An Overview of the Beeman Tractor Design

Model G

• The Beeman Garden Tractor, The First Successful Walking Tractor (I think)

Note:  All dates/numbers/measurements are suspect because I'm writing this from a VERY POOR memory!

The Beeman tractor, as first envisioned and drawn on the patent application, was pretty close to what it looked like when it actually made it into the field. 

The tractor featured:

·        two cast iron driving wheels,

·        a one cylinder water cooled engine,

·        open flywheels (counter-rotating within the wheels),

·        an oil bath clutch,

·        one speed forward, based on engine speed,

·        no reverse,

·        trailing implements, and

·        minimal ground clearance.

The Engine

The engine ran quite slowly, typical of the engines available in 1915.  It was a vertical engine, utilizing an L head layout, and was reasonably well protected from the dirty environment in which it ran.  My Beeman uses a Bosch magneto, with a leather disk coupling, and a Kingston carburetor.  The engine is cooled by a Shottwell-Johnson cellular radiator and a belt driven fan.  The fan draws it's power from the magneto drive, certainly an interesting arraignment. 

The engine, clutch, and driving gears are all contained within a common oil sump, with the exception of the final drive gears, which are outside of the crankcase.

The engine uses a 4 inch diameter piston and a 5 inch stroke.  16 ?? inch diameter flywheels (one inside of either wheel) round off the engine description.  Note, you can date your tractor roughly by what is cast into the wheels.  If it says "New Beeman Tractor Company" then it must be a post-'24 tractor.  If it says "Beeman Garden Tractor Co." then it likely dates from before 1921.

Final Drives

The engine's power is transferred to the wheels through a set of pinions riding inside the wheel hub.  This hub is cut with gear teeth also, to mate with the pinions.  This results in a drive system akin to that of a solid axle (no differential).  The wheels (cast iron) also run on cast iron journals.  These journals serve a dual purpose.  The crankshaft runs inside of them, and the wheel turns on the outside of them.  The bad news is that the lubrication method for the wheels was very dependent on the operator making good use of his grease gun, and most of the time, they didn’t.  So if you find a Beeman tractor, expect to have to do some extensive machine work getting the wheels to run correctly again.

Humor

The original Beeman tractor sold without an air cleaner.  However, you could purchase one with the tractor for an extra $5.  In the fine print of the contract, it was noted that the warranty was void if you did not buy the air cleaner at the time you bought the tractor.   Hmmmm…

Other Mechanical Issues and Commentary

The tractor weighs quite a lot, I would estimate it at around 700 pounds with it's trailing carriage, but I haven't put it on a scale yet.

The ground clearance is terrible, about 7 inches.  The only way to use the machine practically would be to run it between the rows.  For a crop like onions, this would not do, of course, as it would use too much land per row.  Since the tractor is roughly 20 inches wide (I believe the "official" width is 17 inches), you can see that you would have to set out 2 foot rows at least.

The trailing implements are pretty massive.  I expect the tractor has  more power than it can apply to the ground, and more tractive effort than the designers expected it to have.  The first implements (from the 1915 field tests) were little scratching tools for basic weeding and so on.  Clearly the tractor could pull more than this, as evidenced by the massive trailing carriage that came with my 1925-ish model.

It's amazing that this machine was still being sold in the '40s as it's design was outdated by 1925.  Putting my 1928 Viking Twin next to the '25 Beeman is a real eye opening comparison, just as comparing the Viking to a 1940's tractor.   It would appear that any given design was outdated just a few years after it went into production.  Sounds like the High-Tech market of today… which, of course, it was for it's time.  75-80 years ago, growing food was big business, but it wasn't necessarily dominated by big businesses.  These small machines put food on the table for lots of people.

You can mail to me here: markb@umr.edu