August 2019 11
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Turret Stop
Turret Body
Mat’l: Mild steel, 1 offMarking The Turret Body In Preparation For Number Stamping
Dimensions with * - see text for comment60°(^1) 0.
Number stamp ‘1’ to ‘6’
0.25 adjacent to length screws
0.562 Knurl
0.
Ø2.60
Ø1.25 Ø1.
0.
Ø
Ø2.50
5/16 BSF
(6 places)
on 2.0 PCD
5/16 BSF
(only 2 places
shown)
30°
Turn through 90° to position
turret body for number stamping
Set height gauge to lathe
centreline & scribe a LIGHT
line on turret body periphery to
coincide with tapped hole for
length screw
A
A
Section A-A
2BA
Ø4mm
Use Ø5/32 stainless ball
& Ø3/32 bore x 24g stainless
spring
overcome any small errors in alignment that
may be present.
An adjustable stop fi tted to the stop
block allows for minute adjustments to the
position of the saddle without having to
adjust the individual length screws once
they have been set, thus retaining their
relationship to each other.
The stop block is fi tted with a tee-nut
bar (6.3) which clamps the stop unit to the
mounting bar and also a pair of guide pegs
(6.4) which serve a dual purpose. Although
their main function is to provide guidance
for the stop block in the mounting bar,
they also serve to locate the tee-nut bar
and stop it from rotating, making it easy
to replace the stop unit should you have
removed it for any reason.
The drawing also shows the position
of the stop system in relation to the lathe
bed. If you intend to build this, please check
clearances on your own machine and make
any adjustments to the design that may be
required.
Turret - body (fi g. 2)
Before we start work on the turret, it is
worth seeing what the assembly consists
of. I have included a photograph here of
the fi nish machined turret and some of the
small parts, photo 4, where the bronze
bush has already been fi tted into the turret
body. In the fi nal assembly there will be an
additional fi ve length screws and locking
collars, as well as the two peg keys.
Now let’s get to work, starting with the
turret body and the small parts which go to
make up the turret assembly.
2.1 Turret body
Initially this is a nice easy turning job.
Holding the mild steel blank in a 3-jaw
chuck, fi rstly face off and then turn the rear
boss to 1.25” diameter by 0.5” long, but
don’t drill and bore the central hole yet.
The blank can now be turned around
in the chuck and faced off to the overall
length of 1.5”. At this stage the outside
diameter can be turned to size and the
5 6
Fig.
Drilling the turret body for length screws (posed) Drilling the turret body at the index positions (posed)