Hello Cirillo and sb30inch

This is such a fascinating topic, and sb30inch has done a better summary
than I could have done.

The issue of front roller design seems to be a combination of theory
and fashion.

The original 1830 Budding patent was 'defective' in that the front roller
was placed behind the bottom block (sole plate and bedknife). Here is a
reproduction machine.

[Linked Image]

The problem with that design was that there was a tendency to scalping,
and Thomas Green (Green's mowers) sorted that with moving the roller
in front of the reel. Other experiments were conducted, including small
side rollers and/or pivoting wheels.

For historical reasons, countries have adopted their preferences.
Euro reel mowers have stuck with one piece or multiple front
rollers for fine lawns. They accepted the argument that the front
roller would hinder the cutting of higher grasses, and so
offered side rollers or wheels on commercial machines for parks
and road verges...

[Linked Image]

The thing is, that USA lawnmowers favoured the side roller/wheel
designs - even for good lawns. I think this is closer to fashion than fact.

The theory was that a full piece or multiple piece front roller would
'push down' the grass before the reel could cut it.

The UK makers rejected that argument for fine lawns - they recognised
that a well-balanced machine placed minimal weight on the front roller,
but the front roller did contribute to the 'stripes' the UK loves,
and it certainly prevents scalping.

AUS makers have taken the UK approach.

The issue of one-piece or multiple piece front rollers is probably
academic. In theory, a multi-piece might make turning easier for
all but straight lines when the front roller is on the ground.

The ribbed front roller only appears on professional equipment.
The theory is as sb30inch has described. I guess it's a sort
of compromise between the two reel mower roller philosophies.

These are my thoughts anyway.
--------------------------------
Jack