Three Jaw Universal Chuck; Taper Turning With Tailstock; Turning Between Centres; Taper Turning With Top Slide - Promac BD-8BM Mode D'emploi

Fig 12
Adjust gears to mesh with upper and
lower gear.
Placing ordinary paper in between
gears helps to adjust for correct gear
spacing (... remove the paper
afterwards!).
Close and lock the pulley cover.
Note: Inch threads 36, 44 and 56TPI
can be cut with optionally available
change gears (see parts list)

7.2 Turning between centres

Mount the work piece fitted with the
drive dog between centres.
The driver is driven by the face plate
(Fig 13).
Fig 13
Lubricate the tailstock centre with
grease to prevent tip from overheating.

7.3 Taper turning with tailstock

The work piece must be held between
centres and driven by the face plate
and drive dog.
Fig 14
To offset the tailstock, loosen the
locking screws (Z, Fig 14) and use
screws (Y) to adjust.
After taper turning, the tailstock must
be returned to its original position.
Turn a test piece and adjust until the
machine turns a perfect cylinder.

7.4 Taper turning with top slide

By angling the top slide, tapers may
be turned.
Loosen two hex socket bolts (A, Fig
15) and rotate the top slide according
to the graduated scale.
6
Fig 15

7.5 Three jaw universal chuck

With this universal chuck, cylindrical,
triangular and hexagonal stock may be
clamped (Fig 16).
Fig 16
To hold big diameter stock, a set of
3 OD chuck jaws is supplied.
The jaws always need to be inserted
to the chuck in the correct order.
Use Molykote Paste G (or adequate
grease) to lubricate the jaws.
7.6 Four jaw independent chuck
(optional)
This chuck has four independently
adjustable chuck jaws (Fig 17).
These permit the holding of square
and asymmetrical pieces and enable
the accurate concentric set-up of
cylindrical pieces.
Fig 17
7.7 Live centre (optional)
The live centre is mounted in ball
bearings.
Its use is highly recommended for
speeds above 500 RPM.