Trelawny MHS11 Troubleshooting guide

MHS11 MULTI-HEADED SCABBLER
OPERATION & MAINTENANCE

OPERATION
General Information
Thank you for your purchase of the Multi-
headed Scabbler.
Before operating the Multi-headed Scabbler,
this manual must be read and understood by
the operator, if in any doubt ask your
supervisor before using this equipment.
Failure to follow these instructions could result
in damage to the Scaler and/or personal
injury.
Trelawny SPT Ltd disclaims all responsibility
for damage to persons or objects arising as a
consequence of incorrect handling of the tool,
failure to inspect the tool prior to starting work
for damage or other faults that may influence
the operation or safe working of the tool, or
failure to follow the safety regulations or
applicable to the job site.
The tool is primarily designed for concrete
reduction, and the removal of laitance from
concrete floors, but may also be used for the
removal of paint or epoxy floor coatings, it can
be used both indoors and out.
This machine must not be used in a fixture.
Note:
Bush Hammer style headed pistons are best
suited to concrete reduction and for laitance
removal; these may reduce the likelihood of
damage to the aggregate, ensuring that a
stronger bond is created with the next fill or
finish layer.
Cruciform headed pistons are suited to the
reduction of concrete or where a smoother
finish is required, these will reduce the
aggregate as well as the concrete surface
leaving a relatively flat surface, these are also
suitable for the removal of paint and epoxy
coatings.
Operators should be familiar with the data
given in the specification section.
Please keep these instructions in a safe and
accessible place.
This tool must not be used in potentially
explosive atmospheres.
Where a vacuum shroud assembly is supplied
separately, see the instructions under
“Servicing” for fitting.
Manual Handling
The complete tool weighs approximately 70kg
(155lbs).
Where possible use a hoist with correctly
rated lifting equipment to connect to the
supplied lifting eyebolt fitted on the top of the
MHS11 Scabbler.
Ensure that the eyebolt is screwed down to its
shoulder and has been tightened using a bar
no longer than 150mm (6.00”).
Always ensure the handle is locked and
secure during any handling operation.
Always apply local health and safety
regulations with regard to manual handling.
Safety Precautions
Do wear Personal Protective Equipment
including safety goggles, footwear, ear
defenders and gloves. In some environments
it will be necessary to wear facemasks or
breathing apparatus.
Do be aware that this tool is not electrically
insulated.
Do ensure that this tool is lubricated daily.
Do be aware that this tool can create dust and
flying debris.
Do be aware of others working around you.
Do keep hands and clothing away from
moving parts.
Do store this tool in a secure and dry
environment.
Always observe safe working practices
and local safety regulations at all times.
Do not allow the tool to run unattended.
Do not allow the tool to run continuously
whilst not in contact with the surface being
prepared.
Do not modify this tool in any way, as this will
invalidate the warranty and could lead to
serious injury.
Do not use this tool in potentially explosive
environments.
Do not drag this tool by the air hose.
Do not use petrol (gasoline), thinners or any
other high flash point solvent to clean the tool.
Please note: Unrestrained hoses can whip if
they become detached.
Ensure that the work place is well ventilated.
Avoid operating engine-powered compressors
in an enclosed area, since engine exhaust
gases are poisonous.
Recommended
lubricants
Oil the tool daily before use. Put a liberal
quantity of one of the following air tool
lubricants through the air inlet.
SHELL Naturelle HF
CASTROL Carelube HTG 22
Cleaning
At intervals of no more than 100 hours use, or
if operation becomes unproductive, or if any of
the pistons shows signs of sticking, dismantle
and clean with highly refined paraffin. Replace
any worn components as necessary.
Immediately after cleaning, thoroughly oil the
tool with one of the recommended lubricants.
Risk of Hand-arm
Vibration injury
These tools may cause Hand-arm Vibration
Syndrome injury if their use is not adequately
managed. We advise you to carry out a risk
assessment and to implement measures such
as; limiting exposure time [i.e. actual trigger
time, not total time at work], job rotation,
ensuring the tools are used correctly, ensuring
the tools are maintained according to our
recommendations, and ensuring that the
operators wear personal protective equipment
[PPE] particularly gloves and clothing to
keep them warm and dry.
Employers should consider setting up a
programme of health surveillance to establish
a benchmark for each operator and to detect
any early symptoms of vibration injury.
We are not aware of any PPE that provides
protection against vibration injury by
attenuating vibration emissions.
See „Specifications‟ section for vibration
emission data.
Further advice is available from our Technical
Department.
