Jakobsen SJ24, Руководство по эксплуатации

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SJ
24
"Grinding in" the magnetic chuck
The surfaces of the chuck have been ground at the factory,
but to insure accuracy, it is neccessary to "grind in" the
chuck on the Grinder with which it is to be used. The
followin rocedure is recommended for a new chuck-=--each
time e c u is remove rom t e mac ine, t e top surface
should again be ground, to insure parallelism between this
surface and the saddle and table ways,
1) carefully clean and degrease
the new chuck.
2) Grind the top (holding) surface of
the chuck first. Place the chuck
on the table and block in place. Do
not clamp the chuck down. Use a
coarse dressed grinding wheel.
3) Dress the grinding wheel.
4) Remove chuck. Clean chuck and table
surface and place chuck on the table
with holding surface down. Block
chuck in place. Grind bottom of
eh uck unti 1 it is flat •
5) Remove chuck and place it in normal
position with holding surface up.
Use table clamps this time.
6) Grind top surface until it is flat.
The final cut should be at
0.004
mm
C.
0002
in) downfeed and
20
mm (. .80 in)
cross feed.
GRINDING INSTRUCTIONS
In surface grinding the choice is between two methods:
Face grinding and edge grinding.
Face grindil'l?means grinding with a large cross feed and
a small cutting depth of about
.000'+" - .0008" co.01-0.02
mm)
and this will in most cases be the most economical way and
will give the best planparallel result.
By edge grinding we recommend to use a large cutting dept,h
up to
.0125"
(0, 3 mm) and manual operated cross feed.
12
Which method to prefer is an individual choice and to a great
extend a matter of experience depending on the material, the
dimension and partly on the grinding wheel used.
Generally speaking it is· recommended to use face grinding
particularly on machine with automatic downfeed and cross
travel.
Edge grinding cannot be advised, when grinding wide surfaces,
as there is a risk for the wheel to be worn out before the
whole width has been ground, giving a non plan-parallel working
piece.