Thinking outside the starter box

Radio Control Car Action, Dec 2002 by Bess, Stephen

Starter boxes are among the most underrated, under-appreciated RC accessories. A pull-start mechanism makes life easier for the Writ crowd, but what do all the racers with non-pull-start engines do? Most use a starter box; this holds a spinning starting wheel and bumps it precisely against a model's flywheel. When property set up, a starter box can make engine starting a 2-second job. This month, I explain how to set up and use your starter box so that you'll be able to bump-start your engine easily.

STARTER-BOX SETUP TIPS

POWER CHOICE. Properly wiring your battery is vital to using a starter box. Your starter box probably has one, 12V get-cell or two, 6-cell packs. Both setups do a great job, but the heavier 12V gelcells last longer but have lower voltage and cranking power while the opposite is true of 6-cells. Regardless of your power source, here's what to took for when you first wire your starter box.

Twelve-volt power. A 12V battery is large and must be secured solidly to the starter-box frame. If it isn't absolutely secure, it will move around, and as wires are frayed and pulled, you run the risk that the positive and negative terminals will touch the same piece of metal and will short the battery; this can be dangerous. Use heavy-duty zip-ties to ensure that the battery is firmly secured (if your starter box's instruction manual doesn't direct you otherwise). Most 12V battery leads can be crimped onto the battery terminals; take the time to secure these leads property by squeezing the crimped part with needle-nose pliers (don't touch any other metal parts!).

Stick-pack-power. I've yet to see a stick-pack-powered starter box that didn't come with straps to secure a pair of packs. If your box is the exception to this, tape the two packs together and secure them in the box with zip-ties. If you have to, drill holes in the starter-box body for the ties to pass through.

DIRECTION OF ROTATION. In operation, an RC engine's crankshaft spins counterclockwise (viewed from the front of the engine); this means the starterbox wheel must turn clockwise (viewed in the same manner) to spin the flywheel (and, with it, the crankshaft) in the proper direction. If the starter wheel turns in the wrong direction, the engine will turn over and sound as if it wants to start, but it won't fire. Or you may actually be able to get the engine running backwards, but it will quit as soon as you apply throttle. Either scenario leads to misdirected troubleshooting efforts, so always check and recheck the rotation of the starterbox wheel. If it isn't turning in the direction you need it to, you should either reverse the polarity of the motor by swapping the positions of the positive and negative motor wires, or simply turn the vehicle around 18o degrees in relation to the starter box.

GUIDE SETUP. Starter boxes have some type of plastic chassis guides that you attach to the box lid, but many of us never take the time to use the guides, and when we do, we often fail to set them up properly. It takes only io minutes to set up the chassis guides, and they'll save you hours at the track.

Start by putting your chassis on the box lid and aligning the chassis' flywheel opening with the starter wheel. This will be easier if you first remove the vehicle's body so that you can see straight through to the flywheel opening from above. Having centered the flywheel over the starter wheel, note where the chassis sits on the box lid. Next, use a permanent-ink pen to mark the chassis perimeter on the starter-box top. Using the pen marks as reference points, install the guides on the box lid using the supplied fasteners. If you've positioned the guides accurately on your marks, you should now be able to drop your vehicle onto the box and have the starting wheel property aligned with the flywheel.

SWITCH HEIGHT. All starter boxes use a pressure-sensitive switch to automatically power the starter motor when the vehicle is pressed against the box's lid or starter pedal. The amount of lid or pedal travel (usually called "switch height") required to start the motor is adjustable, and it's important to proper starter-box operation. A properly set up starter box will power the starter motor well before the flywheel touches the starter wheel: this extra spin-up time allows the starter wheel to reach maximum momentum before the flywheel touches it.

Switch height is usually controlled by turning large screws that adjust the starter box's spring-loaded lid. Adjust your starter-box switch so that it spins the starter wheel when the vehicle's chassis is still well above the wheel but isn't so sensitive that the starter motor begins to spin as soon as the chassis is placed on the box.

NEW FOR NITRO

OFNA Multibox

OFNA's new Multibox sports a powerful 750 starter motor, it accepts 12V gel-cells or stick packs, and it has three starterwheel position to allow you to start virtually any engine. Its brushed-stainless-steel case looks trick, and you can buy the box unassembled or in RTR form.