Ancient engineering inspires a new approach to moving some of architecture’s heaviest doors

Taking inspiration from the structural principles behind the Roman arch, CiiLOCK Engineering’s Mother of All Rollers uses an unusual self-levelling mechanism to help architects and fabricators create larger, heavier sliding doors without allowing the hardware beneath them to dictate the design.

As architectural doors become larger and glazing becomes thicker, the hardware hidden beneath the panel is being asked to carry increasingly significant loads.

For CiiLOCK Engineering, this presented an interesting problem. Increasing the size of conventional sliding door hardware can provide additional capacity, but it also requires more space within the door profile - often working against the architectural preference for slimmer framing and larger areas of glass.

The solution eventually came from a much older form of engineering.

“The inspiration behind the Mother of All Rollers was the Roman arch,” explains Simon of CiiLOCK Engineering. “An arch is able to carry enormous loads because the individual elements work together under compression. We started looking at whether we could apply a similar principle inside a sliding door roller.”

The result was the Mother of All Rollers, commonly referred to as MOR.

Rather than relying on a conventional multi-wheel bogey arrangement, MOR uses a pressure-based, self-levelling mechanism inspired by the keystone structure of an arch. As load is applied to the roller, the mechanism helps distribute that load across multiple wheels, allowing the wheels to work together rather than concentrating the weight through only a small number of points.

“One of the challenges with simply adding more wheels to a roller is making sure they are all actually carrying their share of the weight,” Simon says. “If the running surface or the door varies slightly, some wheels can end up doing more work than others. MOR was developed to allow the structure to respond under load and help maintain more balanced wheel contact.”

This ability to distribute load also allows CiiLOCK to approach roller design differently.

Instead of offering a single fixed roller and asking the door manufacturer to design around it, MOR can be configured around the requirements of the door. Roller width, height, wheel arrangement, materials, load capacity and adjustment can be selected to suit compatible aluminium, thermally broken aluminium, timber, uPVC and other framing systems.

The need for this kind of solution becomes particularly relevant as modern doors incorporate heavier glazing.

Double and triple glazing, acoustic glass and increasingly large panel dimensions can add considerable weight to a sliding door. At the same time, architects are often trying to reduce visible framing and create cleaner connections between internal and external spaces.

“The roller is a very small part of the finished door, but it has a disproportionate effect on what can be achieved,” Simon explains.

“If the hardware requires a large cavity or has a limited load capacity, that starts influencing the frame, the glass and ultimately the architecture. Our approach is to understand what the door needs to do first and then engineer the movement around it.”

The modular nature of MOR means the same underlying technology can be used across a broad range of sliding door applications.

Precision-engineered polymer wheels can be used where quiet, smooth operation is important, while wheel numbers and carriage dimensions can be varied according to panel weight and available profile space. Materials and corrosion protection can also be selected around the environment and application.

At the extreme end of the range is MOR One-Tonne, an engineered continuous roller system developed for exceptionally heavy sliding panels.

Rather than supporting the door through several concentrated roller locations, the custom-length assembly distributes the panel load across multiple wheel positions along the base of the door. In approved project-specific configurations, the system can be engineered for sliding panels weighing up to 1,000 kilograms.

“A one-tonne sliding door is obviously at the extreme end of what architects are likely to encounter, but it demonstrates what the technology can do,” Simon says.

“When you reach that sort of scale, you cannot think about the roller in isolation. The panel, frame, running track, structural support, alignment and deflection all become part of the same engineering problem.”

For these applications, MOR One-Tonne operates on a properly supported solid stainless-steel running track, with panel mass, frame stiffness, track geometry, support conditions and maintenance access considered as part of the project-specific engineering process.

Although the one-tonne system makes an impressive demonstration of the technology, Simon says the broader value of MOR is its ability to give designers and manufacturers more flexibility at more conventional door sizes as well.

“The objective isn’t to make every door enormous,” he says. “It is to avoid the hardware becoming the reason an otherwise good idea cannot be achieved.”

For CiiLOCK, this type of thinking reflects a broader view of architectural hardware.

The components controlling movement may be largely invisible once the door is installed, but they determine how the final product moves, feels and performs. As doors become heavier and more technically demanding, CiiLOCK sees that movement hardware as an increasingly important part of the overall system.

The Mother of All Rollers is a particularly literal expression of that philosophy: a modern sliding door technology built around an engineering principle that has been carrying enormous loads for thousands of years.

And while the mechanism itself remains hidden beneath the door, the architectural possibilities it creates are considerably easier to see.

Learn more about CiiLOCK Engineering