Proxxon UT 400 Bedienungsanleitung Seite 7

8 This example shows how to approach this in
practice
Loosen the knurled screw on the crank and move the pin to
the diameter of the 42/27 index plate which must be used:
The 27 bolt circle here is the inner of the two. Retighten
knurled screw.
1. Find the required division in the table and select the ap-
propriate index plate.
2. If necessary, insert the selected index plate. See the
chapter: "Changing the index plates"
3. Clamp work piece and move to 0-position (initial positi-
on). Attention: Make sure that the fl ange can turn freely
and is not jammed.
4. Engage the crank pin in a hole on the appropriate bolt
circle.
5. Clamp fl ange, then perform fi rst machining operation.
6. Loosen the clamp.
7. Turn the (upper) sector limiter (1, Fig.11) clockwise until
it strikes the still engaged crank pin 3.
8. Turn the lower sector limiter 2 clockwise by the number
of additional holes required (the table value from co-
lumn "d"!) The upper sector limiter remains in contact
with the engaged crank pin.
9. Disengage the crank pin and turn the crank. The po-
sition of sector limiter A serves as a marking for the
original crank position: with its help, the full revolutions
can be counted.
10. The sector limiter 2 marks the spacing according to the
additionally required holes: these are now "enclosed"
between the two sector limiters: so we turn the crank
beyond the full revolutions (marked by sector limiter 1)
until the limit stop at sector limiter 2 and lock it there.
This completes the required number of full revolutions
with the crank, plus the additional holes required.
11. Clamp fl ange again and carry out machining.
12. Loosen fl ange after machining
13. Turn the "scissors" formed by the sector limiters so that
sector limiter 1 strikes the crank again. Sector limiter 2
rotates along automatically. Make sure that the distance
between the two (i.e. the angle of the "scissors") is not
changed during work! This distance is "carried along"
during the entire work.
14. Pull the crank pin from the latch, perform two full re-
volutions (please refer to sector limiter 1) and continue
turning until the limit stop at sector limiter 2.
15. Clamp fl ange again and carry out machining.
16. Repeat the described steps until all required machining
operations are performed.
9 The index plates are changed as follows (see
Fig. 12)
1. Release knurled screw 1 and remove crank 2. Pull off
spacer 3.
2. The unit with the sector limits is also removed, see Fig. 13.
3. Remove the index plate after loosening the two Phillips
screws (1, Fig. 14), fi t new ones and secure with the
two screws.
10 Re-inserting the worm gear together with
the crank
It is basically possible to reposition the worm gear together
with the crank: depending on the assembly situation or
task, it is possible to insert the entire assembly unit into the
insertion opening from two sides of the base body.
Loosen the headless screw 1 according to Fig. 15. Pull out
the entire worm gear (with guide sleeve, index plate and
crank).
Attention: Now take a close look at the worm gear with the
guide sleeve (Fig. 16). You can see that the sleeve has been
drilled eccentrically.
This can best be seen by the material thickness of the
sleeve on the worm side. If you now insert the entire unit
into the required opening of the base body of the dividing
head, make sure that the strong material side is at the bot-
tom. Reason: the worm is positioned slightly upwards, but
this makes it easier to "intermesh" with the teeth on the
rotary fl ange (the feed receiver of the UT 400) when insert-
ing it into the opening.
Avoiding "play" between crank and main spindle is impor-
tant for proper working. After insertion, a nearly backlash-
free connection is established by turning the entire unit and
pressing the worm downwards onto the gear wheel. Turn by
approx. 45 to 60 degrees until you feel resistance. Now turn
the entire unit back by 1 to 2 degrees (in the interest of a
"smooth-running" crank) and then fi x with a headless screw.
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