User manual

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3. Move the tailstock with drill chuck and centring drill up to
the
face of the work piece.
4.
Switch on the machine and drill centreboreusing the sleeve
feed.
5.
Replace the drill chuck with the rotating centre1(Fig. 17).
6. Insert the centreinthe centreboreand clamp the tailstock
3securely.
7. Advance the sleeve 2until all play is eliminated.
8. Securethe sleeve using aset screw 4.
Fitting change gears for thread cutting
Note:
The PROXXON Lathe PD 250/E can be used to cut metric
threads with apitch of: 0.5 (M3), 0.625, 0.7 (M4), 0.75,
0.8 (M5), 1.0 (M6), 1.25 (M8), and 1.5 (M10).
The PD 250/E is supplied with installed gear arm and the
change gear combination for the automatic feed of 0.05
mm/revolution. It is only necessary to replace the change gears
installed on the gear arm for thread cutting.
1. Release the clamp screw 1(Fig. 18) and tilt the gear arm 2
slightly upwards to remove the toothed belt 4.
2. Remove the fastening screws 3and 5fromthe normal gears
for the automatic feed.
Note:
The number of teeth is imprinted on all change gears.
For example, if cutting athread with apitch of 1.0 mm, the table
on the drive gearbox will show the following data:
W15-gear on the main spindle with 15 teeth. This gear is
already installed on the shaft and must not be replaced.
Z
1
15 -Z
2
20 -Intermediate gear for the toothed belt of the
main
spindle with 15 teeth and permanently linked gear for the
leadscrew with 20 teeth.
L20 -leadscrew gear with 20 teeth.
3.
Fasten the change gear "Z
1
-Z
2
"w
ith 15/20 teeth (Fig. 19) to
the
gear arm 3using the screw 2, pulley,reduction sleeve
and nut.
Note:
Do not yet tighten the fastening screw nut 2(off-centreadjust-
ment
must still be possible).
The change gear "Z
1
-Z
2
"runs freely between pulley and sleeve.
The washer prevents the toothed belt from becoming detached
from the gear "Z
1
".
4.
Release the set screw 1, remove the change gear "L40" and
replace with the change gear "L20".
Note:
The grain of the leadscrew change "L" must always point to the
lathe chuck.
The set screw 1must be clamped onto the flattened part of the
shaft.
Important
To ensurethat thereissufficient play between the change
gears, always insert astrip of newspaper between the teeth
when pushing the change gears together.The thickness of the
newspaper should correspond to the required tooth play.
5. Push the axle of the change gear "Z
1
-Z
2
"onto the arm so
that it contacts the leadscrew gear "L" and then tighten the
fastening screw nut 2.
6. Position the short toothed belt for the connection between
the gears "W" and "Z
1
"onthe main spindles.
7. Push the gear arm 3downwards and tighten the clamp
screw 4.
Thread cutting with the turning tool
Note:
For the following operations, the work piece must be machined
completely and have the correct thread outer diameter.
It is advisable to work out achamfer at the beginning of the
thread. The thread turning tool must be clamped at an angle of
90° exactly.
1. Clamp the work piece.
2. Switch offthe automatic feed and set the turning tool to the
starting position.
Important
Use the lowest speed when cutting threads and proceed with
utmost caution.
3. Press button 2(Fig. 20) to switch on the machine (clockwise
rotation).
4. Advance the turning tool on the cross-slide 1and engage
feed 3.
5. Switch offthe machine when the required thread length has
been reached 2.