mamod safety valve free sample

I was given A Mamod TE1A Traction engine for my Birthday when I was fourteen and forty two years later I want to refurbish it, I would like to make a new safety valve, I am aware I could buy a new one but I have the means and ability to make and test one, the operating pressure is 10 - 12 psi, my only problem is how do I calculate the spring required and again I could measure my old one but then I learn nothing.

I had one of their stationary engines bought at a jumble sale back in the sixties. The screw in safety valve/ water filling plug had a very poor seal. I cut a short section out of a bike pump connector to replace it. I guessed the length, not having any means to test it and was lucky not to have blown myself up.

As Martin says but remember a safety valve has hysteresis. The force on the spring to get it to open initially is as stated but as it opens the spring compresses (closing force increases) and the area exposed to pressure increases (so opening force increases) so unless you choose a spring with the correct "rate" the boiler pressure drops below the lifting pressure before the valve closes - wastes precious steam. To determine the rate you also need to estimate the lift and calculate the force from the steam pressure on the increased area - this isn"t so easy as the steam is expanding at this point too where it is throttled by the valve so its a dynamic state rather than a steady state. Not so easy to calculate and the reason why on many miniatures the valve lifts at say 100psi but does not reseat itself until the pressure has dropped to say 80psi or less. One reason why you see people clouting model valves with shovels lol. 5 psi hystereresis is probably pretty good for model valves in general use although pop type valves can be tuned better.

Mamod safety valve is quite weak so fit a soft spring and try it if it to high when you trial it it"s no big deal the pressure if to high will push the piston off it"s seat

Hi Martin, what thread sizes did Mamod use for the boiler fittings? (Whistle, valve, drain). Dad has a couple or three engines with the various bits missing.

Hi Martin, what thread sizes did Mamod use for the boiler fittings? (Whistle, valve, drain). Dad has a couple or three engines with the various bits missing.

This talk of safety valves brings to mind a friend who used to work in Stuart Turner Models when they were still in Henley. One day a school teacher came in with one of Stuarts oscillating engines with a boiler. He had some issue with the engine, but the chap in Stuarts was horrified to see that the teacher had removed the spring and ball from the safety valve "because it kept sizzling" and replaced it with a screw and nut. The teacher(?) got a good telling off before he left. I hope he learned something!

There was a series in EIM about safety valves and springs, and many years ago one by Bill Hall in ME. Basically you have to ensure that not only will the spring keep the valve shut until it reaches operating pressure, but it will then open wide enough to release all the steam the boiler can make without allowing the pressure to rise too much. Probably not a big problem with a Mamod boiler.

Its not about how much my time is worth its the fact that I"m capable of making one, I dont make engineering models I make parts whilst restoring old stationary engines to get them running again and making the safety valve is easy enough but I have to get the spring correct otherwise it will leak or damage the boiler hence my question.

I was given A Mamod TE1A Traction engine for my Birthday when I was fourteen and forty two years later I want to refurbish it, I would like to make a new safety valve, I am aware I could buy a new one but I have the means and ability to make and test one, the operating pressure is 10 - 12 psi, my only problem is how do I calculate the spring required and again I could measure my old one but then I learn nothing.

Instead make the valve adjustable my having a threaded stem (towards the end) with two nuts. This is how some other manufacturers made theirs, Fleischmann comes to mind I think.

Mamod is a British toy manufacturer that specializes in manufacturing live steam models. The company was founded in Birmingham by Geoffrey Malins in 1937. The name is a portmanteau of Malins Models. The first models produced were of stationary steam engines, originally sold under the "Hobbies" brand name. Malins soon switched to selling them under the name "Mamod." The company later began creating models of road rollers, traction engines, steam wagons, and other steam road vehicles. These models were aimed at the toy market, so they were simple to operate and ran at low boiler pressures for safety but were not accurate scale models.

Most Mamod models use oscillating cylinders, usually single-acting. Some of these engines have regulators in either the steam feed or exhaust, but many others run unregulated (in the simpler models) or have a simple reversing mechanism to alter the cutoff, thus controlling the power/speed and direction of the engine. Early models had single or multi-wick lamps or vaporizing spirit burners, but in the mid-1970s the company changed to hexamine solid fuel which came in tablet form and provided low heat in a relatively safe form.

Two Mamod SE3 twin-cylinder steam engines from 1969. The engine on the left is the Griffin & George version, the version on the right displays push button whistle and screw-on crank webs.

Mamod Minor engines from 1949 and 1954. The red disc-crank version is the earlier engine, whilst the 54 version clearly shows the red "unclipped" mazak flywheel.

By 1948 the SE range had received its first real update. Mamod branded brass engine frames and hot-stamped brass flywheels were introduced and the SE1 and SE2 each received a regulator as well.

