email: tony@lathes.co.uk
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GRIGG Lathe - England

Once long-forgotten, in recent years a few of the lightly-built Grigg lathes have come to light.  Manufactured by the Grigg Motor and Engineering Company Ltd. of Twickenham, Middlesex, England, it had a leadscrew running down the centre line of the bed and a single swivelling tool slide - both features being along the same lines as the early Drummond 31/2" flat bed. The design appears to date from early years of the 29th century - with production most likely to have been in the first decade though possibly continuing after WW!. Intended for either bench mounting or fitted to a self-contained, treadle and flywheel stand with a cast-iron chip tray, the Gigg was of almost miniature proportions - just 24-inches long and with a centre height of around 3 inches and a capacity between centres of 12 inches. A gap in the bed was provided and power sliding was by changewheels, though with no backgear fitted to reduce the spindle speed, trying to use the drive for screwcutting would have been difficult. 
Equipped with plain bronze bearings supported on the slenderest of posts, the headstock was located on the flat-topped, 60-degree dovetailed-edged bed by a central tennon and retained in place by a single bolt though its centre. The drive pulley, replaced in the pictures below by a modern V-type, would originally have been of the type that mounted a 3-step, round leather "gut" drive. Unusually, the section of bed beneath the headstock was longer than necessary, possibly to allow the changewheel bracket to be swung out of the way and the headstock (or  "loose head" as it would have been known at the time) slid back to obtain a little more distance between centres.
Of considerable length for such a small machine, the saddle carried two traverse T-slots, this feature allowing it be used as small boring table. However, the very wide and somewhat cumbersome tool slide, bereft of a micrometer dial, reflected a contemporary weakness: it was carried on a bar that fitted into a boss cast on the front edge of the saddle. Denied proper support, it would thus have been the root cause of the tool chatter almost inevitable - on other than light cuts - with this inferior design.
Besides its slender construction, the tailstock too had an unfortunate drawback, its front edge was vertical and, when drawn up against the face of the saddle, its No. 1 Morse taper barrel would have had insufficient long reach to contact the headstock centre. The barrel was inefficiently locked, as on so many other contemporary, cheaper lathes, by a long slot in the casting nipped up by a pinch bolt.
Despite the inadequacies evident in the design (all contemporary weaknesses that took over three decades to gradually eliminate from small lathes) the Grigg exhibited good detailing and thoughtful touches with decently-large changewheel mounting studs (and easy-to-grip knurled retaining nuts), pin-hole locking rings to set the headstock spindle end float, good-sized handwheels on the leadscrew and tailstock and a large, flat-topped tool slide that would have allowed the owner the chance to adapt it for any number of ingenious purposes. .


Evident in this picture are the slender headstock with its tennon fitting  and single retaining bolt, cast-iron chip tray belt cut-out and neat detailing on changewheel bracket and headstock spindle end. The headstock pulley would originally have been a 3-step for drive by a round leather rope

The considerable length of the T-slotted saddle and wide cross slide are clearly evident



The mounting of the tool slide betrayed a contemporary weakness - it was carried on a bar that fitted into a boss cast on the front edge of the saddle. Denied proper support it would thus have been the root cause of  tool chatter that was almost inevitable (on other than light cuts) with this design. It is likely that the screw adjustment for height has been added by an owner.



email: tony@lathes.co.uk
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GRIGG Lathe - England