Fein Grit GX75 Series User manual

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
GX 75 / GX 75 2H

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
GX 75 / GX 75 2H
Specifications
Type GX 75 GX 75 2H
Reference number 7 901 01 00 403 7 901 02 00 403
No - load speed (U/min) 3000 1500 / 3000
Power input (kW) 3,0 1,5 / 2,0
Voltage (Volt) 3 x 400 3 x 400
Frequency (Hz) 50 50
Grinding - belt speed (m/s) 30 15 / 30
Weight (kg) 75 75
Class of protection I I
Belt dimension (width/lenght in mm) 75 x 2000 75 x 2000

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
Safety precautions
Before you start rerpairing and at least after having finished repair ( especially motor or switch ) it´s important
to test the turning direction of the motor without grinding belt mounted. If the turning direction is wrong
(and working with grinding belt mounted) it can cause accidents and damages of the belt grinder .
Furthermore you can´t adjust a belt grinder correctly if the running direction is wrong!
Correct
turning direction

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
Test instructions referring to VDE 701 / part 1
Grit –belt grinders are basicly placed in protection class 1.
After repairing or changing of motor, switch or cable etc. each belt grinder must be
electrical tested referring to VDE 701/part 1 as shown in the list below.
1. protective earth
conductor test 1. Activate Measuring points: machine housing against PE on the plug
Open circuit voltage on the measuring device: 4 V - 24 V, AC or DC
Measurment current: min. 0.2 A
Testing time: 3 sec
PE resistance: max. 0.3 Ohm with 5 m long mains power cable
2. Insulation
resistance
measurement
1. Activate
2. Connect L1 and N to plug
3. Motor switch "ON"
Measuring points: machine housing against L1, L2, L3
Testing time: 3 sec
Testing voltage: 500 V DC
Insulation resistance: min 2.0 M Ohm
3. High voltage test 1. Activate
2. Connect L1 and N to plug
3. Main switch "ON"
Measuring points: Machine against L1, L2, L3
Testing time: 3 sec
Testing voltage: 1000 V AC
Trip circuit: 5mA > overload relay must not respond

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
Table of contents
1. Drive wheel
1.1. Drive wheel - dismounting
1.2. Drive wheel - mounting
1.3. Adjusting of grinding belt
2. Contact wheel
2.1. Contact wheel - dismounting
3. Gas spring
3.1. Gas spring - dismounting
3.2. Gas spring - mounting
4. Motor
4.1. Motor - dismounting
5. Switch box
5.1. Connection diagrams
5.2. Switch box - dismounting
6. Most common spare parts

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
1. Drive wheel
In case of growing noise level or vibrations the Grit Machine must be stopped to
check the drive wheel. A new drive wheel is always crowned and balanced. During the grinding process
a large volume of grinding dust is produced. This dust can be easily fastened at the inner surfaces
(look at picture) of the drive wheel and is causing an unbalance in the drive wheel.
Another reason for vibrations can be a broken hub on the inner site of the drive wheel.
It can be caused by a failure in the aluminium casting process of the drive wheel.
In case of a heavy contamination the drive wheel
has to be dismounted and checked from both sides.
If necessary the drive wheel has to be changed.
A broken hub can‘t be detected by opening the machine housing.
If there are strong vibrations without heavy dust contamination the
drive wheel has to be dismounted.
Is there a broken hub the drive wheel has to be changed.

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
1. Drive wheel
Drive wheel - Aluminium
Standard on GX - Machines
Drive wheel - Polyurethane
Can also be used on GX - Machines,
longer endurance as aluminum

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
1. Drive wheel
Normal wear New condition
„crowned“ surface
If the grinding belt gets difficult to adjust or steer, you must check the surface of the drive wheel.
On a new drive wheel the surface is crowned (left picture). If crowning worn out or if irregular wearing
of the surface has occurred the drive wheel must be replaced. Depending on working intensity
the endurance is very different. It concerns drive wheels made of aluminiumn as well as drive wheels
with polyurethane.
The wearing is perceptible when the grinding belt starts moving and it‘s impossible to steer!