At the start of 1954 the SE range all received raised bases as well as cosmetic updates and changes. By 1958 all but the MM1 had received the new vaporising spirit burners, which had first appeared in 1957 with the introduction of the all new twin cylinder SE3. Again there was another round of cosmetic changes with updated boiler bands and fireboxes. Combinations of these old and new parts can be found in the "transitional" engines of the late 1950s period (e.g. the SE1, 2 and MM2). By the mid-1960s the engines were using pop rivets for the engine frame securing method (along with the entire Mamod range) as well more cosmetic changes. In 1967, the SE range received its next major update with the introduction of the SE1a and SE2a replacing the SE1 and 2. The superheating was gone and the simplified pipe work was all new. The SE2a also got a reversing lever like the "MEC1" Meccano engine of 1965. Other details such as paint colour, boiler end cap and whistle design as well as decal layout were gradually changed.

One point worth mentioning is the fact that from 1967 until about 1972, the Se1, 2 and 3 could be found with a different green paint on their engine frames. This paint was similar to a hammered effect type finish, and was most likely purchased as a job lot by the Managing Director at the time, Eric Malins. Steve Malins has confirmed that this was the case and his father would try anything new or changes which made production cheaper. The Minor range never received this paint finish. The SE3 was unchanged bar the introduction of the Griffin and George (educational suppliers) version in 1969. This engine was the only real variation to Mamod"s biggest post-war stationary engine. It featured the very first silver soldered boiler (at the insistence of G&G) and also had a steam pipe union nut at the boiler instead of the usual stop cock. It carried an extra foil G&G lozenge logo by the engine as well. About 2,000 were made until about mid-1970s. It was sold only to schools and came complete with a comprehensive manual for using the engine in laboratory experiments. Later examples of this engine were standard SE3s but carrying a revised G&G logo of a different design. This Griffin badge could sometimes be found placed alongside the warning labels applied to all stationary engines in 1976 explaining the use of inappropriate fuel containers and refuelling techniques.

In general, the SP models are modernised versions of the earlier SE models, the changes being for safety as well as cosmetic reasons. There is no strict correspondence between models in the SE and SP ranges. A rough comparison between the ranges can be seen in the following table:

After the Meccano branded version was discontinued, the same engine, with minor modifications, was later sold under the Mamod brand as the SP3. The original Meccano branded version never had an official name or model number but it is now commonly called the MEC1.

The SP1 was based on the Mamod Minor 1 which it replaced and which had been in production since 1939. It had the same boiler, similar engine unit and flywheel to the non-crankdisc types. The main differences were that it had a new black die-cast chimney and a narrow solid fuel burner design to take one tablet broken in half. This was also the only SP engine to feature a water plug as the boiler was too small to fit the standard Mamod water sight glass. The firebox remained the same as the older Minor 1. Some were built with the old Mamod Minor 1 boiler. The exhaust was a simple open port as on the Minor 2 and MEC1 engines. These engines with limited power and torque could drive at least 1 or 2 miniature tools.

The SP2 was an all-new design introduced in 1979. It replaced the Mamod Minor 2 and was similar to it in a few ways. It had the same type of boiler as the Minor 2 as well as the engine unit and frame. The exhaust was a simple open port like the Minor 2. The SP2D is a version of the SP2 with an integral dynamo. The SP2D has a larger-diameter flywheel which drives the dynamo – mounted inside the base of the chimney – by a belt. A small LED bulb is fitted to the top of the chimney. These were powerful engines for their size and could drive a full workshop of four tools quite easily.

The SP3 was based on the MEC1 Meccano engine, which had first appeared in 1965. It was basically the same except for a solid fuel burner, sight glass, a whistle instead of the steam dome and plastic gears, instead of metal ones, on the crank shaft for driving Meccano models. The exhaust was a simple open port in the engine frame as per the MEC1 and the engine carried two makers" marks — a Mamod and a Meccano type scalloped edge decal. The baseplate was silver painted and the boiler was a standard Mamod drawn type tube as used on the SP2, SP4 and SR1a. The SP3 could drive the whole series of workshop tools.

The SP4 was the mid-range engine in the SP series. It featured the standard Mamod drawn boiler and die cast chimney. The engine frame for this model was mounted on a silver plinth, and the unit had a reverser which allowed the engine to run in either a reverse or forward direction. It could drive a good selection of tools simultaneously, using a lineshaft, and it also featured "exhaust to chimney". The boiler was heated using the two-tablet burner tray as on the SP2 and 3, and a whistle was also included on it. The SP4D variant had a uni-directional engine unit and carried a larger pulley to drive a dynamo connected to a small 3v lamp.

