HOW THE BOBCATTM SKID-STEER LOADER CAME TO BE

By Joe Keller

 

In the fall of 1947 a small business, Keller Manufacturing, was opened in Rothsay MN.  The photo is of the first of three locations in Rothsay.  Louis Keller was the sole owner/operator until 1953 when his brother Cyril Keller joined him as an equal partner.  At that time Keller Manufacturing was a general repair and fabrication business.  During the time between 1947 and 1953 the most significant product developed was the first single stage ribbon auger snowblower.  Snowblowers from small walk behind models to large truck mounted models were produced at Keller Manufacturing. 

Because of a miscommunication between Louis and Farmhand, the company that had agreed to mass-produce the snowblowers, the patent application was filed too late and a patent was not issued for the ribbon auger.  Farmhand did manufacture several blowers on a royalty basis for a couple years but then chose to stop production. At the time this seemed like a significant loss but if the blower development had gone full scale, the Keller Loader may not have been developed.

Shortly after Cyril joined the business one of Keller Manufacturing’s frequent customers, Eddie Velo, came to Louis and Cyril with a problem in the summer of 1956. Eddie was one of the pioneers in the turkey industry as it was going from small flocks to large producers utilizing large two story barns.   Eddie was finding it more difficult to get the manure cleaned out of his turkey barns. Standard loader tractors couldn’t be used because of their limited maneuverability, plus they were too heavy to operate on the second story. 

Some time went by but the Kellers didn’t forget Eddie’s problem.  After a drive system was designed that had the possibility of providing the maneuverability required (see photo), Eddie agreed to pay a fair manufacturing cost for the loader if it worked.  If it didn’t work the Kellers would forfeit their time and Eddie would pay for the materials since many of them could be used for general repair jobs. 

On February 4, 1957 the first loader was delivered to Eddie (see photo) and the testing began.  Eddie provided unlimited access so the Kellers could observe the loader in use and perform modifications as required.  The loader surpassed expectations from the start.  However the belt drive proved somewhat hard to operate and also control of the loader was lost if a belt slipped off a pulley.  This led the Kellers to design and patent a clutch system eliminating the belts.  This drive was later installed in Eddie’s loader.

Sometime after February 4, 1957 Keller Manufacturing started production of more loaders.  These loaders had the same design as Eddie’s with minor modifications to enhance the manufacturing process.  They were, with the exception of the last one, powered by a 6.6 HP Kohler Engine.  By the fall of 1958, six more Keller Loaders were built and sold to various poultry farms.  During this time the Kellers were also actively searching for a way to mass-produce their loader.  The bank at Rothsay was willing to put up part of the $250,000 required for a manufacturing facility but wasn’t able to supply it all.  The bank approached the city for the rest but wasn’t able to get enough interest to raise the remaining money.  The city of Fergus Falls, MN was also approached.  They were willing to supply the money but also wanted controlling interest in the patent.  This was unacceptable to the Kellers. 

Also during this time the Kellers uncle, Anton Christianson, introduced them to Les Melroe, of Melroe Manufacturing Company, Gwinner, ND.   Les stopped by Keller Manufacturing when they happened to be replacing the original belt drive on Eddie Velo’s loader with the more reliable patented clutch drive system.  Les was impressed enough to invite the Kellers to bring a loader to the Melroe booth at the 1958 Minnesota State Fair.  The Kellers did have one loader that hadn’t sold yet (see photo) so they accepted the invitation.  There was no real effort to sell loaders at the Fair although the sale of the last Keller Loader was a result of this display.  The main purpose of the display was to determine the amount of interest in the loader.  The interest was so great that Melroe said they wanted to manufacture the loader.  After the Fair, an agreement was reached where Melroe would have exclusive manufacturing rights on a royalty basis.  The Kellers would be employed by Melroe to further develop the loader since all of Melroe’s current employees were needed to continue production of the coil spring tooth Harroweeder and Windrow Pickup attachment for combines.  In late fall of 1958 Louis and Cyril rented an apartment in Gwinner, ND so loader development could begin.  They commuted home to Rothsay on weekends.  Eddie Schillinger continued to operate Keller Manufacturing for 18 months until the business was sold at auction.  Eddie then moved his family to Gwinner and started his career with Melroe. 

Development of the first Melroe loader prototype was started November 1958 and was completed early in 1959 (see photo).  The prototype had the same patented drive design that replaced the original belt drive in the first Keller Loader, which was used on various models until 1982.  Other similarities to the Keller Loader were two independently operated front drive wheels, a caster wheel in the rear, two-levered steering, and the bucket and lift arms operated by foot pedals.  Access to the Melroe facilities allowed this model to be larger and have a more professional look.  It utilized the same 9 HP, model AENL, Wisconsin Engine used on the last Keller Loader and the rear portion of the frame was fabricated from steel plates.  After some testing they started fabrication of five more loaders.  When these were completed Cyril went on the road selling and Louis continued loader development.  At this time Louis moved his family to the Gwinner area.  Cyril’s family stayed in Rothsay several years since he was on the road selling loaders most of the time.

The first production model, based on the six prototypes, was the M60 Self-Propelled Loader.  The M60 had two production versions.  The first was the same as the original six prototypes (see photo) The records are unclear as to how many of this version were produced but everyone agrees the number is low.  The second version, M60 Improved, had two modifications.  The rear portion of the frame was know a casting and the Wisconsin engine was replaced with a 12.9 HP 2 cylinder ONAN engine (see photo).  Both of these versions had the same boom upright configuration.  This configuration was nicknamed the “Grasshopper” boom.  

