Skate Wheel Dollies: Understanding and Operating
Skateboard wheel dollies make it possible for a dolly to effortlessly and silently move on track. Some dollies are exclusively made with skateboard wheels and can only be used on track, while others can be adapted to work on track by being placed in trays that have skateboard wheels. The skateboard wheel design evolved from early dollies that used ball bearings.
Today, we see dolly shots in almost every professional production, but back in the 1960s, it was very difficult to use one due to the fact that they were so noisy. The ball bearing wheels helped contain the problem, but it was the skateboard wheel that really made it possible to glide on track without ruining the sound during a take.
How It Works
The skateboard wheel is usually made out of polyurethane and is designed to move easily over cracks in pavement. Like most things, it was hijacked by some very inventive people in the film industry to suit their needs. Two wheels form at a 90 degree angle to move on the track without sliding off. In order for a dolly to work functionally on track, there needs to be two skateboard wheels positioned like this on four corners so that the weight is equally distributed.
JL Fisher and Chapman, the two biggest dolly companies in the industry, make skateboard trays that employ eight wheels in each corner. There are two wheel trays where the front and back of the dolly rests. Fisher updated the design a few years ago to allow the trays to swivel so that they can be used on curve track. These trays have a red dot on one side and a blue dot on the other. Both colors need to be on the same side of the track in order for the two trays to swivel properly.
Making Your Own
If you can't afford or don't want to rent a skateboard wheel dolly system, you can easily make your own with some speed rail, eight speed rail 90 degree couplers, skateboard wheels, a drill, bolts, nuts and washers. You will also need sand bags and plywood to serve as a platform.
Cut the speed rail into the desired length for the track. Then, cut two pieces slightly larger than the desired width. Join these pieces together with four of the ninety degree couplers. You will need a 3/16 Allen wrench to tighten it. This is your track. Make sure that the length sides are placed on the bottom so that the speed rail won't bend.
Cut the remaining speed rail to the desired platform lengths. On the pieces that will be parallel to the length of the track, you will drill two holes that are 90 degrees apart from each other on each corner. Connect the platform together with the other four couplers. The pieces with the holes should be on the bottom. Add the skateboard wheels to the speed rail. Then, add the plywood. You now have a skateboard wheel dolly.