Skateboard Dolly Project: Part 1 (Concept)

| | Geoff's Blog

One of the most important aspects of professional looking film is camera movement. Of course, dollies, cranes, jibs and steadicams are some of the most expensive pieces of equipment on the set, not only because they are precision machines but also due to their sheer size. On the DIY side of filmmaking, there are a million novel ideas about achieving camera moves (basically mount the camera to something that moves and you have a new mount!), but many aren't exactly capable of smooth professional moves or the durability that is needed on set. I know, I've built a few failures myself. Lately I've been trying to aim for something that is ideally the best of both worlds but is at least somewhere between the two.

We have a scratch-built 4-way steering doorway dolly already and it works wonderfully. I'll post some of the details of that build later. While it has an amazing turning radius and is very durable, it is also very heavy and not super smooth (although that depends on where you're shooting). So to beef up our dolly collection for some upcoming projects I'm building something new. Well something tried and true actually; a mainstay of indie filmmakers everywhere, the skateboard dolly.

Skateboard Dolly ExampleSkateboard dollies are so called because they use skateboard wheels. They can be as simple as a dozen-plus skateboard wheels and a sheet of plywood (and maybe a broom handle if you want a push bar. They have many advantages too. The skateboard wheels have built-in bearings making them easy to work with and since they are available everywhere skateboards are sold they are easily replaceable and fairly cheap. Skateboard dollies are also pretty much require track of some sort. So unless you have access to track or want to rent (if you can buy real dolly track, then buy a dolly too) a skateboard dolly maybe useless for you. Track, or lack there of, is the very reason we build a doorway dolly first. 

Track may be an issue but there is more than one solution. Film track is stainless-steel tubing 24.5" apart on center. It usually collapses like a parallelogram for transport, has a flat base for shimming and leveling and interlocks with the next track section. Curved pieces are available too. And it's expensive. For our use, however, track can be any length of rigid, smooth, parallel material. We considered PVC tubing or even EMT Conduit. The PVC would be too flexible in my opinion (although other's use for their dollies) and conduit is a little more expensive than I'm willing to go. And you buy two lengths and have to find some way of keeping them parallel by tying them together somehow. I'm going to ignore curved track for now, since homemade solutions are complicated to say the least.

Server Cable RailThe solution I chose is somewhat a product of our location. Being located in silicon valley means there are a lot of computer hardware recyclers and resellers. That's great for building a spaceship. I was wandering around WeirdStuff and I came across some huge server racks and related accessories. The cable rails caught my eye. They're made of relatively thick-walled rectangular steel tubing, joined by cross pieces. And best of all they were powder coated black.

I haven't decided what to do about joining lengths of the rail together smoothly, but some of them were 12 feet long so that might not be an issue. Going with this track though mostly rules out a ride-on dolly. It's only about a foot wide, so making a dolly wide enough for a rider would probably be unstable. That's okay with me since I've got a different idea: keep the camera low (for stability) and near the track and raise the track to the height you need. I plan on using a hi-hat for my bogen 519 tripod head and building a rolling base for that. Something as simple as sawhorses can raise the track up with the added benefit of making leveling easier and eliminating shims altogether. The track is rigid enough for this application.

I plan on using the Manfrotto 325B hi-hat. That may not exactly sound like it fits with my low cost plans and that might be true. But we need a hi-hat for low angle shots anyway, and the 325B provides a 100mm bowl interface and has convenient mounting options. It can be mounted to this skateboard dolly, I can build a skater dolly (yeah, it's different), I can use it as a base to attach my tripod head to a crane and in plenty of other situations. So it's more or less an investment for multiple projects and that's one of my core philosophy when building new equipment; I could go for the really cheap solution now and build again later or I can get the one semi-expensive piece now and make it interchangeable and useful in a multitude of situations. A lot more bang for a little more buck.

This post is getting very long now, so check out the next part of the project. I promise it will be more about the specifics and details of the project and probably more to the point (but I can't promise I won't ramble).