hand pressure and a twisting motion to work the wheel on to the tool. Remove the wheel and repeat 3 times.
This tool can also be used for coning the wheel hubs. All Pinewood Derby cars will benefit from coning the in-board hub for a reduction in body to hub friction. This tool makes an even, polished cone that reduces body contact by 95% and can even be used to polish in graphite by adding a small amoujnt in the dished end after coning for even more friction reduction.
Dip the coarse grit sandpaper (included) in a cup of water. Remove the protective cap from the square end of the tool, pierce the sandpaper (grit facing outwards) and slide the sandpaper until it contacts the body of the tool. To minimize the risk of a hand injury, leave the protective cap on the coned end of the tool.
Place a wheel onto the square end of the tool, hub side first. With one hand hold the tool and the sandpaper. With the other hand, press the wheel against the sandpaper. Rotate the wheel back and forth for about 10 seconds.
Repeat for the other wheels. Use a new area of the sandpaper for each wheel. If the hubs will not be coned, repeat with the fine-grit sandpaper.
To cone the wheel hubs, perform the above steps using the coned end of the tool and the coarse-grit sandpaper then repeat with the fine-grit sandpaper.