The SP5 was the top-of-the-range engine when it was introduced. It had a longer boiler – 6 in × 2 in (152 mm × 51 mm) – and a twin-cylinder engine unit with a reverse control. The engines could easily drive several workshops due to their bigger boiler and twin cylinders. The engine, like the SP4, had the exhaust to chimney with condensate collector at the base of the chimney. The engine unit, like the SP4 was mounted on a plinth, a possible throw back to the SE4 prototype of 1946. The crank webs had the word Mamod stamped into them like the old SE3 it replaced. The boiler was heated using a 3-tablet burner pan, a whistle was also included in the specification.

The single-cylinder SP6 1338 is one of the most powerful engines Mamod have produced, and is fitted with a piston valve and fixed cylinder rather than an oscillating cylinder. It uses the same boiler/burner unit as the SP5 Mk2 1335 (optionally fitted with a pressure gauge). The same engine block has been used on the larger mobile models. Originally introduced in 2006, production of this model is still ongoing.

The twin-cylinder SP7 is the most powerful engine Mamod have produced, and is like the SP6 in the range, but is fitted with twin cylinders. It uses the same boiler/burner unit as the SP6 (fitted with a pressure gauge). The SP7 was introduced in 2009, and was available by special order only, but they stopped making them in 2018.

The SP8 is Mamod"s first beam engine. Introduced in 2013, it uses the same double-acting piston valve cylinder (as used in other recent models) which is mounted vertically under one end of the beam connected to it, using a simulated Watts linkage. The crankshaft and flywheel are mounted under the other end; the valve gear is controlled via a second smaller beam. The SP8 is offered with optional gas or solid fuel burner. Now discontinued.

The tools have featured in the Mamod range of steam toys since the company"s inception in 1937. Very early tools featured simple flat bases with Meccano-spaced holes. These early tools also had Meccano-like pulleys, fitted with crudely-made sand cast iron bodies. They continued after the war in the pre-war form until 1948 when, along with the SE1, SE2 and MM2 engines the hammer and Power Punch (later "Power Press") they were fitted with the new hot stamped brass flywheels. At the same time Malins Engineers moved to Camden Street, Birmingham. With this move the company acquired some power presses, and the new brass-wheeled tools (and polisher/grinder) began to get raised bases.

The line shaft is the accessory that enables a steam engine to drive more than one tool. The line shaft first appeared back in 1936 when Geoffrey Malins took on the task of making a set of engines for Hobbies of Dereham, after Geoffrey Bowman-Jenkins left Bowman models. The early line shafts all featured flatbases and, before the war, came in two models: the C1 and the C2; the former having 4 pulleys and the latter having 7. Both types of line shaft carried the Meccano-type red pulleys as well as turned brass types. The pedestal supports, like those of the early tools, were made from cast iron and the baseplates were drilled to fit Meccano. Production of the line shaft and the tools continued right up to the beginning of Second World War (and possibly into 1940), the line shaft by then being incorporated into the SC2, 3 and 4 engines. After the war (c1948) the line shaft gained brass pulleys as well as the hammer and punch. The flat base plate was retained but the C1 line shaft was dropped. By the mid-1980s the Mamod company was in trouble; the SP1, 3 and 5 were discontinued, along with the separate tools and line shaft, but all five components continued to be made as part of the WS workshop.

Mamod produces a wide range of models capable of moving under their own power. They are mainly generic representations of various vehicles that were often steam powered in the past.

The SR1 steam roller was Mamod"s first mobile steam toy. It was introduced in January 1961, designed by Eric Malins. The first rollers were unidirectional and only travelled in a "forward" direction (at an un-steam roller like speed). The engines featured a modified MM2 steam unit complete with characteristic rolls made of aluminium alloy. Like the early TE1s of 1963 and the stationary range, the early SR1 rollers were of screwed-together construction and also featured a brass vaporising lamp rivetted to the scuttle. They had no towing hook. From 1963, a revised burner was used (as was introduced with the TE1 steam tractor), the handle of which formed a towing hook; although it would be 1969 before there was anything for it to tow, with the introduction of the OW1 Open Wagon and LB1 Lumber Wagon. From 1965 the roller was put together using pop rivets (like all the Mamod range of steam toys) – as a result it is easy to distinguish early 1960s rollers from later ones. In 1967 the SR1 became the SR1a, with the introduction of a simple reversing mechanism on the engine unit. The mechanism was similar to the 1965 MEC1 Meccano engine. In the same way, the TE1 became a TE1a. In 1968 the aluminium rollers and wheels were replaced by Mazak items; the same material is used to this day. The roller has remained in the Mamod range for over 60 years now but has undergone small incremental changes over this time, with modifications to the burner (moving to solid fuel circa 1976) and sight glass boilers replacing the over flow plug type (circa 1978). The only other changes have been largely cosmetic: paint, whistles, smoke box detailing. Early boxed SR1 engines now command strong prices and are sometimes referred to as "nut and bolt" SRs by collectors. Lately, other variations of roller have included limited editions in different colours as well as longer boiler versions and also a kit version. The 60th anniversary of the introduction of the SR1 was celebrated in 2021 with a limited production run of 60.

