An excavator for the hills: story of Kaiser spider walking excavator

posted by Sunil Newatia on April 10th, 2021
Kaiser AG ranks amongst the world’s leading manufacturers of mobile walking excavators today. The first prototype was produced in 1965.
The MUK 2000, prototype of the Kaiser walking excavator, built in 1965.

In the mid-1960s, Josef Kaiser developed a special excavator for deployment in steep terrain. This was a “single-axle” excavator, later to become known as a “walking excavator”. The defining feature of this type of excavator was the absence of a separate travel drive. Instead, the vehicle propelled itself forwards using the boom and bucket as its front foot.

This was nothing new. Similar models were already on the market at the time, one example being the single-axle excavator developed by the British engineer Richard Smalley. However, the well-known machines all proved to be useless when it came to working in Alpine regions with their seasonal streams and steep slopes. This gave Josef Kaiser the idea of developing his own excavator. 

The prototype of the new excavator was built at the premises of Ernst Menzi AG, based not far away in the Swiss town of Widnau, as Kaiser’s capacity was taken up with the production of slurry tankers. As previously mentioned, Ernst Menzi was already a long-standing supplier to Kaiser and the two company owners enjoyed a good rapport. The envisaged collaboration with Menzi related to the production. The product was to be marketed and sold by Kaiser who also took care of the patent formalities in conjunction with the new excavator type. The name agreed for the excavator by the two companies was the MUK 2000, an amalgamation of the names Menzi and Kaiser. 

Practical trials with the prototype were carried out in Schaanwald. On 22 September 1966. Local newspapers reported: “Schaanwald based vehicle manufacturer Josef Kaiser provided the machine on a trial basis and it proved to be ideal for this work. In one hour, this machine can achieve the work of at least 12 to 15 men. The town of Esche once again resembles a neat drainage channel. Stream bank stones which lay covered for years are now visible. The pond-forming blockages and flooding seen in the past have been virtually eliminated. The drainage function has also been fully restored.”
Your good self with MUK2000 prototype at Kaiser museum
The first walking excavator series – the MUK 3000 
The first series of ten walking excavators, type designation MUK 3000, were manufactured in Widnau in 1966. In the same year, Kaiser presented this novel machine at the Olma trade fair in St. Gallen, which was then Switzerland’s biggest exhibition for the agricultural sector. 

Post this show, Josef Kaiser and Ernst Menzi went their separate ways. Menzi subsequently claimed they had developed the excavator and in autumn 1966 began selling it as the MUCK 3000, as their own product under a different name. 
1965 prototype is still gracing its pride of place at Kaiser museum, which I happened to visit in 2016. Kaiser today is the leader in the innovation and technological advancement of spiders.  You cannot expect the same from people who stole the technology, can you?

Kaiser has 18 Spider Excavators currently operational in India and another 16 on the way
Kaiser S2 busy on a ropeway project in Sikkim

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