OutdoorKing Repair Forum Forums The History Forum Model Histories AUSTRALIAN Rotary Models OGDEN ROTAMATIC - c1955

PART 2 - SPECIFICATION

The Engine was the 'Trojan Major', a larger version of the 'Tor 49'.
The Major had a three ball-race crankshaft, deemed obligatory on rotary mowers.
The engine had the old lanyard start - no recoil start was offered.

I think the cowling was made by Ogden, but I'm not sure...



The Rotomatic had a more-complex engine protection system than what was needed.
The swing-blade system used on other rotaries - including Victas, right from the prototype onwards -
was a simple, elegant shock control system for blade holders directly attached to the crankshaft.

Instead, Ogden used rigid-mounted blades (to the blade holder) and incorporated a spring clutch to
protect the motor from shock loads. [see image below]



The Rotamatic had an old-fashioned height adjustment system and rope-pull starter!
By 1957 the mower catchcry was 'automatic'. On the Rotamatic each wheel had to be manually adjusted
for height (a la Americana).



The Rotamatic had a deep-skirt aluminium base that would have offered some safe protection from
projectiles. However, this was not a double skirt design, which would be paramount in later 1960's lawnmower designs.



Here is a specification taken from my 1950s Mower Maintenance Guide:-