OutdoorKing Repair Forum Forums The History Forum Model Histories UK & EUROPEAN Rotary Models ROTOSCYTHE: County Model - c1950

Hello ODK History Lovers

I am yet to write about the British Rotoscythe rear-catcher lawnmowers on these
forums. This radical rotary mower was designed and built by Power Specialities
of Maidenhead in the early 1930s. That company relocated to Slough at the end
of WWII, and was taken over by J.E. Shay Limited of Basingstoke.

This History Record discusses a new type of Rotoscythe designed at this time -
the Rotoscythe County, an 18 inch, rear-discharge machine, designed to cut higher
grasses, or where grass catching was not required. Today, we would call these
'utility' lawnmowers.

They sold in small quantities in Australia from about 1950 and were, arguably,
the first, small, petrol-powered rotary sold here post war. Our own petrol-powered
Victa would not appear until the very end of 1952.

I cannot underestimate the significance of Rotoscythe on rotary lawnmower design.
They were way ahead of their time, and the County would influence one of the two
design strands of 1950s Australian rotaries. There were some design changes to the
County, but the general idea may be found here:-




TO BE CONTINUED ...

PART TWO - The Machine

The County Model had an alloy base with an 18 inch cut. It was powered by
the same British Bux 120cc 2-stroke engine as used on the rear-catcher
Rotoscythes, developing a respectable 1½ hp at 3,000 rpm. The engine had
fan-assisted cooling and an alloy cowling.

An obvious feature is the large, thin 'pram-style' wheels. As the County
was not self-propelled, these wheels would have made pushing the machine
much easier than the smaller sizes we see on most small rotaries.

Height adjustment was, as expected, primitive - with individual adjustment
on each wheel, and requiring tools.

I believe the first model had a handle-mounted fuel tank similar in design
and appearance to the other Rotoscythes. The handle was rigidly mounted and
was not foldable. That would be corrected on the later model. Here is an
early advertisement and early 2015 auction photographs of the first model:-







TO BE CONTINUED ...

PART THREE - Blade & Blade Holder

Special mention should be made at this point to the cutting design of the Rotoscythe.
It is quite unusual. This discussion is applicable to all the Rotoscythe models from
this period.

From the earliest days, Rotoscythes employed a fan-shaped blade holder that had
round blades. That seems quite odd, so a bit of explanation is due.

Prior to the rotary cutting action, two types of grass cutting methods were used:
the 1830s Budding reel design; and shortly after, the sickle mower design. The
sickle blades were flat, triangular in shape, and were mounted in series, to form
a 'sickle bar'. These were the 'Hay mowers', more prevalent in agriculture, rather
than horticulture (like lawn mowing).

David Hamilton Cockburn, the designer of the Rotoscythe, realized that a rotary
scything action required flat blades, but somewhat cleverly avoided the requirement
of resharpening these blades by offering a circular blade that could be rotated as
the outer face became blunt.

In the photographs (below) the first photo shows the underside of a County.
Note that it is not fitted with any blades. The blades and fasteners are shown
in the second photo.



[Image: courtesy mytractorforum.com]

TO BE CONTINUED ...

PART FOUR - The Second Version

The second version of the Rotoscythe County makes a couple of changes.
For one thing, the mower becomes more transportable: with handles that can
be easily removed without disturbing the fuel tank, which is now affixed to
the base (not the handle).

The County becomes a more modern machine, embracing the fully cowled engine
and muffler. I can only guess that this occurred post 1954, as there is a
'blind spot' in advertising records after that year.

Here are some photographs of member pcamore's unrestored machine, one with
engine cowl removed; the other with cowling attached.




TO BE CONTINUED ...

PART FIVE - Signifance

I believe the Rotoscythe was the first powered rotary sold here.
My records indicate that both Western Australia and Queensland sold Rotoscythes
from late 1937 to early 1940, when imports were halted due to wartime.

When imports resumed, Rotoscythes were again sold here from mid-1947. This time
a more organised distribution network through State agencies meant the Rotoscythe
was heavily advertised and sold in most States, and through some large stores.

The Rotoscythe County was a post-war design that augmented the several rear-
catcher machines on offer. My best estimate is that it arrived here sometime in 1950.

The County was not a sales success here because of one determining factor: price.
At about £75 (pound) they were three times the price of an Australian electric
rotary. The first Victa rotaries were £39 when they went on sale in late 1952,
increasing to the magic number of £49, about the average cost of a 1950s petrol-
powered domestic rotary lawnmower.

Nonetheless, I believe a smallish quantity (perhaps hundreds) sold to State
and municipal bodies, including councils and schools.

These are rare and desirable machines. They represent the petrol-powered rotary
before Victa and the 'rotary revolution' that occurred from about the mid-1950s.

The design of the County is significant. The high skirt base and large, thin
wheels clearly influenced Australian lawnmower design, particularly the Ogden
Rotamatic and the rare Melbourne Malvins.

The rest is history.
-------------------------------------
Jack

Bux Engine
https://www.outdoorking-forum.com.au/forum/ubbthreads.php?ubb=showflat&Number=69821

Rotoscythe Rear Catcher
https://www.outdoorking-forum.com.au/forum/ubbthreads.php?ubb=showflat&Number=27168

Malvin Mower
https://www.outdoorking-forum.com.au/forum/ubbthreads.php?ubb=showflat&Number=60956


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