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
1. Drive wheel
The pictures on the left shows an irregular wear out on
an unbalanced driving wheel because of a
heavy grinding contamination.

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
1.1. Drive wheel - dismounting
1. Open the side door and take it off.
2. Loosen fixing screw/handle of the cover for surface grinding table.
3. Cover for surface grinding table must be taken off.
Tool :
Allen key 6 mm

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
1.1. Drive wheel - dismounting
1. Loosen the fixing screw of the drive wheel and take it off.
2. Fasten the drive wheel puller onto the drive wheel and screw on the big
hexagon head screw using a fork wrench (M24).
3. Take off the drive wheel.
Tools :
Allen key 8 mm
Fork wrench 24 mm
Drive wheel puller 6 99 02 410 000

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
1.2. Drive wheel - mounting
1. Before the drive wheel is mounted, the shaft must be lubricated.
2. If it‘s difficult to put the driving wheel on by hand, a rubber mallet
can be used to move on the driving wheel with slightly hammer hits.
Tools :
Rubber mallet

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
1.3. Adjusting of belt tracking

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
1.3. Adjusting of belt tracking
In the manual Original

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
2. Contact wheel
In case of a noisy and vibrating Grit machine it‘s also important to check the status of the contact wheel.
It is also important to check that the bearings are running noiselees and without any resistance.
Vibrations in the contact wheel occur if grinding takes place at the same spot, if the
polyurethane lining has come off , if pieces of polyurethane are broken off partly or if the polyurethane has
been burnt by red hot dust particles in a full spark box.
If the contact wheel runs in a condition as mentioned before, the bearings will fail too.Also the dirt
that will be fastened on both sides of the contact wheel during the grinding process can give an
unbalance and can damage the bearings if not regularly cleaned.

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
2. Contact wheel
In case of changing the ball bearings it‘s possible to order a service kit that contents
the two bearings , different locking rings, distance rings, screws and shaft.
Order no.: 3 90 00 001 45 9

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
2. Contact wheel
The contact wheel bracket has been set up from the factory. If it‘s impossible to adjust the belt,
even after replacement of drive wheel, contact wheel or gas spring, it can be necessary to adjust
the setting of the contact wheel bracket. However this should only be done as the last possibility
after checking all other settings: belt tension, drive wheel, contact wheel and belt adjustment.
- Loosen nuts
- Contact wheel bracket
can be moved in 2 directions
(forward or backward) .
A rubber mallet can be very
usefull.
Last possibility - Read text underneath

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
2.1. Contact wheel - dismounting
1. Loosen handle ( yellow arrow )
2. Take off spark box with work piece support
3. Take off the eye protection shield .

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
2.1. Contact wheel –dismounting
1. Loosen the screw M10 (allen key 8mm)
2. Loosen the screw M8 (allen key 5 mm)
3. Take off the contact wheel
Tools :
Allen key 8 mm
Allen key 5 mm

GRIT by FEIN
Alle Rechte bei FEIN, insbesondere für den Fall der Schutzrechtanmeldung.
Jede Verfügungsbefugnis wie Kopieren und Weitergabe liegt bei FEIN. Sahre / MVK 04 / 2009
Hedenstedt / Grit
3. Gas spring
The gas spring is mainly responsible for the optimal belt tension.A correct belt tension is very important
for working with the machine without any problems.
If belt tension is to weak the belt will slip on the drive wheel each time the machine is started and
switched off even if workpiece is pressed against the belt. This will cause a wear out of the crowning
on the drive wheel and creating an unbalance.After a while it will be impossible to hold the belt in the
required tracking position.
Reduced functioning of a gas spring can be caused by contamination of grinding dust
and therefore it is very important clean up the machine regularly ( optimal : every day )
Only an optimal working gas spring guarantees the correct belt tension and the belt change can be done
without any problems.
Since beginning of 2008 only gas springs from the german company „SUSPA“ are used.