Unknown until discovered in 2016, the Crosthwaite lathe looks to have been a product of the 1950s. With a capacity of approximately 3.5" x 16" and looking very similar to the Myford ML4 and Perfecto, it was of conventional layout for a small English lathe as built until the mid 1940s. Flat topped, the bed had V-edged ways and carried a short carriage topped by a compound slide rest. Backgear (clustered immediately inboard of the front headstock bearing) and screwcutting were both fitted, together with a tumble-reverse mechanism for the changewheel drive to the leadscrew. The specification included the usual T-slotted cross slide, a 3-step V-belt pulley on the headstock spindle and a tailstock the barrel end of which was threaded and passed clean through the handle.
Of the simplest kind, the headstock spindle bearing were spilt bronze sleeves closed down by pinch bolts at the front; the owner of the machine below has, wisely, fitted drip feed oilers in place of what would probably have been just open holes when the lathe was new.
One improvement over the ML2/Perfecto was a cross-slide screw supported in an extended bracket bolted to the front face of the slide (just like that on a Myford ML7) this arrangement giving an extra inch or so of useful travel for the occasions when a milling slide was in use.
Drive came from a robust countershaft - again modelled on that used on the pre-WW2 Myford ML2 to ML4 range - with the motor mounted against its back face. Even the tailstock copied the dreadful one employed on early Myford lathes - though the side-plate adjuster arrangement looked to be much stronger and may have even allowed the best efforts an owner to maintain alignment in the face of hard work.
Unfortunately the only pictures available to date are of low resolution - but it is hoped that improved ones might become available, Should any reader have a Crosthwaite lathe, the writer would be interested to hear from you..