May 2005

Porta-Glide Wheels
Porta-Jib presents a design for skateboard-style dolly wheels eliminate the need to “rock out” more

Current Products
Back to the current New Products and Services. go

Porta-Glide Wheels
Those who have worked with skateboard-style wheels on dolly track — with full-sized Fisher or Chapman dollies —  know that the wheels can be both a blessing and a curse.

The most significant problem with these rigs is that in order to create the smoothest ride possible, the wheels needed to be of a relatively soft composite plastic/urethane to smooth out imperfections in the track. However, this soft material creates a problem: once the dolly is parked for a moment or two, its weight bears down on the wheels and creates a temporary flat spot; once the dolly starts rolling again, this causes a bump when the flat spot hits the track again. To solve this dilemma, a dolly grip must “rock out” the bump by pushing the dolly back and forth several times until the flat spot is rolled out. This inconvenience has afflicted all skateboard-style wheels — until now.

The folks at Porta-Jib by Losmandy have come up with a smart solution to flat spots with the new Porta-Glide Dolly Sleds. Since the sleds have 16 wheels in all (four at each corner), Porta-Jib decided to use 16 different wheel diameters — a unique size for each wheel. By adjusting the center positions for unique diameter on the wheel block, all wheels touch the track simultaneously; like those in other systems, these wheels will flatten slightly when the dolly is parked. However, because each wheel has a different diameter, as soon as the dolly is moved, instead of 16 flat spots hitting the track in unison, each of the Porta-Glide wheels returns to its flat spot at a different time, making the flat spots undetectable.

This seemed like a smart approach, and I decided to give the Porta-Glide a trial run by asking dolly grip Dwayne Barr to give it a shot. Barr had worked as dolly grip for AC technical editor Christopher Probst on the aggressively handheld TV series Boomtown (for which Probst served as camera operator), and since then, he has moved on to serve as B-camera dolly grip for cinematographer Jamie Barber on The O.C. Although Barr doesn’t have much call for large moves while working on the B-cam, he passed the sleds along to A-camera dolly grip Michael Landsburg so he could give them a whirl.

Landsburg has been in the business for 17 years, pushing dolly for the past eight years on television series such as Felicity and Without a Trace and on feature films that include Behind Enemy Lines and the last two features shot by the late John Alonzo, ASC, The Prime Gig and Deuces Wild. Landsburg owns his own set of skateboard-style wheels, was eager to try out the Porta-Glide, and spent two weeks putting them to the test in various situations, including a mammoth 300’ move on location.

Overall, he was extremely impressed with the Porta-Glide Dolly Sleds and gave Porta-Jib a glowing review. “The most outstanding feature is the consistency of the skate wheel,” Landsburg offers. “We’ve had absolutely zero problems with flat spots, which is either a result of a really good composite, the various wheel diameters, or possibly both. We’ve had no problems with bumps, even with the dolly sitting still and then rolling immediately. Overall, the construction is good and they’re not too heavy.

“I’ve also noticed that they are extremely quiet,” he continues. “My own track wheels tend to make a kind of whirring sound, but the Porta-Glides are very quiet. This could be due to the fact that they’re brand-new and the bearings are in better shape, but I’ve noticed a pretty big difference, especially in confined areas where sound really matters. They seem to have no resistance on the track and they glide effortlessly, easily taking out all the imperfections in the track. We’re not seeing any gaps, burs or nicks in the track through the lens at all.”

Each of the 16 wheels is identified with a number so that if replacement of any wheel becomes an issue, that specific diameter can be obtained to keep the sled in balance.

Another unique aspect of the Porta-Glide is the design of the rig’s wheel blocks: three pivoting and one stationary. The pivoting arms let the dolly float effortlessly on all traditional curved tracks. Unlike other sleds, the arm articulation means that the dolly being supported remains centered during the curve. To Landsburg, this is an interesting feature, but one that has not quite been perfected: “The pivoting arms became very tedious when we were trying to get the sled up on the track, because you suddenly have three moving parts that you’re trying to align all at once. There’s a hole in the wheel block and sled base so that you can lock the pivoting arms in place with a bolt of some kind, but it would be great to have some sort of quick-release pin that would lock or unlock the arms. Ninety percent of the time when I’m using these kinds of wheels, I’m not using curved track, so I gain no benefit from the free arms; they’re more of a liability when I’m putting the sled onto the track. It’s an interesting feature for that 10 percent of the time when we pull out curved track, but the arms should be able to work more functionally when you’re on straight track. Also, because the arms do pivot, they can almost be folded in on themselves for traveling. If one arm were shorter than the other, they would neatly fold in and be a lot easier to transport.

“Those are really picky comments, however,” Landsburg concludes. “I would give these wheels a triple-A rating, for sure.” (In fact, Landsburg was so pleased with the Porta-Glide wheels that AC had difficulty getting the loaner unit back from him to return to Porta-Jib!)

A set of two sleds lists for $1,495. For more information on the Porta-Glide Dolly Sled, visit or call (323) 462-2855.