Click ME to close the menu.

Log In to MTD Channels to access your customer cockpit and see content more relevent to you.

HAAS chosen for Wyssen Skyline Cranes
HAAS chosen for Wyssen Skyline Cranes

HAAS chosen for Wyssen Skyline Cranes

Added to MTDCNC by HAAS Automation on 09 November 2013

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 grandsons are using Haas CNC machine tools to continue the family tradition of inventiveness.

In the mid 1920s, 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 started Wyssen Skyline Cranes to manufacture his innovative device. He developed a semi-automatic carriage for the crane in 1944, and began making a fully automated version 10 years later. Today, the company Jakob founded is still owned by the Wyssen family, and run by his grandsons – Jürg, Jakob (aka Köbi), and Christian – and a cousin, Sam.

Wyssen Seilbahnen AG has 36 employees, 4 of whom are apprentices. The company has two divisions: skyline cranes, and avalanche control systems. The former are built and shipped to customers around the globe, 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 that can be activated remotely to precipitate an avalanche. When the operator presses the button, the 5 kg charge s down on a wire to just above the snow level, where it detonates. The resulting shock wave dissipates across the snow face to initiate an avalanche, without damaging the underlying rock.

'Avalanche control blasts are traditionally undertaken from helicopters, or by hand, on the ground,' says Ju¨rg. '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, large-span bridges, and suspension bridges. 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 or 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 Mini Mill. Since then, the company has continually invested in Haas equipment, and today, Wyssen makes almost all of the parts for its crane and avalanche control systems in-house.

'We keep 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, and chroming are also 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.' Ju¨rg’s aim, he says, is also to try to 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,' Ju¨rg notes. '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 backsides, which removes the need for them to be moved to one of the vertical machines for second or third 'ops.' The live tooling and sub-spindle are used, for example, to bore split pins and to mill studs and special screws.

An anodized hydraulic manifold block is machined on the Haas VF-4 in two setups, 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 30 cm in length are turned on the SL-20 or the TL-25, before a crosshole in each is machined on the VF-4. The final operation is the groove, which is also made on the TL-25.

'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.'

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 U.S.,' explains Ju¨rg. 'However, when we were ready to buy, I contacted URMA [the local Haas Factory Outlet] 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 percent 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.'


Building Location

What are you looking for?

What are you looking for?

Fill out this short form and we will do the work for you!

What is 7 + 3? (Spamcheck)