Matakana Scaffolding Inc. was awarded the One Wall Center project in Vancouver, British Columbia, with the challenge of providing access for the replacement of windows in the top 17 floors of the 500-ft. oval-shaped, landmark building. A tight schedule and Vancouver’s windy season to take into account led the team to propose 360⁰ access to each floor at a given time. The tool designed to get the job done was a custom-designed 4’x400’ platform that wrapped the building and weighed in at 18,368 lbs.
Now the team needed to figure out how to lift it.
Owner of Scaffcat Staging Ltd. Victor Kilp’s answer to Matakana’s large-scale challenge was 18 Nihon Bisoh Bisomac210 hoists provided to them by the North American exclusive master distributor of Nihon Bisoh, Florida-based, Bee Access Products.
“Scaffcat is our distributor in Vancouver and that’s how we ended up involved on the One Wall project,” says Tom DeJong, vice president with Bee Access. “Most of the time Victor is purchasing standard equipment from us; however, here and there a project requires special equipment and we work together to customize our products for a unique application. Such was the case with One Wall, which was really special—I’ve never seen a building wrapped entirely by a continuous suspended platform before.”
Unique Machine for Unique Project
The Nihon Bisoh Bisomac210 hoists were uniquely suited for lifting the platform at One Wall. DeJong says out of the hoists’ standout features, the most critical was an extra safety feature that comes standard on all Nihon Bisoh hoist
“In addition to a standard overspeed device, we make standard an overload device on each of our hoists,” he explains. “If a platform hangs up, rather than the stress being on the wire rope and connections, the hoist shuts off at a 1.5 safety factor for the load—that 1.5 factor is key.”
But for One Wall, the one-step-further challenge was that the hoists needed to be capable of operating upside down—not something many manufacturer’s take on or allow for man lifting because of the negative impact that motion can create for certain parts of the machine.
DeJong explains: “Some manufacturers use a common worm wheel-type, gear box, when such a gearbox is turned upside down the oil doesn’t get to all the parts; simply a matter of gravity. This means the “worm” runs drier and could cause premature wear. In contrast, the Bisomac210 hoist has a cycloid type gear box, which uses a stationary outside ring and an inside wheel on an eccenter shaft. The power transfer between the wheel and outside rings is accomplished by a series of stainless steel pins all around the ring perimeter so it doesn’t matter which way it’s turned, it’s always lubricating all parts properly.”
Another potential obstacle created by such movement impacts the overspeed safety device. Typically, overspeed devices are calibrated for standard right-side-up operation—the Nihon Bisoh hoists also work properly upside-down without prematurely tripping the overspeed lock.
The hoists on One Wall had 1000-lb. capacities to help reduce the material and wire rope load on the job; and while the unit capacity is not necessarily unique the fact that the project required a 5 to 1 (versus the standard 4 to 1) static load factor was and involved some hoop jumping for Bee and Scaffcat.
DeJong details how they got the rating: “The same mechanical part of the hoist is used on a 1500-lb. model, so the 1000-lb. hoist is actually capable of holding the 5 to 1 static load. But we needed this in writing. So we went back and forth with the factory in Japan until we got a letter that gave the One Wall hoists the 5 to 1 static load safety factor.
Unique Project, Unique Challenges
So Scaffcat had 18 custom-designed hoists to lift this megalith of a platform around the 500-ft. tall oval building—now they needed to make them ascend and descend—simultaneously.
“To move that many hoists in unison requires a tremendous amount of power—too much to lift the hoists in one shot,” states DeJong. “Eventually what Scaffcat and us decided to do was separate the hoists into three groups, with each group of six starting ascent a half second behind the previous set, until they were all running at the same time. When they shut off the same process was followed, and in theory, all the units would be after level.”
Considering no hoist runs the exact speed as another, the 18 hoists were able to be operated individually or all in one shot to keep them level.
The central control system was the key to making that happen. An electrical controls engineer worked with Bee and Scaffcat to design a system particularly for the One Wall job.
Each platform pick up point needed a 3,000-lb. lifting capacity, making rigging the job not exactly a straight-forward process. What Scaffcat and Bee ended up doing was taking a standard 1000-lb. load capacity Bisomac210 hoist and three-parting the wire rope, giving the system a 3,000-lb. hanging load capacity.
“Matakana furnished their own wire rope pulleys, but we made sure the hoist mount and pulleys lined up correctly, so the wire rope bend around the pulleys would always follow the same direction as the travel inside the hoist in order to prevent any reverse bends which reduces the lifespan of the rope and can cause twisting and kinking, especially considering the wire rope was three times the normal length for that travel distance.” says DeJong.
Matakana also furnished their own heavy duty aluminum I-beam capable of supported the higher than normal loads.
There’s no doubt that the One Wall Center project for the associated project team is a career highlight; however, DeJong contemplates that although the project was unique, companies in the business of providing access solutions see equipment customized often.
“I’ve been in this business since the late 80s and still get requests to solve applications today that I’ve never seen before. There are constantly scenarios where standard equipment doesn’t work, and it’s our job to provide solutions.”