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.

[Linked Image]
[Linked Image]
[Image: courtesy mytractorforum.com]

TO BE CONTINUED ...