HAAS : HE213

Mountain folk are innovative. They have to be! However, the Wyssen family, in the picturesque canton of Bern, Switzerland are more innovative than most. Eighty-five years ago, Jakob Wyssen developed an overhead crane system that’s now the industry standard in timber transportation and, increasingly, bridge construction. Three generations later, his three grand sons are using Haas CNC machine tools to continue the family tradition of inventiveness.

In the mid 1920’s Jakob Wyssen bought some land in the mountains near his home in Reichenbach, Switzerland, about two hours or so from Zurich.

The land came with timber. A lot of timber! Like most of his contemporaries and neighbours at that time, the only way he could get the timber down the mountain to his sawmill was manually, which was heavy, labour-intensive work. In 1928, Jakob invented the skyline crane – a simple, overhead cable running from the top of the mountain, to the foot. Along the cable, he was able to suspend a wheeled carriage equipped with a load carrier.

The first skyline crane was manually operated. The carriage was dragged to the top of the mountain where a hook could be let down. The load would then travel back down the cable by gravity. It was a simple, but effective labour-saving invention that quickly caught the attention of mountain woodsmen far-and-wide.

In 1940, Jakob eventually mothballed his sawmill and started Wyssen Skyline Cranes, to dedicate his time to manufacture the skyline crane. In 1944, he developed a semi-automatic carriage. Then, ten years later he began making a fully automated version where the carriage can clamp itself to the cable at any point, from where the hook can be lowered, and the load can be winched up, as the carriage begins to move either up or down the cable. More than 85-years later, the company old Jakob founded is still owned by the Wyssen family and is run by his grandsons: Jürg, Jakob (aka köbi), and Christian. A cousin, Sam, also works alongside the brothers.

Today, Wyssen Seilbahnen AG has 36 employees, 4 of whom are apprentices. Like all mechanical engineering companies all over the world, new recruits are hard to come by, but for the family, Jakob’s ingenuity has provided stimulating and rewarding employment.

The company has two divisions: skyline cranes, and avalanche control systems. The former are built and shipped to customers all over the world, mostly governments or private enterprises managing timber and forestry. “Skyline cranes are very environmentally friendly,” says Jürg, head of engineering. “There’s no need to build or widen roads to get timber down the mountain. The towers have a very small footprint and the load, the timber, travels above the terrain and any obstacles.”

The Wyssen avalanche control division builds an innovation that contributes a growing percentage to the company’s revenues. The avalanche control subsidiary is run by youngest brother Christian, and Sam, the cousin. The Wyssen system uses large, steel towers that are stationed permanently on avalanche-prone mountainsides – everywhere from the company’s home region, to mountain ranges in Austria and northern Scandinavia.

At the top of a Wyssen tower is a circular container, resembling a tub. Inside the tub is a cluster of dynamite charges – usually 12, which can be activated remotely to precipitate an avalanche. When the operator presses the button, the 5kg charge drops down on a wire to just above the snow level, where it detonates. The shock wave dissipates across the snow face causing an avalanche, without damaging the underlying rock.

“Avalanche control blasts are traditionally undertaken from helicopters or by hand, on the ground,” says Jürg. “The former method is expensive, and the latter is dangerous, of course. The Wyssen system doesn’t require good weather, which means the avalanche can be triggered at the most opportune moment after a heavy snow fall, usually before skiers, hikers or climbers return to the area.” Wyssen sells its systems to governments and private ski resorts all over the world.

As well as timber and forestry, the skyline crane is also used increasingly on construction projects, including hydroelectric power plants and large span bridges and suspension bridges. The company’s foyer is adorned with photographs of familiar and less-well known structures during construction. For example: the Norman Foster designed Millennium Bridge over the River Thames, in central London; and The Storebælt Suspension Bridge in Denmark, one of the world’s longest.

Wyssen makes and delivers whole Sky Crane systems, including the carriage, cable, towers, and winches. The company will deliver a complete system for a project, with or without installation. “Some carriages have built-in motors to help them lift very heavy loads – up to 20 tons!” says Jürg. “But, on the way down, gravity does a lot of the hard work. They can be very energy efficient.”

