bi-rotor
The Bi-Rotor story
Everything started in a little town named Burr Oak
in north central Kansas.
Mark Underwood grew up on his parents farm and later became one of the dryland farmers there. Always thinking
and tinkering, he first thought about a rotor to thresh grain in 1971,
while he was still in high school and at a summer job operating a cement
mixer. Mark gained much of his combine knowledge, being his fathers
combine operator during some custom harvesting years. With the help of a
KTEC grant a two third scale model of the Bi-Rotor was built and tested
a K-State in 1990. Constantly improving and shaping the idea in his
mind, the first fullsize Bi-Rotor combine was built in winter 1990/91.
Mark engineered his idea into a 1480 IH axial flow. The Bi-Rotor
assembly measured only 4 feet in length and 3 feet in diameter, about
the size of a commercial cloth dryer. The IH axial flow rotor was about 9
feet long.
The "new" combine was painted white and therefore called Whitey.
The harvest season of 1991 was the first
time Whitey could show its full potential. One day some CIH engineers
came out to Burr Oak to see Whitey harvesting. Encouraged by its
performance Mark's cousin Ralph Lagergren teamed up fulltime to take on
the marketing and financing side of the venture, that was now called
Agri-Technology L.P.. The cousins decided to built a complete new
combine from the ground up, that would incorporate many more of Mark's
inventions.
In early 1992 they had rented shop space from a small company named
Kincaid Equipment Manufacturing in Haven, Kansas. Many of Mark's
inventions had not made it through the patenting process yet. Therefore
this big project needed to be kept as secret as possible. The
engineering of the XBR2 (experimental Bi-Rotor 2) took much more time
and money than the cousins expected. Therefore Whitey was harvesting the
92 wheat crop around Burr Oak again. Mark had added self leveling
sieves. This time a John Deere engineer witnessed the combining but
again without any follow ups. Whitey got to harvest the corn as well and
grocery money got as scarce as investors for the Bi-Rotor. The end
seemed near, but the unexpected happened again. A company Ralph had
never considered to have any interest in a combine called one day in
fall 1992. Caterpillar had been manufacturing combines a long time ago
but sold its combine division to John Deere in the 1930s. The launch of
its challenger tractor in 1987 showed more interest in agriculture.
After going through a shrinking construction equipment market causing
heavy losses for the company, Caterpillar was now looking for new
markets. Experiments with the CAT tracks on John Deere and Claas
combines were found a too expensive option for the market. To have their
own combine was much more desirable, but CAT did not have any combine
knowledge or engineers to built one. A nondisclosure agreement was
quickly signed. Than the CAT delegation got to see Ralph's presentation
and Whitey. During the long months of negotiating with CAT the cousins
moved their engineering and manufacturing utensils to a new facility
provided by Gordon-Piatt Energy Group located between Winfield and
Arkansas City in Kansas. Gordon-Piatt became an investor in the project
and provided parts manufacturing. In February of 1993 the first CAT
project contribution arrived in form of a used Challenger tractor to be
dismantled for parts and a new set of tracks. Since a modern combine,
even as simple as the Bi-Rotor, has some 30,000 components, much help
was needed to get things going. Glenn Jackson a CAD engineer from Texas,
who had helped building Whitey, Jeff Hawkins, a self-taught welder from
Kincaid, Alan Van Nahmen, an ag equipment connoisseur with 12 years of
John Deere experience and a track zealot, once a factory school
instructor for electrical, power train and hydraulic functions and
Sushil Dwyer, a Ph.D. candidate who had helped the cousins do their
testing at K-State, after he had immigrated from a University position
in India's wheat belt, got hired onto the Bi-Rotor team. Everyone of
them shared Mark's and Ralph's enthusiasm for inventions in general and
the Bi-Rotor. By the end of March the team began to work, by the end of
May the frame was completed. A high profile CAT meeting on August 19th
forced a deadline onto the team. Ralph answered by hiring more
"enthusiasts". Joe Lutgen, a K-State graduate and CAD whiz helped
designing components, while Glen's father Ken, a well experienced civil
engineer and construction supervisor, became Mark's right hand. A ninth
enthusiast was found in Aaron McKee, a K-State engineer student at the
time. The closer the deadline came, the longer the working hours got.
Everything seemed to take twice as long as hoped. Fears were setting in.
Mark had already sacrificed the farm for HIS combine. Joe wound up
designing the 400 bu grain tank all by himself and was worried to death,
that it might not fit, but it did fit perfectly. To eliminate moving
parts Mark wanted most parts driven by hydraulic motors mounting in a
major plumbing challenge of a giant hose and pump jungle. While the CAT
dead line closed in, side panels and painting had to be done, too,
besides a two day haul to Peoria. To help the crew Caterpillar sent a hydraulic
expert with prototype experience. On August 11th at 9:15 AM the 300hp
heart of the XBR2 pulsed for the very first time. At the same time the
side panels were fitted. Then a two day hydraulic troubleshooting period
worried the whole team again. Friday August 13th the malfunctioning
pump was determined and by 10:10PM the tracks were moving as planed. The paint came
on over the weekend and Monday was the journey to Peoria. The internal
CAT show seemed a success, but now the CEOs asked for prove of
performance. Two month of patience robbing "little stuff" went by before
the XBR2 went to the field for the first time in its life on October 7th
1993. On a cloudy and muggy day Mark's invention put clean milo into the
large grain tank behind him as he made eight rounds around the field,
before the rain ended the joy run. Everything worked flawless. A few
days later the XBR2 showed its corn performance on the farm of Mark's
parents. Then the struggle with Caterpillar set in. In lack of combine
experience the company was looking for help to evaluate the Bi-Rotor's
performance. It was found in a major ag equipment manufacturer, that was
supposed to market the new combine in the future. Unfortunately this
company had its own line of combines and could not be believed to conduct
an unbiased test. A Bi-Rotor test unit had to be built to perform as a
test rat in New Holland's research facility in Europe. The test
went well, with minor adjustments, that improved the Bi-Rotors threshing
performance. In spring 1994 CAT and NH suggested more tests in the top
yielding wheat of California's Imperial Valley. New Holland had just
developed their new TX model. The prototype built by some Kansas
"loonies" had to run side by side with two market ready NH machines
designed by a multimillion Dollar R&D department. For some reason
($$$) the NH
combines always came out on top during the tests. Then came the bad
news. CAT pulled out and gave up its rights on the Bi-Rotor.
The team pulled together. Once more Ralph found the resources to
continue the venture. Back at Gordon-Piatt, the guys worked hard to
refine their baby. In 1995 negotiations behind closed doors finalized
the fate of the Bi-Rotor. John Deere bought the patent rights and
shelved it
For more details on Mark, Ralph, the XBR2 fellows and lots of American farming history, please read the book "Dream Reaper" by Craig Canine.
The only videos known to me are in the archives of Legleiter Video Productions, Arkansas City, KS.
Today Mark is working a job in a factory. Whitey and the XBR2 are still sitting beside his shop near Burr Oak, Kansas.
Mark Underwood in front of his engineering marvel.
For more photos and details click on the following pages:
rotor concave drawings
animated pictures of the XBR2
some outdoor photos
pulling the rotor-concave
unit