roundhouse Mildred User guide

Owners Handbook
For the Mildred Locomotive
Mildred

Operating Instructions
IMPORTANT: Read these instructions carefully before operating
the locomotive.
The following items are required for running this engine and are not
included with the model.
Fuel Butane gas. See 'Filling the gas tank'
Water See 'Filling the boiler'
Lubricating oilSee 'Lubrication'
SAFETY PRECAUTIONS
This is a working model locomotive using steam under pressure
and highly flammable fuel. Provided it is operated with reasonable
care and attention, no problems should arise.
It is intended for use out of doors and must only be operated in a
well-ventilated area.
Whilst the locomotive is in use, hot gasses are exhausted up the
chimney and excess steam frequently blows off through the safety
valve even when stationary, so operator and spectators should not
bend over the model.
As you will appreciate, this is not a toy and is therefore unsuitable
for young unsupervised children.
Follow manufacturer’s recommendations regarding the safe
storage of Butane gas canisters.
Some areas of the model will get quite hot whilst it is operating, so
a pair of gloves is provided in the tool kit for your protection.
Always have to hand either a fire extinguisher or wet cloth when
operating the model.
2

CONTENTS
Tool kit. Page 4
Running in. Page 4
Access to controls. Page 4
Identification of parts of the locomotive. Page 5
Preparations for operation.
1. Filling the Gas Tank. Page 6
2. Filling the Boiler. Page 7
3. Lubrication. Page 7
4. Lighting the Burner. Page 8
Running the locomotive. Page 9
Driving manually. Page 10
Driving by radio control. Page 11
Storage between operating sessions. Page12
Altering wheel gauge. Page13
Trouble shooting & maintenance.
Steam Leaks. Page 13
Regulator. Page 14
Radio Control. Page 15
Gas System. Page 15
Boiler and Gas Tank Certificate, Pages 17 & 18
(EC Declaration Of Conformity).
Service and Parts. Page 20
3
Mildred Instruction Booklet

TOOL KIT
The following items are included with your locomotive.
One 60ml bottle of special steam oil for use in the lubricator.
One 60ml syringe with plastic tube for filling the boiler with water.
One set of spare washers and ‘0’ rings.
One spare gas jet.
One Allen key for cylinder socket cap screws.
One wheel setting (back to back) gauge and key.
One pair of protective gloves.
One cleaning duster.
One wheel setting (back to back) gauge and key.
RUNNING IN
All locomotives are extensively test run before leaving the factory,
but they will still require a certain amount of running in when new,
to overcome initial tightness and allow valves etc. to ‘bed in’.
ACCESS TO THE CONTROLS
For normal operation, all controls are accessible without the need
to remove any part of the locomotive, however, to give access to
the gas tank when filling, the cab roof hinges up from the side.
Care should be taken when opening the cab roof. Gently grasp
either side of the roof hinge and firstly lift the hinge vertically
upwards. This will lift the hinge clear of the cab, and allow the roof
to then tilt to the side. The gas regulator is accessible through the
rear of the cab, and on manual control engines, the steam regulator
is accessible through the right hand cab doorway and reversing
lever through the left hand cab doorway.
The radio control receiver and switch are housed on the right hand
side of the chassis, just below the cab floor.
The batteries for the radio control system are housed in a holder
beneath the cab roof. Refer to the manufacturers instructions
supplied with the radio control,
4

IDENTIFICATION OF PARTS OF THE LOCOMOTIVE
Radio controlled version illustrated
1 ) Lubricator drain screw. 2 ) Lubricator filler cap.
3 ) Reversing servo (this is replaced by a
reversing lever on manual models).
4 ) Pressure gauge. 5 ) Safety valve. 6 ) Gas regulator.
7 ) Gas filler valve. 8 ) Steam regulator.
9 ) Steam regulator servo and linkage (not fitted
on manual control engines). 10 ) Gas burner.
5