Pre-Start Check
The compressed air supply must be free from
water and dirt. The installation of a filter/
regulator/lubricator air preparation set (with
moisture trap) adjacent o the tool is strongly
recommended. Always clear the air hose
before connection to the tool. Ensure that no
moisture (condensation) is present in the air
hose. Ensure that a minimum 19mm (3/4”)
bore air hose is used and that all couplings
are secure; leak free and in good condition.
Limit the length of air hose to 15M (50ft).
Where extra length is necessary, for each
additional 15M (50ft) of air hose used, the
pressure drop is approximately 0.16bar
(3psi).
Correct operating pressure is 6.2bar (90
psi).
Do not let the operating pressure fall below
5.5bar (80p.s.i.) or rise above 6.9bar (100 psi)
absolute maximum.
Preferably, the compressor should be able to
supply a minimum of 33L/s (70cfm) free air. In
particularly cold weather it is recommended
that a proprietary anti-freeze lubricating oil be
used.
Starting Work
Prior to operating the tool check: -
That all fittings are secure, free from leaks
and air hoses are in good condition.
That all parts of the tool are fully screwed
together and secure, if in any doubt ask
your supervisor before using this
equipment.
That a liberal amount of lubricant has been
put into the air inlet of the tool. (See
recommended lubricants)
Safe use of this tool requires a solid stance
and secure foothold; the operator must adopt
a firm and stable position at all times. Depress
the foot mechanism (24) to release the
handle. Never run the tool with the handle
fastened to the main body. To operate the tool
turn the ball valve on the handle to the fully
opened position and immediately start to
move the tool back and forth, continue until
the desired finish is achieved. Never run the
tool continuously in the same place, as the
cutterheads will dig into the surface. If the tool
is new, optimum performance will be achieved
after 15mins “running in” of the brush seals
(48). To switch off, simply return the ball
valve lever to 90° to the handle whilst
continuing to move the tool back and forth,
return handle to the upright position, ensuring
foot release has engaged. Complete a small
area noting the performance; stop the
machine, inspect the finish produced. Handled
correctly the MHS11 Multi-headed Scabbler
will work quickly and efficiently.
Gloves and personal protective equipment
must be worn when using this tool. The tool
will ride irregularities of up to 13mm (1/2”).
Anything greater will risk cutterhead damage.
Care must be taken to avoid damaging or
tripping over the air hose.
Servicing
Only a competent person, in a suitably
equipped workshop, must carry out
maintenance.
Disconnect the tool from the air supply
before carrying out any of the following
operations.
Dismantling
After ensuring that the air supply is turned off,
remove the tool from the airline. Thoroughly
clean the outside of the tool prior to
dismantling.
Cutter Head Removal (Two Piece)
To change the replaceable cutter heads
without completely dismantling the tool.

SERVICING
nuts (59) and remove the u-bolts (57) and
mounting brackets (58).
Removal of Handle from Sub-Frame
Lay the tool on its front, with the handle
uppermost. Select two 24mm (15/16”A/F)
spanners and unscrew and remove nut (25)
and washer (27), and withdraw bolt (26) and
washer (27). Depress the foot handle release
lever and remove the handle from the
subframe.
ASSEMBLY
Assembly is generally the reverse of
dismantling. Before assembling, ensure all
parts are clean and all internal parts have a
film of air tool oil. Replace any parts that
show signs of wear. If the tool is being fully
serviced it is recommended to change anti-
vibration mountings (31) and (28), along with
the O‟Rings (44) and the brush seals (48). It is
good practice to replace the split pins (33) and
locknuts (29) and (25) during assembly.
Assembly of Pistons / Cylinder Head
Set the cylinder block in the upright position,
carefully placing supporting blocks
underneath to aid assembly, take care not to
block the exit holes for the pistons.
Cutter Head / Piston replacement (Two
Piece)
Fit the pistons (42) into the cylinders (43) and
insert all pairs into the cylinder block as per
service layout. Fit a new O‟Ring (44) into each
of the recesses on the outside of the cylinders
on top of the cylinder block. Lubricate each of
the pistons. Insert two bolts into the cylinder
head to act as a guide to align the head with
the bolt holes and carefully lower it into place
taking care not to disturb the O‟Rings or
trapping your fingers. Insert the 7 cap head
screws (41) and tighten initially by hand,
tighten to a torque of 55Nm (40lbs/ft).
Cutter Head / Piston replacement (One
piece)
Fit the pistons (52) into the cylinders (43) and
insert all pairs into the cylinder block as per
service layout. Fit a new O‟Ring (44) into each
of the recesses on the outside of the cylinders
on top of the cylinder block. Put a few drops of
recommended lubricating oil on top of each
piston. The cylinder head is very heavy,
carefully lower it into place taking care not to
disturb the O‟Rings or trapping your fingers.