A thousand reasons for Haas
Wyssen bought its first Haas CNC machine tool, a VF-4 vertical machining centre, around 6-7 years ago. A year or so later it bought a Super Mini-Mill and a TM-1 Toolroom Mill. A year after that it bought an SL-20 CNC turning centre and another Super MiniMill. Since then, the company has continually invested in Haas and today, makes almost all of the parts for its crane and avalanche control systems in-house.

“We keeps almost all parts in stock,” says Jürg, “even for machines built up to 60-years ago. Wyssen products are built to last! “Gears are sub-contracted,” he adds, “as are some of the specialist finishes, such as anodising. Grinding, nickel plating, hardening, chroming – is all done outside.” However, each finished Wyssen skyline crane contains around 1000 parts, so there’s no shortage of work for the Haas machine tools.

“All Wyssen parts are designed in SolidWorks. The programmes are created using Esprit CAM and downloaded straight to the machines. A typical part batch is 30-off, so quick set-up time is a priority.” Jürg’s aim, he says, is also to try and machine as many parts as possible in ‘one-hit’.

“The Haas plug-and-play rotary table and 4th axis system was another reason we decided to invest in Haas. The fact that the 4th axis is also built by Haas was very attractive to us. It makes life so much easier when you’re setting up. And, there’s never a problem with the interface between the machine and the rotary table.”

The Haas TL-25 has full C-axis, live tooling and sub-spindle, which means parts can be machined on their back-sides, which removes the need for them to be moved to one of the vertical machines for second or third ‘ops’. The anodized hydraulic manifold block is machined on the Haas VF-4 in two set-ups, both using the Haas 4th axis rotary table. Batch sizes are usually 30 parts, each of which takes around an hour of machining.

For some parts, switching between machines is unavoidable. Batches of 50 of a heavy, steel component around 30cm in length are turned on the SL-20 or the TL-25, before a cross-hole in each is machined on the VF-4. The final operation is the groove, which is also made on the TL-25. The live tooling and the sub-spindle on the TL-25 are used, for example, to bore split pins and to mill studs and special screws.

“The most difficult and technically challenging part we make on the Haas machines is the choker,” says Jürg, “which has challenging geometries, tight tolerances and is made from high-strength steel. It’s milled on the VF-4, also in two set-ups, also using the 4th axis.” Haas machines are distributed and supported in Switzerland by the Haas factory Outlet (HFO) owned and operated by URMA AG, a well-known manufacturer of metal cutting tools and tool holders. Jürg and his brothers first saw the Haas machines at the Prodex show in Basel, Switzerland.

“The head of our machine shop at the time was dead-set on another make of machine tool, also from the US. However, when we were ready to buy, I contacted URMA about the machines I’d seen in Basel. I discovered that a Haas machine with the same spec’ as the machine our shop manager wanted would cost half as much!” Another family member with a nearby machine shop already had a Haas machine. Jürg contacted him and asked him what he thought. “He told me that in 7 years of using the machine every day, he hadn’t had a single problem. That made up my mind.”

Founder Jakob Wyssen’s original profession, Skyline Cranes, still accounts for around 65% of the company’s turnover, and growing markets including Chile and Eastern Europe will help ensure that probably remains the case for a few years to come. But, with the three brothers and their cousin at the helm, and a shop full of Haas machines, new innovations like the avalanche control system will play an increasingly important part in the company’s future. The Wyssen founder’s namesake, Jakob junior (aka köbi) gives the final verdict on the Haas machines: “They allow us to produce the parts we need quickly,” he says. “Because they are similar, and use similar controls, we need very few people to operate them. Since it’s difficult to find machine operators in this area, that’s an advantage for us. It means we can make everything in-house with simple to operate, reliable machines that are very well supported by URMA, the local Haas Factory Outlet. I think my grandfather would have chosen Haas.”

For more information
Web: www.HaasCNC.com