PREPARING FOR OPERATION
The locomotive must be serviced before being operated. It is
important to perform all the following operations.
1) FILLING THE GAS TANK
The filling of the gas tank should only be carried out in a well-
ventilated area, where there are no naked lights or other lighted
locomotives close by. Ordinary Butane or Iso-butane gas (as used
in gas cigarette lighters) is the preferred fuel, though for economy,
the larger canisters as used for blowlamps or camping stoves etc.
are better.
The larger canisters have an EN417 threaded self sealing valve on
top and require a special adapter to couple up to the filler valve on
the locomotive. A special brass gas filler adapter is obtainable from
your local garden railway supplier or direct from ROUNDHOUSE.
Mixed gasses are also available and may be used if ordinary
butane or iso-butane are not available, but see ‘Gas System’
section for more information on this subject.
Before attempting to fill the gas tank, make sure that the gas
control valve is closed by turning it clockwise.
The filler valve for the gas tank is on top of the tank under the cab
roof. Invert the gas canister and place its nozzle over the gas filler
valve. Support the tank from underneath and press the canister
down.
The gas will be heard hissing as it enters the tank and a small
amount will escape around the valve. This is quite normal and is
the tank venting as the liquid enters.
After about 20 to 30 seconds, liquid gas will emerge from the valve
showing that the tank is full. Remove the canister immediately.
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2) FILLING THE BOILER
A syringe and plastic pipe are supplied for filling of the boiler.
The boiler is filled with water through the safety valve bush, housed
inside the brass dome on top of the boiler. The brass dome is a
substantial and heavy item, being turned from solid brass. Care is
needed when removing the dome, especially when the engine is
hot, as the dome itself will be hot. Take care not to drop the dome
onto the locomotive, as the weight of it may damage the model. Lift
off the brass dome then remove the safety valve by unscrewing the
large knurled plug into which it is fitted.
Using the 60ml syringe and plastic tube supplied, fill the boiler fully
to the top with clean water. Distilled water is recommended if
available. As an alternative in soft water areas, clean tap water can
be used. Also, rain water or water from a dehumidifier may be used
provided that it is adequately filtered. Many people use rain water
passed through a wine or coffee filter to remove any particles or
debris.
Do not use deionised water as this type of water in the long term,
may cause damage to the boiler and fittings.
There has to be a space above the water to allow steam to be
raised so, insert the end of the plastic pipe into the boiler and
withdraw 30ml of water with the syringe. Replace the safety valve
finger tight.
3) LUBRICATION
Regular lubrication of all working parts is important and should be
carried out before each operating session. There are two types of
lubrication required: The external moving linkages and bearings are
lubricated with a medium oil such as motor engine oil, and the
internal steam mechanisms such as cylinders, pistons and valves
are lubricated with a special steam oil that is mixed with the steam.
Infrequent external lubrication will allow parts to run dry, and over
oiling can form pools around operating parts that attract dirt and
grit. If too thin an oil is used it will evaporate very quickly as the
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8
loco gets hot –leading to dry running. We recommend the use of a
20-50 motor oil for external lubrication.
Internal lubrication is achieved by steam oil that is mixed with the
steam in the displacement lubricator, housed in the left-hand side
of the cab. Remove the knurled cap from the top and slacken the
drain screw two or three turns at the bottom but do not remove it.
Any water in the lubricator will run out through the drain screw.
Tighten the drain screw and refill with the steam oil supplied, then
replace the cap.
Take time filling the lubricator, especially when cold, as the oil
takes time to run down and may trap an air bubble. Both cap and
drain screw are fitted with ‘0’ rings and need only be closed finger
tight.
NOTE: Only special steam oil as supplied should be used in the
lubricator and under no circumstances should ordinary oil be
substituted, or damage may result. The gas and steam regulators
will require periodic lubrication –see the troubleshooting section for
details.
4) LIGHTING THE BURNER
WARNING: Before lighting read the ‘Gas System’ section further
on ion this booklet, and be aware of potential problems. If the gas
system is not operating correctly, shut it off immediately or
damage may result.Move the locomotive to another location before
lighting. Butane is heavier than air and small pockets of gas can
collect around the locomotive during filling.
To light the burner, hold a lighted match or cigarette lighter over the
top of the chimney and slowly open the gas regulator by turning it
anti-clockwise. The gas should ignite almost immediately with a
pop as the flame travels down the chimney and into the boiler tube.
The burner should be audible but not too loud.
NOTE as stated above, the gas regulator should be opened slowly
until the burner ignites. If opened too quickly, particularly when the
engine is cold or if the gas tank has just been filled, it is possible

