email: tony@lathes.co.uk
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CVA No. 79 Milling and
Die-sinking Machine
A Sales Sheet is available for this miller   CVA Lathes

CVA Milling Machines Page 2


Another beautifully made product from CVA Jigs Moulds & Tools Ltd. of Hove,  Sussex, the well-specified and versatile No. 79 was a toolroom-class machine and intended for precision milling and die-sinking. Advertised from the early 1930s until the early 1950s, as with some other CVA products, the sole selling agents were the well-known dealers E. H. Jones, Machine Tools Ltd. of  Edgware Road, The Hyde. London. NW9.
Standing just over 81 inches high and with a compact footprint of just 20" x 30", the miller's  25.25" x 9.375" table had three T-slots and 14.5 inches of travel longitudinally and 7.5 inches in and out. 
Powered by a standard-fit, flange-mounted 0.75 h.p. 3-phase motor, the four (later five) spindle speeds were driven by an "A" section V-belt and ran from 325 to 2900 r.p.m. Carried on the end of dovetail ram that could be moved forwards and backwards through six inches of travel, the head could be swivelled through 90° each side of vertical under the precise control of a handwheel set towards the rear of the ra, and working through worm-and-wheel gearing. Fitted with both a worm-and-wheel driven fine feed and a quick-action, lever-operated rack-and-pinion drilling quill, the spindle carried a No. 3 Morse taper nose and ran in an unusually long parallel-bore bronze bush gently tapered on its outside. In order to set the running clearance, the bush was machined longitudinally with a grooves and a slit right through and hence adjustable within its tapered housing. Lubrication was by a special design of wick feed that allowed oil to pass through the bearing and drip into a container - rather along the lines of an early IC engine's "constant-loss" system that ensured only clean oil was used. At the top of the spindle a pair of Hoffman W 13/8 ball thrust races used, these being provided with screw adjustment to take out end float. However, later spindles were considerably modified and fitted with adjustable taper roller bearings at the bottom and an angular contact ball bearing at the top - with threaded collars to adjust the axial preload.
To avoid belt pull upsetting the spindle, the pulley (like those on high-class lathes) ran in its own bearings - one ball and one (expensive-to-replace) parallel roller - and drove the spindle through a long key. For the size of spindle the head was massively built, resulting in a very solid feel and a particularly smooth drive.  Judging by the number surviving both in the UK and overseas, the No. 79 was a popular model and if any reader has a Type 79 miller, or any literature concerning them. the writer would be very interested to hear from you. Pictures continued here

Later-model 5-speed CVA NO. 79 milling and die-sinking machine

The heavily-built head of the CVA miller

Quill rapid-feed handle. The star-shaped wheel on the inside winds the cone-clutch into and out of engagement for drive through the fine-feed control

Components of the fine and rapid-feed mechanism. The cone clutch is the part with a red-painted annulus


Worm-and-wheel head inclination mechanism assembled

Head-rotation mechanism

Main spindle drive pulley, its mounting boss and bearing assembly

In the lower half of the photograph can be seen the main spindle - greased and ready for assembly in the quill housing (upper half)

Early spindle: a long bronze bush at the bottom and, at the top, an angular contact ball bearing with threaded collars to adjust the preload


CVA Milling Machines Page 2

A Sales Sheet is available for this miller    CVA Lathes

CVA No. 79 Milling and
Die-sinking Machine

email: tony@lathes.co.uk
Home   Machine Tool Archive   Machine-tools Sale & Wanted
Machine Tool Manuals   Catalogues   Belts   Books  Accessories