Sealey SM27 - Manual (Page 4)

4.4. Tool Post
up to four tools can be mounted on the tool post. the post can be rotated, in 90° steps,
by slackening the locking handle (fig.3.1), and slightly lifting the post. Always ensure
that the locking handle and tool clamp screws (fig.3.2) are tight before starting to cut.
the tool post is mounted on the compound slide, which in turn is mounted on the cross
slide. the compound slide can be rotated ±60° on the cross slide to permit bevel and
taper cutting. to rotate the compound slide, loosen the two clamp nuts (fig.3.4) and
rotate the slide to the required angle. tighten the clamp nuts.
the cross slide can be locked in position along the bed by the locking lever (fig.1.8).
4.5. Chuck
the chuck is supplied with internal jaws fitted and a set of external jaws. to remove
and fit jaws proceed as follows:
using the chuck key, fully wind out the fitted jaws, at which point they can be pulled
from the chuck.
the thread segments on the jaws are staggered and therefore the jaws are numbered
1 to 3 (on the inner end of the left location groove) and must be fitted in this sequence,
in an anticlockwise direction (facing the chuck).
turn the chuck key anticlockwise while watching the chuck thread in one of the jaw
slots. When the end of the thread has just cleared the slot, stop turning the key and
insert jaw 1 into this slot. Insert the other two jaws in the other slots in sequence.
Hold them under light pressure whilst turning the key clockwise until they are picked
up by the thread and start to move inwards.
check that the three jaws come together correctly at the centre of the chuck. If not, repeat the procedure.
4.6. Speed
the headstock spindle is belt driven and the speed is determined by the belt arrangement. to change the speed proceed as follows:
4.6.1. open the belt cover (fig.1.1).
4.6.2. Slacken the motor adjuster nuts and the centre pulley nut (fig.4.A & B).
4.6.3. Position the belt(s) to give the required lathe speed, see fig.5.
4.6.4. check that the weight of the motor is tensioning the belt(s) and then tighten the motor adjuster nuts and the centre pulley nut.

WARNING! Before starting the lathe always confirm that nothing will contact the chuck by rotating the chuck by hand with the
tool post as far to the left as it will be during the turning operation. Make sure that the chuck guard is in place, as shown in
fig.1.2. The lathe will not operate with the chuck guard raised.
4.7. Turning
4.7.1. Mount the cutting tool in the tool post such that the tip of the tool is level with, or just below, the lathe centre line. check this by aligning
the tool tip with the point of the tailstock. The tool tip must not be above the centre line. the height of the tool tip may be adjusted
by shimming or grinding the tool.
4.7.2. Mount the workpiece in the chuck or on the face plate (optional, see Accessories Section) and, if necessary, support the other end
with the tailstock. A fixed steady and a moving steady are also available, see Accessories Section.
4.7.3. Set the speed and forward/reverse switch to suit the job. the leadscrew lever (fig.2.A) should be at position o.
4.8. Turning with auto feed
4.8.1. Proceed as in 4.7. but in 4.7.3. set the leadscrew lever (fig. 2.A) to I or II. With the gear set as supplied, position I will feed the tool at
0.075mm/rev and position II at 0.15mm/rev (see Auto feed for turning, fig.7). ensure that the cross slide lock (fig.1.8) is not applied.
4.8.2. Position the tool just to the right of the end of the workpiece and start the lathe.
4.8.3. turn the auto feed lever (fig.2.B) anticlockwise to engage the leadscrew. the tool will now move to the left and begin cutting.
4.8.4. Be ready to disengage the leadscrew when the tool reaches the end of the cut. DO NOT allow the tool to over-travel and come into
contact with the chuck.
Always be prepared to hit the stop button if the leadscrew cannot be disengaged.
4.9. Screw cutting
Similar to turning with auto feed except that the feed rate is very much faster, demanding increased care from the operator.
4.9.1. Select the required leadscrew gear train from the charts (fig.7).
4.9.2. open the headstock end cover (fig.1.1).
4.9.3. remove the gear retaining circlips and nut (fig.6.1, 2 & 3) and slacken the adjuster screw (fig.6.4).
4.9.4. replace the existing gears with those required, in the positions shown in fig.8.
4.9.5. Adjust gears B and c, so that the train meshes with minimum backlash but without being tight.
4.9.6. tighten adjuster screw (fig.6.4) and refit the end cover. DO NOT operate the lathe with the end cover open.
fig.3
Spindle
Speed rpm
A 160
B 250
C 400
D 630
E 1000
F 1600
fig.5
fig.4
fig.6
Original Language Version
SM27.V2 Issue: 1 - 06/02/12