that the flame may not travel back into the boiler flue but stay in the
smokebox. If this should happen, the burner will sound quite
different to normal and the blue flame will be visible in the
smokebox if viewed down the chimney from a safe height. Should
this happen, turn off the gas immediately or damage may result
and then re-light it.
If the problem persists and it is not possible to ignite the burner
correctly, then a dirty jet should be suspected and cleaned as in the
Gas System Troubleshooting Section.
For the first couple of minutes keep the burner on low. This is
important, as until it warms up, the flame will be a little unstable
and turning it up too much could cause it to go out. Also, with a
completely full tank, liquid gas could be drawn off instead of
vaporized gas, which can also extinguish the flame.
After a couple of minutes, the gas control valve can be opened
more to speed up steam raising. Open the gas regulator slowly to
about one full turn.
The full range of adjustment (closed to fully open) is achieved
within the first full rotation of the gas regulator knob any more is
unnecessary.
RUNNING THE LOCOMOTIVE
When full working pressure has been reached (about 40psi), the
safety valve will start to blow off steam. Steam generation can be
controlled by the gas valve in the cab. If the safety valve blows off
frequently during running, then too much steam is being produced,
which wastes water and gas. Turning down the burner will
decrease the amount of steam created. Conversely, if steam
pressure is not maintained during a run, then the burner should be
turned up.
After a few minutes of running it may be noticed that the gas
pressure through the burner has increased. This is due to the gas
tank becoming warmer and so increasing the gas pressure. Simply
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turn the gas down –this may need to be performed several times
during a run. The art of balancing steam generation to the
operational requirement by the adjustment of the gas control valve
will quickly be learned.
The gas tank has a duration of about 25 minutes, though this will
vary a little depending on gas valve setting. The boiler should not
be allowed to run dry, and the gas tank capacity is such that the
gas should run out before the water. When the gas is fully used up,
the steam pressure in the boiler will be seen to gradually drop until
the loco comes to a halt. Should the water expire before the gas is
fully used, the pressure will drop rapidly and the loco will stop.
Check the pressure gauge –if this is zero turn off the gas. No
damage will result if the gas is turned off immediately.
DRIVING THE LOCOMOTIVE MANUALLY
On manually controlled locomotives, there are three main controls,
all of which are housed in the cab.
1) The gas regulator, which should be used to control steam
generation as described earlier.
2) The reversing lever. This is in the left-hand side of the cab and is
moved fully forward for running in a forward direction and full back
to run in the reverse direction. It should be parked in the centre
(mid gear) when the locomotive is stationary for any length of time.
When in mid gear position, the valve gear is effectively in neutral
and the engine will not move under steam power.
3) The regulator. This is the main steam control valve and
regulates the speed of the locomotive. The regulator handle is
situated in the right hand cab doorway and is moved anti-clockwise
to open and clockwise to close.
Using the reversing lever, select the desired direction of travel and
open the regulator a little. Initially, there will be a certain amount of
water in the pipes and cylinders, which will exhaust through the
chimney and, after a few moments, the engine will move jerkily,
10

until this clears. Once the parts have warmed up, the engine will
move off steadily and its speed can be controlled with the regulator.
Subsequent starts will be quite smooth once the cylinders etc. have
reached their normal operating temperature.
To reverse the locomotive, close the regulator to bring it to a halt,
move the reversing lever over and open the regulator again.
The art of fine control will soon be learnt with a little practice.
DRIVING BY RADIO CONTROL
This model is fitted with 2.4 GHz R/C equipment. On a Radio
Controlled model, speed and direction are controlled by the
transmitter. First, turn on the transmitter and then switch on the
receiver on the locomotive with the switch on the right hand side of
the chassis, just below the cab footplate. The left hand stick on the
transmitter controls the steam regulator, down for stop up for go.
Moving to the left or right has no function.
The right hand stick operates the reverser, left for forward and right
for reverse. This stick is sprung loaded to return to its central
position. Moving up or down has no function
Using the transmitter, select the desired direction of travel and then
slowly open the regulator. The locomotive will now move off as
described in the manual control section.
For more information on using the radio control equipment, see the
manufacturer’s instruction booklet supplied with the Radio Control
Set.
The art of fine control will soon be learnt with a little practice
NOTE: Ensure that the valve gear is fully in gear for the required
direction when the engine is moving. The model is fitted with a
simplified Walschaerts type valve gear which is not suitable for
'notching up' (altering the cut off). Always bring the locomotive to a
halt by closing the regulator before changing direction. If an
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12
emergency stop is required, simply release the reversing lever,
which will spring back into mid gear and halt the train. Then close
the regulator. Always ensure that the regulator is closed before
switching off the transmitter.
Always switch off the receiver and transmitter when not in use to
preserve battery life. It is good practice to switch on the transmitter
before the receiver and switch off the receiver before the
transmitter. In this way, the radio receiver is never on when the
transmitter is switched off and so will always be under your control.
When the batteries are getting low, a poor signal between
transmitter and receiver will result and control of the engine will
become erratic. Refer to the instructions supplied with the radio
control equipment. The receiver batteries are housed in a holder
beneath the cab roof.
STORAGE BETWEEN OPERATING SESSIONS
At the end of an operating session, it is good practice to clean the
locomotive carefully with a clean soft cloth, and to oil all bright
metal parts.
Do not leave fuel or water in the tank or boiler for long periods.
Do not store in places where the temperature may drop below
freezing as water may still be present in the pipework.
Ensure all controls are closed and the valve gear in mid gear.
Ensure that radio control equipment is switched off and, if the
engine is not to be used for some time, remove all batteries.
Periodically it may be necessary to wash off all traces of dirt and
old oil from the moving parts with paraffin (not thinners). This will
remove any accumulations of dirt or grit. After washing with
paraffin, leave to dry thoroughly overnight before re-oiling. It is
most important that clean oil is applied and allowed to penetrate
fully into all moving parts before the locomotive is run again.
Manually moving the locomotive back and forth will assist in
distributing the oil fully. Under normal operating conditions this
procedure should not be required more than once or twice per

