Mid America Pinewood Derby - 2018

They will be on the site before the end of the day

xanthrum Greg, what size box do you recommend sending the car/s in? I know you recommend sending a larger box , would the square (large) USPS flat rate box be large enough?

OK fellas,

I am looking at the MA Open Adult Oil Class...

Here are the rules:


. - Body Specifications
Width – not to exceed 2 ¾ inches (7cm)
Length – not to exceed 7 inches (17.8cm)
Height – must have clearance under Finishing Gate – not to exceed 6 ½ inches
Weight – not to exceed 5.0 ounces – 143.4 grams measured on Official Race Scale
Overweight cars may be reduced to 5.0 ounces (143.4grams) or below before they can officially be entered, at the Race Day Check in.
Center Rail Clearance – Cars must clear the center rail which is 1 5/8 inches wide by ¼ inch tall along the entire length of the car.
Wheelbase –Can be extended. Standard wheelbase is 4 3/8 inches from center of front axle to center of back axle. Any wheelbase can be used. Wheels must be directly across from one another.
Axle holes may be drilled into body of car as long as the specs are met.
The main body structure must be made of pinewood
Body design may be enhanced by adding other stable materials such as plastic, metal or details. All additions must be firmly attached and conform to size specifications. No loose materials will be allowed on the cars.
No part of the car’s body, wheels, or attachments can extend beyond the starting peg on the track what so ever. Additionally the wheels may not extend beyond the rear of the car or past the front of the car – the length is not to exceed 7 inches.



III. – Prohibited Items that can NOT be used
Magnets, springs or suspension systems of any type.
Starting devices, finish line devices, propellants, or propulsion systems
Wet paint, or Sticky substances
Glass or excessively fragile parts
Electronic or lighting devices (if lights are on the car they must be turned off)
Bearings (except in Pro-Bearing Division)
No use of Guide Pins or such devices
Axles and wheels attached to any device that mechanically alters rotation or spin.
IV – Wheels
Only Official BSA Wheels are allowed (either new style & old style) all markings must be intact on inside and outside of wheel. You may use the Official BSA Colored wheels
Outer wheel surface may be sanded, shaved, lathed or polished to remove any imperfections, true roundness, remove mold castings and burrs, but must not be reshaped in any way to minimize tread contact or alter aerodynamics.
The fluting (small decorative dots) must be visible around the entire circumference.
The tread / contact surface must remain flat and parallel to the bore.
The width of the tread must not be less than 7.5mm
No removing or reducing the letters or spokes or drilling additional holes.
The following wheel modifications are NOT Allowed
No Rounding of the wheel treads – they must remain flat.
No Grooving, H-cutting, V-cutting, Crowing, Tapering or Dishing
No Altering the wheel profile
No Drilling sidewalls
No Filling of any wheel surface with any type of material
Officials will remove wheel(s) if lettering is not completely visable
Coning the hubs, truing the inside edge of the wheel, and removing the outer hub step down is allowed.
Wheel Bore treatment is allowed including polishing, sanding and / or tapping.
Wheel bores may not be filled and re-drilled
There must be at least four wheels on the car, however it is not required that all four wheels make contact with the track surface – one wheel may be lifted from the track surface.
Each wheel must be mounted on an axle, on the outside of the car, on the side of the car.
Wheels may not be greater than 10 degree of an angle from the body of the car
Each wheel must be attached by an axle - no guide pins allowed
Wheels must be installed directly across from one another
Wheels may NOT be reversed - wheels must be run in standard position
Non-Dominant / Lifted wheels must meet wheel specifications
V. – Axles
Nail type axles but not limited to those found in the Official BSA kit are to be used.
Modifications to the Axles are allowed that include straightening, sanding, polishing, canting, grooving, beveling & tapering of axle head as long as the Diameter of the Axle is not reduced the Diameter may not be less than .084 inches (2.13mm).
Axles can be mounted by drilling Axle holes or inserted into the slots on car.

VI – Lubrication
Graphite ONLY in Qualified Scout Division, Open Scout Graphite Division, Kids Graphite Division, and Adult Graphite Division
In Open Scout Oil Division, Kids Oil, Adult Oil and Pro Divisons - approved lubricants include (but are not limited to) Graphite, Teflon, Nyoil, Krytox
Officials will remove wheels if in question !!! Post Race Inspection will take place.

The question is what class professor?

That's the beauty of MA , you don't need to try and find a way around the rules to be competitive. MA allows builders to build a fast car by having a proper set of rules geared toward modern technologies and build techniques.

The 1.4 wheels should be perfect as long as they're stiff enough.