The writer would like to acquire a parts list for the
later 1A machines - and any early advertising literature.
Left-hand side of the Power-feed head on the very similar English-made "Elliot Mini Jig Borer". In this case the power feed was in both directions, unlike the pre-1964 Linley installation which worked on down-feed only.
Right-hand side of the Power-feed head on the Elliot Mini Jig Borer. The head was fitted with a very useful Direct-reading Micrometer Depth Gauge - its graduated square bar can seen passing through a boss on the side of the casting. It's method of operation was simple: to machine to a depth of 1.167 inches the cutting tool was set in contact with the work and the square bar moved until it was at any even line. The stop screw was then lowered until it made contact with the top of the bar - and locked. The dial was set at zero, its setting locked, and the bar lowered 11 divisions. The cut could now be made until the stop screw was met; this was then released and the remaining 0.067" fed in using the dial.
The saddle assembly, micrometer dials and rulers on the Elliott all differed in detail - even in comparison with the original Linley Mk. 1
Because the machine was in three sections - base cabinet, knee section and main column - it was possible to introduce a distance piece between the two upper parts and so increase the spindle to table distance by around 4 inches.
The original table had narrow ways and a lock that acted directly on the gib strip, so moving the table slightly when it was tightened - not a situation that is welcome in the construction of a jig borer. The picture below shows how the makers tackled the problem with slightly wider ways and a modified lock which secured the table without moving it.
At some point during the production of the original machine, the table ways were made slightly wider and fitted with what the makers called a "flexible-blade, non-influencing type table lock" the function of which was to "prevent longitudinal movement whilst absorbing any lateral pressure from the lock screws." The table was also fitted with finely-engraved rulers.
An early Mk. 1 head without power down-feed.
Beautifully restored by David Harding in the USA, this late model Linley 1A has both the desirable variable-speed spindle drive and the massive power down-feed unit.
Inside the mechanical variable-speed drive unit showing the 1-inch wide transmission belt between the expanding and contracting pulleys.
Although missing its original belt guard and motor mount this very early Linley appears to be otherwise complete
A rebuilt Linley complete with that essential jig borer accessory a micrometer boring head - in this case adapted from a Bridgeport unit