It was a testament to ingenuity and simplicity. A chassis with an upright coil (C), and a non-ferrous graphite rod (A) passing through it; a plate with pickup shoes (E); and an actuator reed (B) to deliver power to a drum (D). When powered, the magnet attracted the reed to it, which came down upon the drum, making it rotate a small amount. The act of the reed coming down, also forced the rod through the center of the magnet to come down on the connection of the pickup plate that broke the circuit, thus releasing the reed to return to an upward position. This allowed the rod to rise, making the circuit complete again, which started the process all over again.

These originally came with AC power packs, but run on DC just as well. They also only run forward. The first incarnation came in four body styles, under the Playcraft Highways name. A year later, Aurora bought the model, and came out with many more styles of bodies.

Never meant to be any more than an adjunct to model railroading, there seemed to be little thought given to performance. They had some great body styles, and clever ideas. Look at the track choices that included intersections, junctions, turnoffs, and more. The semi, which came with a trailer mechanism that made the trailer wheels track opposite the way the cab was turning (bottom, right). Very clever. And the attention to detail with a driver who wore a hat and a mustache.

But the chassis were prone to failure. The coil seemed to break, often, possibly because of heat. There was little else to do but oil the axel races, for purposes of tuning. We decided to see if maybe we could quantify that a little more.

First, it is imperative that silicone tires replace the originals in the rear. Several people make these to fit the Vibe rims. Hiester, and Stinson, to name a couple. Next, install the pick up plate. With an eraser, thoroughly clean the two points where it has electrical contact with the chassis. Then adjust the shoe height to just below the tires, and even flatten them out a little.

After sliding the rod through the coil, install the reed. Make the drive piece as parallel to the drum as possible (Since it screws on in 2 places, there is enough play that you can wiggle it into the best position, side to side, and backwards and forwards). Now you need to adjust the contact with the drum. There are two issues. First, the angle at which it addresses the drum, and the angle of the drive piece to the top plate (they form a near 90 degree angle). Near as my tests reveal, it is best that the top plate be more than 90 degrees to the bulkhead just behind the coil (the plate seems to have a bend near the rear), and the drive piece make as little contact with the drum as possible. The rear wheels will spin quite freely, and have no contact with the reed until the reed is depressed a bit.

It is possible to mount the Hot Rod rims to Vibrators, because they have the 3 axle holes, like the Thunderjet. This could certainly allow for added traction and top end, but with the caveat that silicones are still the best way to go. One other nice feature of the design is that the pickup shoe plate and guide pin mount with a single screw, so the chassis can be run without a body. Screw holes are similar to Thunderjets, so both chassis and bodies are interchangeable with most bodies.

Visit the HO World Museum for more shots of Vibrators. Don't hesitate to give these a try if you run across the parts. They are very rare, but there are still a few guys out there who have some. Happy Model Motoring!

Note: If any of you need the rods, Jim Walters has some that are made out of delrin. These work very well, and are not as fragile as the original graphite ones. Email him if interested.