The second Melroe model was the M200 Melroe self-propelled loader (see photo).  This model was similar to the M60 Improved with two exceptions.  First, the boom upright was changed to a more easily fabricated straight version.  Second, the color was changed to Farmhand red and implement yellow.  These first two models worked well on the hard surfaces typical in the poultry industry.

The third Melroe model was the M400 Melroe self-propelled loader developed by late 1960 (see photo).  This was the first four-wheel drive skid steer model.  The inspiration for this model was the hard times in the poultry industry and the need to develop markets in areas where hard surface operation wasn’t an option.  Removing the caster assembly and adding the second axle was generally not seen as an option that would work and was viewed as not worth the dollars to even try. Louis felt it would work and modified an existing M200 to accept the second axle.  During the first try the loader wouldn’t turn until Louis realized the variable speed pulley wasn’t engaging correctly.  This is when the first skid-steer loader went spinning into the history books.

Sales took off again when the M400 version hit the market.  The same basic machine was sold with either the M200 or M400 option.  There was also a kit available to convert previously sold M60s and M200s to the M400 configuration. The combined sales of the M60, M200 and M400 loaders totaled about 700.

During this time a larger prototype three-wheeled version was fabricated (see photo). It was a little more than twice as large as the M200 and was powered by a 24 HP two cylinder Kohler engine.  After the first M400 was produced this larger prototype was also converted to four-wheel drive configuration.  Since the sales of the M400 were doing so well the decision was made not to put this larger version into production and therefore only one was ever fabricated.

New markets created new problems for the M200 and M400.  The most significant problem was corrosion in the exposed drive system, especially in the fertilizer market.  Debris was getting in the exposed drive system causing chains to jump off sprockets.  There was also a need for double acting cylinders on the lift arms to enhance the ability of the loader to perform well in hard soil. 

The first attempt at solving these problems was a prototype that had a similar appearance to the M400 with the same 12.9 HP ONAN engine (see photo).  The changes made were the drive compartments being sealed with chains and clutches running in oil and the lift arm cylinders were double acting allowing them to apply downward force on the cutting edge of the bucket.  When this machine was in the testing phase it was difficult to keep it functional for long periods of time.  The frequent breakdowns were attributed to the increased weight/traction and increased digging ability with the double acting cylinders.  Because of this only two were fabricated and only one reached the testing phase.  The undocumented theory is that it wasn’t sold but scrapped at the Melroe facility.  The second one never quite reached the end of its fabrication stage.  As can be seen in the photo it was primed but was never painted or used.  This loader never left the Melroe facility and has been restored.  These machines were nicknamed the Clyde Olson loaders because they were the last ones Clyde worked on before he took a job in Glenwood, MN.  Clyde had helped with the fabrication of all the prototypes up to this point.

A second prototype was designed using the same ONAN engine but went away from the M400 tapered drive compartment look and the entire machine was made stronger.  This prototype tested well and became the next production model.  The M440 Melroe Bobcat, the first model to receive the Bobcat name, entered the market late 1962 and sales continued to increase (see photo).  It was the first production model to have the enclosed drive compartments and double acting cylinders.  It was also the first production model to be painted white.  The white color was chosen because of two new markets that were being pursued: the fertilizer and dairy markets.  The white color hid the fertilizer dust and signified the cleanliness required for the dairy market.  The final significant change to the M440 was that it was the first to have the necessary 70/30 back to front weight distribution required to make a skid steer loader turn easily.  Without a load the front end skids easily and with a full load the rear skids easily.  This made the M440 the first true skid-steer loader. 

Lynn Bickett originated the Bobcat name.  When he looked up "bobcat" in the dictionary, he saw that it is a North American mammal that is "tough, quick, and agile".  Since these traits perfectly described the M440, it became known as the Bobcat skid-steer loader and the Bobcat slogan, “Tough, quick, and agile”, was born.  

In late 1963 the next production model was the M444 Melroe Bobcat (see photo).  The only difference between the M440 and M444 was the M444 had pressurized oil supplied to the clutch systems. 

With the increased strength designed into the M440 and M444 it was decided to install a two-cylinder 24 HP Kohler engine in the next production model. With only this significant difference the M500 Melroe Bobcat (see photo) was marketed in 1964.

The next two production models kept the same basic design as the M500 with the exception of minor modifications for increased power.  The M600 Bobcat had a four-cylinder 25 HP Wisconsin engine and the M610 Bobcat had a four-cylinder 30 HP Wisconsin engine.  The M600 sales began in 1968 and the M610 soon followed.  Production continued on the M610 until 1982.

All the Melroe models mentioned had the same patented clutch design drive.  With the exception of specialty models (electric motors, propane engines, etc.) only one more model utilized the same drive system.  This was the M371 Bobcat, which was nicknamed the Mini Bob.  The first two prototypes were designed and fabricated in Louis Keller’s shop at his home 5 miles north of Cogswell, ND.  Leland Erickson and Roger Albertson helped in the design and fabrication.  The M371 entered the market in 1971 (see photo).  This was the first model designed to fit through a 36” wide opening.  It was also the first model to have the drive compartments, previously located on the sides, integrated into one compartment located in the lower center of the machine.

In the later years of M610 and M371 production early hydrostatic models were being developed and sold.  The hydrostatic models have been very successful and have given the modern Bobcat skid-steer loader (see photo) the market share it has today.  Many models were introduced between the M610 and this one.  This is just one example of the progress that has been made by the Kellers, Melroe, and Bobcat since Eddie Velo made his request for a light, highly maneuverable, inexpensive, and easily maintained loader to clean his turkey barns.