Pinewood Derby Outer Tread
Remember those flaws that we pointed out in the previous sections, well the outer tread is no different. What we want is a uniformed outer tread so that we can have the true round rotation. This can be achieved in various ways. The direction in which you choose will be determined by your LOCAL PACK RULES. If you want to get really creative, you can profile your wheels using cutting tools to leave just a small amount of wheel surface to reduce nearly all friction. CHECK YOUR RULES!
Pro Tip – Camber your wheels using bent axles or drilled axle holes. 2.5-3 degrees will make a world of difference. This allows for minimal wheel to track friction.
Some packs only allow light sanding. Rules will sate something in effect wheels must be greater than 1.180″ in outer diameter. Or no removal of material of any kind is allowed. For this method there is really only one way to do this. The wheel needs to be inserted into some sort of holding tool. Then that tool needs to be spun, and then you need to go through various stages of WET sanding. We suggest 400-2000. Below is a YouTube video that explains thing very well. Great job with the video. Remember this is for rules that only allow wet sanding. You can also do this to machined wheels for a smoother finish. The tool used for this is the Derby Worx Pro Mandrel
If you rules allow removal of material
If you rules sate something in effect wheels must be greater than 1.170″ or give another number less than 1.180″ then you will be pretty safe with manual removal of material. There are 2 methods to doing this. One is with a lathe, the other is with the Derby Worx Pro Wheel Shaver. If you have a lathe, you are probably not reading this so we really will not address that issue. All Derby Dust Wheels are turned with CNC Lathes. Removal of material is the ultimate goal of all pinewood derby speed wheels. A lighter wheel will always be a faster wheel. With the removal of material resulting in a outer diameter of 1.172ish will yield about .2 grams of weight removal (overall weight 2.4ish per wheel). Doesn’t sound like much, but every bit counts. Give a racer 1.2 gram wheel when he ordered 1 gram wheels and see what reaction you get. Ultimately pinewood derby wheels with no internal lettering can not get lighter than 1 gram in weight.
Pinewood Derby Wheel Inspection Gauge Go / No-Go
Our Wheel Go/No-go gauge will help you improve your race by providing a consistent and quick way to inspect pinewood derby wheels while the wheels are mounted on the car. Inspection is a breeze once you understand how to use this tool and there will be no arguing about caliper bias.
Please do not try and force the wheel between the tongs. Simply try to pass the gauge through the wheel from the bottom up. If the wheel does not pass through then the wheel PASSES inspection. If the wheel is able to pass through the tongs, then it fails that measurement.
Weight reduced wheels are very pliable and thus calipers will make them fail every time. Bring one of these guides on race day to ensure you do not get D/Q because of measuring bias. If a car is built with wheel wells (fenders) , the OD gauges cannot be used (of course a digital caliper cannot be used in this situation either). Be prepared.
- No Wheel Modification Allowed – If the wheels may not be sanded or modified in any way, then use the 1.180 OD gauge and the .360 width gauge.
- Wheel Modification Allowed – If the wheels may be sanded or lathed, then use the 1.170 OD gauge and the .320 width gauge unless otherwise stated by your packs rules.