Universal Air Tools UT8777AC - Manual (Page 2)

Operating
Select a suitable mounted point that has a free running speed higher
than the maximum running speed marked on the tool. Make sure that
the diameter of the shank exactly matches the diameter of the collet
mounted in the grinder. There are two standard sizes of collet available
for use with this grinder, i.e.
1) - 1/4" dia (0.250ins) (6.35mm)
2) - 6mm (0.236ins)
Never try to force a 1/4" diameter shank into a 6mm collet. Never try to
close a 1/4" diameter collet to secure a 6mm shank. Always match
correctly the shank size to the collet size. If uncertain, have parts
measured by a competent person.
Push the shank as far as possible into the collet and tighten the collet nut
using the spanners provided on the collet nut and output spindle.
The shank of the mounted point may be pulled forward from the
maximum insertion length but always ensure a minimum gripping
length of not less than 10mm - See Figure 2.
Be aware that the allowed running speed of the mounted point is
lowered because of an increase in the length of the shank between the
end of the collet and the body of the mounted point. This distance is
shown in Diagram 2 as "LO" and is called the overhang. The
information with respect to mounted point size, permissible running
speed and reduction in running speed due to an increase in overhang is
available from the supplier of the mounted point.
If the increase in overhang for access reasons takes the permissible
running speed of the mounted point below the free running speed of
the grinder select a smaller diameter mounted point.
The fitting of the mounted point should be done by a trained operator.
When first starting the grinder with a new wheel fitted, the grinder
should not be near other persons and be held in a protected area, i.e.
under a bench and run for a few seconds. This will protect personnel
from possible effects of damage to the mounted point before it was
fitted to the grinder i.e. wheel breakage.
Always use eye protection and wear protective gloves if there are sharp
edges in the work area. The tool and the grinding process can create a
noise level such that the use of ear protectors is advised.
If the grinding process creates a dust then use a suitable breathing
mask.
Check that the material being worked will not cause harmful dust or
fumes. If this is so then special breathing masks may be required.
If the grinder vibrates when first fitting a mounted point or during
operation, remove from service immediately and correct fault before
continuing to use.
Dismantling & Assembly Instructions
Disconnect tool from the air supply.
Using wrenches (26) & (27) grip collet nut (25) and spindle (2) and
unscrew collet nut (25) to remove any fitted grinding wheel and to take
out collet (24). Unscrew clamp nut (1) and pull out the complete motor
assembly from housing (12). Grip rear end plate (10) and tap the non
threaded end of rotor (6) to drive the rotor through rear end plate (10)
and bearing assembly. Remove cylinder (8) noting how the pin (9)
locates in rear end plate (10). Remove 4 off rotor blades (7) from rotor
(6). Grip rotor (6) and unscrew spindle (2). Pull off front end plate (4) and
bearing assembly. Remove collar (5) and tap out bearing (3) from end
plate (4) and bearing (11) from end plate (10). Unscrew air inlet (22)
and remove O-ring (17) and exhaust sleeve (16). Pull out throttle spring
(21) and throttle value (20). Drive out spring pin (15) and remove valve
stem (13) and trigger button (14).
Reassembly
Clean all items and examine for damage and wear. Replace any parts
with parts obtained from the manufacturer or an approved supplier.
Coat all parts with a pneumatic tool lubricating oil and assemble in the
reverse order.
slowly for a few seconds to allow air to circulate the oil. If tool is used
frequently lubricate on daily basis and if tool starts to slow or lose power.
It is recommended that the air pressure at the tool whilst the tool is
running is 90 p.s.i./6.3 bar. The tool can run at lower and higher
pressures with the maximum permitted working air pressure of 100
p.s.i./7.0 bar.
Page No 2
Safety Rules When Using A Die Grinder
1) Read all the instructions before using this tool. All operators must be
fully trained in its use and aware of these safety rules.
2) Always select suitable abrasive to use with this tool - see Operating
Instructions.
3) Always shut off the air supply to the grinder and depress the lever to
exhaust air from the feed hose before fitting, adjusting or removing the
mounted point.
4) Always adopt a firm footing and/or position before using the grinder.
5) Use only correct spare parts.
6) Check hose and fittings regularly for wear. Do not carry the tool by its
hose.
7) Do not remove and never tie down the safety lever.
8) Never exceed the maximum air pressure and check the free running
speed frequently. Have air regulator fully open when making speed
checks.
9) Use safety equipment as recommended.
10) Take care against entanglement of moving parts of the tool with
clothing, ties, hair, cleaning rags, etc.
11) Use only compressed air at the recommended pressure.
12) Do not attempt to fit any other attachment than those
recommended - see "Foreseen Use of Tool".
13) If the tool appears to malfunction, remove from use immediately,
and arrange for service and repair.
D = diameter of mounted point
T = length of mounted point
Lo = overhang
S = diameter of shank
Lg = gripping length
Do not apply excessive pressure as this will reduce the cutting
efficiency and can bend the shank of the mounted point causing
vibration and the possibility of breakage. Apply light loads to allow the
wheel to cut.
Handle the grinder with care. If the grinder is dropped, carefully check
the mounted point for damage, i.e. cracks, chipping and start for the
first time as for fitting a new wheel i.e. under a bench.
Never exceed the maximum air pressure. If there is this possibility
always use this grinder with a pressure reducing valve fitted in the
supply line. Your supplier will advise of suitable equipment.