Uh oh, maybe I better cancel that 285
The Singer model 285 was a development of the 185 model which it replaced. The 185 had in turn a few years earlier been a cosmetically re-packaged version of the long serving model 99K, re-using many of the same parts as the 99. Although the 285K looks almost identical to the 185K it had a competely new oscillating rack and pinion drive arrangement to the lower hook mechanism under the bed. Unfortunately this 'improvement' was not well received, as it tended to make the 285 machines both noiser and subject to vibration.
At least I'm not paying 75 to over 100 dollars plus shipping.
I will give the little bugger a go for 25.00