Insert the 7 x cap head screws (41) and
tighten initially by hand, tighten to a torque of
55Nm (40lbs/ft).
Assembly of Exhaust Chamber / Cutter
Heads
Carefully turn the block assembly over on to
the cylinder head (39). Lower the exhaust
chamber (46) into position with the cavity
nearest the block (45), Fit new brush seals
(48) into the brush seal recesses and lower
the sealing plate (47) into position with the
brush seal recesses nearest the block. If a
brush seal is loose in the recess, pull the
brush seal apart slightly to make it a tighter fit.
Insert hexagon head bolts (49) through
sealing plate (47), exhaust chamber and into
cylinder block (45). Tighten initially by hand,
then torque the bolts down to 80 Nm (60lb.ft.).
If fitted, screw on the cutter heads (50) initially
by hand, select a 19mm A/F (3/4") spanner for
the flats of the piston (42) and a 27 mm
spanner for the flats of the cutter head (50),
ensuring that the new heads are tightened to
torque of 55Nm (40lbs/ft) and that both mating
faces are in contact with one another.
Sub-frame to Cylinder Block / Head
assembly
Align mounting holes on sub-frame with anti-
vibration pad (31) studs and fit as shown in
service layout. Fit washer (30) and locknut
(29) to both studs and fasten by hand. Screw
both nuts down to a torque of 40 lb/ft.
Wheel to Sub-Frame
Slide wheel (35) onto sub-frame axle, fit
washer (34) and insert a new split pin (33) into
the hole. Separate legs on split pin and bend
round with pliers. Repeat for the other wheel.
Handle to Sub-Frame
Fit new anti-vibration rubber mountings (28) to
the holes in either side of the handle (19) and
slide assembly into position between the axle
arms of the subframe (32), fit washer (27) to
bolt (26) and align all holes to allow the
insertion of the bolt as shown in the service
layout. Guide bolt through anti-vibration pads
(28) until it appears at the other end. Fit
washer (27) to threaded end of bolt and fit nut
(25). To ensure that the sub-frame does not
buckle through over tightening and that the
vibration rubbers are set correctly, tighten until
both washers are no longer free to rotate.
Ball Valve Mounting
The ball valve should be fitted so that the
valve is open when in line with the handle. Fit
one of the two u-bolts (57) around ball valve
(56) and through u-bolt clamping bracket (58).
Guide the u-bolts through the holes in the
mounting flange on the handle. Fit 2 x nuts
(59) finger tight to hold the unit in place.
Repeat with second u-bolt and bracket. Align
the ball valve lever with the main handle.
Select a 13mm A/F spanner and fasten evenly
four nuts (59) until valve is secure.
Vacuum Shroud
To fit the optional vacuum shroud assembly
(51) remove the eyebolt with a suitable bar,
then lay the tool on its front face, unlock the
handle and pull the cylinder block onto its top
face. Select a 19mm (3/4") A/F socket and
unscrew and remove the 5 x hexagon bolts
(49). Select an 8mm A/F (5/16”) spanner and
unscrew completely the front 3 x hexagon
head screws (53) and the associated front
clamp plate (52). Thread the tube of the
vacuum shroud assembly (51) through the
subframe (32). Align the holes and secure
using the 5 x 10mm cap head bolts supplied
with the vacuum shroud. Refit the clamp plate
(52) with the supplied screws (53) ensure that
the neoprene seal is square and securely
clamped. For dust free working it is
recommended that a Trelawny recommended
vacuum system be connected to the vacuum
shroud assembly.
Disposal
Dismantle into component form for disposal
according to material composition and
disposed of using waste recycling processes
specified by local regulations.
Note: Flammable material such as plastic,
rubber or composite materials must not be
incinerated but should be disposed of using
normal industrial waste disposal processes.
Remove the eyebolt (38) from the cylinder
head, then lay the tool on its front face, unlock
the handle and pull the cylinder block onto its
top face; select a 19mm A/F (3/4”) spanner for
the flats of the piston (42) and a 27 mm
spanner for the flats on the cutterhead (50).
Unscrew the cutterhead and remove from the
piston. It is also advisable at this point to
replace the brush seals, select a 19mm A/F
(3/4”) spanner and unscrew the 5 x hexagon
head bolts (49). Remove the bolts and sealing
plate (49/47). Remove the worn brush seals
(48), which may need prising out of their
recesses.
See: Assembly of Exhaust Chamber/Cutter
Heads.
