Universal Air Tools UT8738 User Manual

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Includes - Foreseen Use, Work Stations, Putting Into Service, Operating,

Operator Instructions Important

Read these instructions carefully before installing, operating,
servicing or repairing this tool. Keep these instructions in a safe

Test Method

Tested in accordance with Pneurop

test code PN8NTC1 and ISO Standard 3744

Vibration Level

Test Method

Tested in accordance with ISO

Less than 2.5

Dismantling, Assembly and Safety Rules

accessible place.

Manufacturer/Supplier Product Type

Universal Air Tool Company Limited

Extended Die Grinder

Unit 8
Lane End Industrial Park
High Wycombe
Bucks

Model No/Nos Serial No

UT8738

HP14 3BY

[phone] [phone]

Product Nett Weight

3.3

1.5 3/8 10 30 10

Recommended Working
Recommended Minimum
Maximum

Use - Safety Glasses
Use - Safety Gloves
Use - Safety Boots
Use - Breathing Masks
Use - Ear Protectors

lbs
Kg

Air Pressure

Personal Safety Equipment

Recommended Use Of

Balancer Or Support

No

bar

6.3
n/a

7.0

bar
bar

90

n/a

100

Yes
Yes

Yes
Yes

Recommended Hose Bore

Size - Minimum

Ins M/M Ft M

Noise Level

PSI
PSI
PSI

Sound Pressure Level 82.0 dB(A)

standard 8662/1 & 8662/13

RPM

18,000

Cycles Per Min

Recommended Max.

Hose Length

Metres / Sec²

Foreseen Use Of The Tool

This die grinder is primarily designed for use with bonded abrasive
mounted point grinding wheels. It may also be used with steel rotary
files and carbide burrs provided their speed rating matches the speed of
the grinder.
This tool should not be fitted with cutting off wheels, saw blades, drill
bits, etc. If there is any doubt about the correct use of this product
contact your supplier for advice.
Also make sure that the shank size of the attachment to be driven
matches with the collet size fitted in the grinder and that the maximum
allowed running speed of the attachment exceeds that marked on the
grinder.
There are special rules governing the use of bonded abrasive mounted
point grinding wheels - for details see section "Operating".

Work Stations

The tool should only be used
as a handheld hand
operated tool. It is always
recommended that the tool
is used when standing on the
solid floor. It can be used in
other positions but before
any such use, the operator
must be in a secure position
having a firm grip and footing
and be aware of the extra
safety precautions that must
be observed when using
Grinding Machines.

Putting Into Service

Air Supply

Use a clean lubricated air supply that will give a measured air pressure
at the tool of 90 p.s.i./6.3 bar when the tool is running with the
lever/trigger fully depressed. Use recommended hose size and length.
It is recommended that the tool is connected to the air supply as shown
in figure 1. Do not connect the tool to the air line system without
incorporating an easy to reach and operate air shut off valve. The air
supply should be lubricated. It is strongly recommended that an air filter,
regulator, lubricator (FRL) is used as shown in Figure 1 as this will supply
clean, lubricated air at the correct pressure to the tool. Details of such
equipment can be obtained from your supplier. If such equipment is not
used then the tool should be lubricated by shutting off the air supply to
the tool, depressurising the line by pressing the lever/trigger on the tool.
Disconnect the air line and pour into the intake bushing a teaspoonful
(5ml) of a suitable pneumatic motor lubricating oil preferably

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incorporating a rust inhibitor. Reconnect tool to air supply and run tool
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.

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 five standard sizes of collet available
for use with this grinder, i.e.

1) - 1/4" Dia (0.250ins) (6.35mm)

2) - 6mm (0.236ins)

3) - 1/8" (0.125ins) (3.175mm)

4) - 3mm (0.118ins)

5) - 8mm (0.315ins)
Never try to force a 1/4" diameter shank into a 6mm collet or a 1/8"
diameter shank into a 3mm collet. Never try to close a 1/4" diameter
collet to secure a 6mm shank or a 1/8" diameter collet to secure a
3mm diameter 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.
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.

Figure 2. Gripping length of collet and chuck

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.

Dismantling & Assembly Instructions

Disconnect tool from air supply.
Grip housing (1) with comfort grip (35) in a vise fitted with soft jaws. With
a snap ring plier, remove the snap ring (38). By using an adjustable
wrench, unscrew the air hose assembly (39), swivel air inlet (36) and air
inlet (13) then separate o-ring (3), connecting ring (37), muffler (14) and
o-ring (3). With a wide bladed screw driver unscrew valve plug (10) and
remove o-ring (9), (8), air regulator (7), spring (6), throttle pin (5), o-rings
(4). Do not remove throttle valve bushing (2) with o-rings (3) unless a
replacement is required.
Use a proper steel bar, tap out pin (12) and remove throttle lever (11)
from housing (1).
Release housing (1) with comfort grip (35) from vise, slide off comfort
grip (35) from housing (1) then return housing (1) to vise.
With an adjustable wrench, unscrew spindle housing (27) from housing
(1). Pull out (28) to (33) from spindle housing (27). Unscrew collet nut
(33) and pull out collet (32). Unscrew chuck spindle (31), take out
retaining ring (28) and remove ball bearings (29) from extension spindle
(30). Remove spindle (25) and housing cap (26).
Pull out the motor assembly from housing (1). Grip the front end plate

(23), to avoid the splines of rotor (18) from
damage, use a rubber hammer, slightly tap the
splinted end of the rotor (18) through the front
end plate (23) and ball bearing (24) assembly.
Take off cylinder (21) and remove spacer (20)

D = diameter of mounted point
T = length of mounted point
Lo = overhang
S = diameter of shank
Lg = gripping length

and rotor blades (19). With a suitable punch,
tap the rear end of rotor (18) slightly to

separate rotor (18) from rear end plate (16).
Then press out ball bearing (24) from front end plate (23) and ball
bearing (15) from rear end plate (16). Do not remove steel balls (22)
and pin (17) from front end plate (23) and rear end plate (16) unless
replacements are required.

Reassemble

Clean all parts and examine for wear, replacing any worn or
damaged parts. Use only replacement parts obtained from
the manufacturer or an authorized distributor. Lightly coat all
parts with a suitable pneumatic tool lubricating oil and
assemble tool in reverse order.

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.

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