year.
ALTERING WHEEL GAUGE
The wheels are set at the factory for the specified gauge however,
for those who wish to alter this to run on other people’s railways or
if you change the gauge of your track, they are easily reset with the
aid of the back to back gauge supplied in the toolkit.
The driving wheels are moveable on their axles and are locked in
place by a small grub screw. They should be adjusted so that the
"back to back" gauge supplied in the kit will just slip between their
inner faces.
Ensure that the wheels are evenly spaced relative to each side
frame.
Do not over tighten the grub screws particularly on insulated
wheels.
TROUBLE SHOOTING & MAINTENANCE
On a working model of this nature, it is important to keep all
working parts well lubricated.
With constant heating up, cooling down and the stresses of hard
work, screws etc. can work loose so, it is good practice to check all
fixings and cylinder screws regularly but remember, never over
tighten.
STEAM LEAKS
With constant heating up, cooling down and the stresses of hard
work, screws etc. can work loose so, it is good practice to check all
fixings and cylinder screws regularly but remember, never over
tighten.
The cylinders are fitted with '0' rings in the glands sealing both
piston and valve rods. These can be adjusted with a spanner if
steam leaks develop. They should only be tightened just enough to
stop the leak, as over tightening will affect the running of the model.
13

REGULATOR NOT SHUTTING (R/C models)
The steam regulator seating and seal can, after a period of time
become worn or compressed so that when the lever on the radio
control is fully closed, the locomotive still moves. To overcome this,
a trimmer is fitted to the transmitter. This is the small lever at the
side of the main control lever and is set at the factory to the top of
its slot. As wear takes place in the regulator, it can slowly be
moved down the slot to compensate. When it reaches the bottom, it
is time to reset it to the top and adjust the linkage between the
servo and the regulator in the cab. If adjustment does not cure this
problem, the internal '0' ring is probably damaged and requires
replacement. Contact the factory for further advice.
Periodic oiling of the gland will help keep the regulator working
freely. Place a spot of motor oil between the gland nut and the
regulator arm and work the regulator a few times.
RADIO CONTROL
If the radio control gives problems, always check the batteries first
and replace if in doubt. For further details of the Radio Control
equipment, refer to the manufacturers literature supplied.
GAS SYSTEM
Internally fired locomotives are fitted with our 'FG' type gas burner,
which is set up and fully tested at the factory.
This system is designed for use with Butane or Iso-Butane gas.
Mixed gasses, i.e. Butane with a proportion of Propane mixed in,
are available, and may be used if straight Butane is unavailable.
These come in a variety of mixes ranging from 90/10 to 60/40 with
one of the most common being 70/30. The figures refer to the
proportions of the mix i.e. 70/30 contains 70% butane and 30%
propane. If using mixed gasses, always choose the one with the
largest proportion of butane. The addition of propane slightly alters
the gasses properties. This can make the burner a little more
difficult to light when cold or after filling the gas tank.
Always open the regulator very slowly when lighting, and only just
sufficient for ignition to take place. Opening too much too soon may
14