Cutter Head / Piston removal (One Piece)
To replace the one-piece pistons (52), place
the cylinder block on wooden blocks so that
the cutterheads are clear of the floor. Unhook
the main handle from the chassis and lay the
handle on the floor. Using a 19mm (3/4")
spanner unscrew and remove the two-nyloc
nuts (29) from the upper vibration reducing
mountings. Using a 10mm Allen key, remove
the 7 x socket headed bolts (41) from the
cylinder head (39). Take care when removing
the cylinder head as it weighs 16.4kg
(36.0lbs), take extreme care against trapping
your fingers when lifting and placing the
cylinder head down, use a hoist or other
suitable lifting equipment whenever possible.
An eyebolt (38) is supplied fitted to the
cylinder head for this purpose. Remove the
O'Rings from the cylinders and remove the
piston and cylinder as an assembly. Inspect
the components for wear paying particular
attention to the small bore of the cylinder.
Exhaust Chamber removal
Remove replaceable cutterheads, if fitted (50),
sealing plate (47) and brush seals as in
“Cutterhead/Piston removal section".
Remove the exhaust chamber and clean out
any dust that may have accumulated inside
the chamber.
Removing Sub-Frame from Cylinder Block
Lay the tool on its front, with the handle
uppermost, select two 32mm (1 1/4”)
Spanners and unscrew the hose (60)
connector from the lower ball valve adapter
(55). Select a 19mm (3/4"A/F) spanner and
unscrew the 4 x locknuts (29) securing the
chassis to the vibration reducing mountings
(31) and remove all nuts and washers (29/30).
Cylinder Head removal
Repeat the above, place the cylinder block on
wooden blocks so that the cutterheads are
clear of the floor.
Select a 10mm A/F hexagon key and unscrew
the 7 x caphead screws (41). Withdraw the
screws and lift the head clear of the cylinder
block. Take care when removing the cylinder
head as it weighs 16.4kg (36.0lbs), take
extreme care against trapping your fingers
when lifting and placing the cylinder head
down, use a hoist or other suitable lifting
equipment whenever possible. An eyebolt
(38) is supplied fitted to the cylinder head for
this purpose.
Removing Ball Valve from its mounting
Select two 32mm (1 1/4”) Spanners and
unscrew the hose (60) connector from the
lower ball valve adapter (55). Unscrew hose
fittings from ball valve unscrew the 4-nyloc

SERVICING continued
Exploded View 1
Machine storage
Short period storage: up to 3months.
Clean the outside of the machine and inspect
the cutter heads for wear, replace any worn
parts as required.
Remove any build up of material from the
cutter head area.
Insert a liberal quantity of air tool oil through
the air inlet and run briefly to ensure that
internal components are coated with oil.
Cover the machine to protect it: Store the
machine in a dry place.
Long period storage: over 3months
Clean outside of machine, inspect the cutter
heads for wear; replace any worn parts as
required.
Remove any build up of material from the
cutter head area.
Insert a liberal quantity of air tool oil through
the air inlet and briefly run to ensure that
internal components are coated with oil.
Lubricate the exposed part of the piston and
cylinder. (See recommended lubricants)
Cover the machine to protect it: Store the
machine in a dry place.
After 6 months have elapsed, check the
condition of the hose then insert a liberal
quantity of air tool oil into the air inlet as
previously described and briefly run to ensure
that internal components are coated with oil.
Prior to using the machine again check the
condition of the hose and the vibration
mountings for signs of perishing etc, replace if
suspect, continue as per the “before use”
instructions.
When next used, continue as per “Pre-Start
Check” section.
