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Unfortunately, with only two examples found, details of the Perfecto milling machine are scanty. However, it appears to have been arranged like the Dore Westbury, Beaver Mk. 1 and Elliott Ominimil 00 with its vertical head carried on a ram that could be slid backwards and forwards and drive from a rear-mounted motor to the spindle by V-belt. Unusually for a small miller the ram, instead of being the expected round steel bar, was of the much more rigid dovetail type with the head arranged to swivel on the end, Bridgeport style. In addition to the vertical head, the miller also had a horizontal spindle, driven by V-belt countershaft system from a second motor mounted on the left-hand face of the column; this drive was (usefully) equipped with a low-speed, lathe-like backgear system almost certainly borrowed, judging by its appearance, from the Perfecto lathe. Oddly, instead of using the dovetail ram as the overarm to support the end of a cutter-holding horizontal arbor, the makers employed a round bar that passed, in the usual way, through the column just above the spindle line.
Travel of the standard table - which seems to have been that used on the Dore Westbury miller - had a longitudinal travel (Y axis) of around 14 inches, in traverse (X axis) of just 2.5" and vertically (Z axis) of around 6 inches. As few can have been produced - and the small factory lacked resources - ancillary items like countershafts and bracketing have a decidedly home-made appearance, showing that each example would, almost certainly, have been built to order.
An owner reports:
Using an ordinary end mill with a depth of cut set to approximately 40 thou - or a 60-deg dovetail milling cutter set to take off 120 thou and using a slow feed rate - no chatter was evident. However, as one might expect with such a relatively light machine, with a slab cutter (straight or angled cutting blades) mounted and cutting in 20 thou passes caused quite a lot of vibration. I have not used the back gears on the horizontal mill yet as I find I have not needed the slower speed as yet. It seems to be no slouch when cutting metal, unlike the Sieg X1 or similar milling machine that suffer from a lot of chatter no matter what cutters are employed - with those only very slow and gentle feeds can be attempted.
A few problems I have found: the shaft that holds the pulleys for the horizontal drive has no means of lubricating its bearings (or bushes( that I can see - though as yet there is no wear in them (or anything else). The vertical axis has no covers over its slideway and swarf can enter and make the movement stiff.
If you have a Perfecto milling machine, the writer would be very interested to hear from you.
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