extinguish the flame until the burner reaches normal operating
temperature.
The tiny jet in these units can become blocked by small particles of
dirt making the burner difficult to light, burn weakly at normal
operating temperatures*, burn in the smokebox or fail completely. If
any of these should happen, clean out the jet as follows. (* On very
cold days, a burner may start off burning weakly due to the
temperature of the gas but should increase to its normal level as
the engine warms up. This is quite normal) .Carefully, disconnect
the gas pipe from the gas jet holder using a 2BA spanner.
Note when connecting or disconnecting the gas pipe and jet block,
do not use excessive force. Always hold the end of the gas burner
near the air holes to support it otherwise it is possible to cause
damage by bending the body.
Slacken the screw retaining the gas jet holder and slide it out to the
rear. Remove the jet from the gas jet holder using a 4BA spanner.
Wash out the jet in fast evaporating thinner (Cellulose or similar).
Blow through the jet from the front, which should clear most
blockages. Although the hole through the jet is tiny, if you hold it up
to the light you should be able to see quite clearly if it is blocked or
not. If in doubt, fit a new jet. A spare gas jet is included with the
toolkit. Do not use wire to clean the jet as this can damage the
precision hole and may upset the delicate balance of the gas
system.
Reassemble in the reverse order, putting a small amount of PTFE
tape round the thread of the jet. Ensure all connections are tight.
When re-positioning the gas jet holder in the burner, ensure that it
is pushed in as far as it will go. The gas regulator has a spindle ‘O’
ring housed inside the body which may need lubrication from time
to time if the control becomes ‘spongy’ in operation, making precise
gas control difficult. As stated in the lighting instructions the full
range of adjustment for normal burner operation is achieved within
the first full rotation of the regulator knob, and it should only be
unscrewed more than this for maintenance purposes and when the
15

tank is empty, and there are no naked lights nearby.
To lubricate it, remove the knurled knob which is retained by a M3
socket grub screw (M 1.5 AF Allen key required) in the side. This
grub screw is accessed by first removing the brass lever which is
screwed into the same hole.
Beneath the knob is a back-lash spring which will slide off the
spindle.
Unscrew the hexagon retaining nut then screw the spindle out of
the body.
The ‘O’ ring can now be lubricated.
Replace the spindle followed by the retaining nut. Slide the
backlash spring over the spindle and replace the knob. Note that
the grub screw that holds the knob in place tightens into a groove
near the end of the spindle.
16
Gas Regulator (Internal Parts)
Regulator
Body
Back-Lash
Spring
Regulator
Spindle
White PTFE
Washer
Knurled
Knob
‘O’ ring to be
lubricated
Hexagon
Retaining
Nut

EC
ROUNDHOU
SE
ENGINEER
ING CO.
LTD.
Units 6-9
Seri
Dated ………………..........
Model: MILDRED
Signed
R. Loxley (director)
Ves-
sel for
Group
1 gas-
ses and
associ-
ated pipe
Model: Type ‘A’ gas tank Serial No.:
Test date:
Ste
am
Ge
Model: Type 1 boiler Serial No.:
Test date:
17
De

Please refer to the ‘owner’s handbook’ for your particular model of
locomotive, for details on correct use of these pressure vessels.
Pressure vessel care and maintenance
Gas tank
The gas tank is used for the storage of LPG (liquefied petroleum
gas) in the form of butane, iso-butane or as set out in the ‘owners
handbook’.
The tank is fitted with a self-venting filler valve which contains no
serviceable parts. Should the filler valve become defective in any
way, it must be replaced with a new item.
It is recommended that the gas tank should undergo the following
checks, carried out by a ‘competent person’, club, society or
pressure vessel manufacturer, every year:-
1) thorough visual inspection.
And every five to ten years:-
1) hydrostatic pressure test to not less than 1.5 and not more
than 2 times the maximum working pressure.
Boiler
The boiler is fitted with a safety valve to prevent the steam
pressure rising above the maximum allowable working pressure.
This is pre-set to open at between 2.38 bar (35 psi) and 2.72 bar
(40 psi) and must not be adjusted to increase this value.
If the safety valve becomes defective in any way, it should be
replaced or returned to the factory for service and calibration.
It is recommended that the boiler should undergo the following
checks, carried out by a ‘competent person’, club, society, or
pressure vessel manufacturer, every one to two years:-
1) thorough visual inspection.
2) hydrostatic pressure test to not less than 1.5 and not more
than 2 times the maximum working pressure.
3) steam test to check the correct functioning of all steam
controls, gauge and safety valve.
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Gas Burner
1). Superheater Pipe. 2). Lubricator Pipe.
3). Gas Jet Holder retaining screw. 4). Gas Jet.
5). Gas Jet Holder. 6). Gas Pipe.
7). Gas Burner fixing screw. 8). Air Inlet Holes.
19

If your dealer is unable to help, you may contact the Factory directly:
ROUNDHOUSE ENGINEERING CO. LTD.
Units 6-10 Churchill Business Park. Churchill Road.
Wheatley. Doncaster. DN1 2TF. England
Telephone [phone] Fax [phone]
e-email [e-mail]
SERVICE AND PARTS
If' any problems arise with this model which are not covered in
these operating instructions or, spare parts are required, owners
should first contact their local dealer. Your ROUNDHOUSE dealer is;
20
www.roundhouse-eng.com
ONLINE