Consumables
42 612.0125 Piston Bush (one piece) x 11
612.0120 Piston (Threaded) x 11
43 613.3001 Cylinder x 11
48 614.5302 Brush Seals x 11
50 426.5355 Bush Hammer Cutter Head x 11
426.5358 Cruciform Cutter Head x 11
SEE PAGE (5) FOR LIST OF ALL COMPONENTS

PART NUMBER LIST
Item No Part No Description Item No Part No Description
13 490.0200 Hand Grip (set of 2) 44 809.0500 Cylinder 'O'Ring - Prior Nov 2013 x 11
19 422.0120 Prior 2010 - Handle Assembly 809.0269 Cylinder 'O'Ring - After Nov 2013 x11
422.0125 2010 onwards - Handle Assembly 47 654.1120 Sealing Plate
22-24 491.4100 Prior 2010 - Foot Release set 48 614.5302 Brush Seals x11
491.4110 2010 onwards - Foot Release set 49 831.3120 Bolt M12 x 65 Hex Head x 5
23 714.0120 Prior 2010 - Spring *806.1265 Cap Head Screw M12 x 65 (For Vacuum Shroud) x5
713.0125 2010 onwards - Spring 50 426.5355 Bush Hammer Cutter Head (for 612.0120) x11
25-27 491.2000 Handle Pivot Bolt assembly 426.5358 Cruciform Cutter Head (for 612.0120) x 11
28 490.1000 Rubber Mountings (set of 2) 51 437.0120 Vacuum Shroud assembly (Inc 52,53,54 and *806.1265)
29-31 491.0200 Rubber Block mounting kit (set of 4) 52 492.0120 Clamp Plates (set of five)
32 440.0120 Subframe 53 490.3200 M5 Hexagon Head Screws (Set of 11)
33-35 491.1100 Wheel assembly (set of 2) 54 731.0120 Vacuum Shroud Seal
38 831.4120 Eye Bolt 55 826.5004 Adaptor 3/4 BSP x 3/4" BSPT
39/45/46 491.5000 Cylinder Block 56 828.1000 Ball Valve
41 806.1260 Caphead Screw (4 x required) 57-59 491.2100 'U' Bolt assembly (set of 2)
42 612.0125 Piston Bush (one piece) x 11 57 831.2000 „U‟ Bolt U' Bolt (2 x required)
612.0120 Piston (Threaded) x 11 60 719.0750 Armoured Hose inc fittings
43 613.3001 Cylinder x 11
SEE PAGE (4) FOR LIST OF CONSUMABLES
SERVICING continued
Exploded View 2

Trelawny SPT Ltd
Trelawny House, 13 Highdown Road, Sydenham Industrial Estate, Leamington Spa, Warwickshire,
CV31 1XT, United Kingdom
Telephone: [phone], Fax: [phone],
Email: [e-mail] Website: www.trelawnyspt.com
© TSPT UK 2009 Part No: 735.1120 issue 14.1.16
SURFACE PREPARATION TECHNOLOGY
Trouble Shooting
Technical Specifications
FAULT CAUSE ACTION
Machine bounces in use Air pressure to high. Ensure that the air pressure is set at 90psi. (6.2bar).
If the air pressure cannot be controlled, close the MHS11 on/off ball valve off
slightly until the machine runs smoothly.
Machine performance slow Worn Cutter Heads Replace Cutter Heads (Cutter Head life is approximately 100hrs use)
Machine drags on floor Insufficient air supply Ensure that the compressor can supply at least 70cfm (free air) at 90psi in order to
avoid air supply problems.
Hose bore too small Ensure that the hose bore is 3/4” (19mm).
Hose run too long Each 50 ft. (15 mtrs) of airline used, will drop the pressure by approximately 3 psi.
Worn Pistons and/or cylinders. Replace piston and cylinders
If problem has not been cured by any of the above actions, contact your local dealership or agent for assistance.
Blows per minute 2200 x 11
Air consumption 26.0 l/s (55.0 cfm)
Working height 1295mm (51.0”)
Packaged dimensions 305mm W x 356mm L x 813mm H
Weight 70kg (154 lbs)
Air hose bore - (Air Inlet Adaptor 3/4" BSP) 19mm (0.75”)
Removal rate * 28m 2/hr (300ft 2/hr)
Depth of cut (Average) * 3.0mm (.118”)
Cutting Width 250mm (9.84”)
Noise LPA SPL 97.4 dB (A)
LWA SWL 110.5dB (A)
Vibration (AEQ) 5.0m/s2(K= +40% -0%)
Trelawny SPT Ltd operates a policy of continuous product development and refinement and therefore reserves the right to change technical
specifications and product designs without giving prior notice.
*These values are guidelines only. Test concrete surface was one year old and the finish produced suitable for keying additional layers. The aggregate
was exposed but not severely damaged or disturbed.
Declared vibration emission values are in accordance with BS EN 12096: 1997
(K) Equals the factor of uncertainty, which allows for variations in measurement and production.
Vibration data figures are tri-axial, which gives total vibration emission.
Risk of Hand Arm Injury
Because of various factors, the range of vibration emission during intended use of this tool is expected to be between 5.0m/s2–7.0m/s2.
The vibration is dependent on the task, the operators grip, and feed force employed etc.
Noise level measured in accordance with EN ISO 15744: 2008
Vibration measured in accordance with EN ISO 28927:2012 and EN ISO 20643:2005
Noise and Vibration Declaration Statement
This tool has been designed and produced in accordance with the following directives:
2006/42/EC Machinery Directive
and applicable harmonised standard: EN ISO 1 1148-4:2012
If your company has any problem with our products or would like to discuss the possibility of an improvement being made to them, then please do not
hesitate to contact us. Your comments are both important and appreciated.
Machinery Directive Information
SERVICING continued