This is the "classic" Mamod model and has been in production with minor updates and modifications for over 50 years. It is a model of a typical traction engine with a full-length canopy. The engine itself is an oscillating-cylinder unit, the same as the SR1/a which is based on the old MM2 unit. The boiler is longer than that on the SR1 although it is the same volume internally. The front part is an empty void into which, in the earlier versions, the exhaust steam was fed through the choke (it controlled the exiting steam not the inlet steam). The TE1a differs from the TE1 in having a reversing lever to control the speed and direction of the model (initially used on the MEC1 of 1965 and subsequently applied to the TE in 1967), whereas the TE1 was uni-directional only with an exhaust "choke" to control the speed. The TE1 was claimed to cover a third of a mile in ten minutes on a single filling.drive band running from a small pulley on the flywheel to the rim of one of the back wheels. This can be removed to allow the engine to run stationary or to drive a lineshaft and tools. The front axle of the model is mounted on a central pivot with a simple copper stub spring, which provides a crude form of suspension. It is also steerable, by means of a shaft running from the axle up inside the chimney (later models post 67). Early models did not use the later control rod for steering but used a rod mounted directly into a hole in the early model square axle box. Both designs could be screwed down to lock the wheels in a fixed position. A control rod, with a wooden handle on top, can be attached to the top of this shaft to allow the operator to steer the model as it moves. The TE1/A has a green boiler (this green has varied over the years from apple green to a dark brunswick green, similar to GWR locomotives), red spoked wheels and flywheel, a white/cream coloured canopy and a black firebox/smokebox/chimney. It is also available in a distinctive alternative paint scheme, with a polished brass boiler and maroon wheels. Other limited edition models have been produced in the last decade using blue or black paintwork, as well of variations of the colours mentioned already.

The "Centurion" is a larger, more powerful version of the TE1A model, but fitted with Mamod"s piston valve engine (as used on the SP6–SP8 engines). In other respects it is the same as the earlier model, with the same layout and green/red colour scheme.

This is a model of a two-seater roadster style car, possibly based on the look and style of a Mercer Raceabout from the early 20th century. The model first appeared in late 1976 and was designed by Steve Malins with input from George Morris. The first versions were finished in red and white with black upholstery (still available) although newer versions have recently appeared with green/brass or burgundy/brass finishes. A silver 4-seater limousine, based on the Roadster, is also a popular model appearing in the 1980s. The boiler cover forms the "bonnet" of the car with the sight-glass for checking the water level being the "radiator grille". Early versions sported the traditional overflow plug, which was replaced by the sight glass in 1978 to conform with the new Euro Toy Regulations. The earliest Roadsters were meths fired, appearing in late 1976. From about 1977, all models used a steel pan-type solid fuel burner, although the older steel pan meths burners still fitted. The oscillating-cylinder engine is mounted externally on the left-hand side of the model and incorporates a simple forward and reverse lever like that used on the SE2a and MEC1 stationary engines. The unit drives (via a shaft) a small solid flywheel, mounted externally on the right-hand side. Again, a distinguishing feature of early models is the "split-drive" with final drive on the left-hand side, as opposed to later (and current) models where the drive is all on the right. This shaft drives the rear axle by a power band. This arrangement allows a slightly higher road speed than the SW1 wagon, but makes the model much slower than the TE1 traction engine (which was ridiculously too fast). This chassis and layout is used on other mobiles in the Mamod ranges such as the LB1 London "bus, FE1 fire engine, SA1L limousine as well as the DV1/2 vans. The early wheels are in the style of wooden carriage wheels (as found on cars of the period – these were known as artillery wheels), with solid rubber tyres. Later models used a re-designed wheel which was based upon the design used for the Rolls-Royce Silver Ghost. Details such as running boards, spare wheel and carriage lamps are also fitted.

This model represents a typical British light commercial vehicle of the interwar period. It has an enclosed rear body with twin rear-opening doors and an open driving position. It is painted dark green (DV1) or dark blue (DV2) with brass detailing and carries a Mamod livery.

This model represents a typical Edwardian or interwar 2-seat racing car used for long distance races such as the Le Mans 24 Hour Race. Whilst using the same basic chassis and layout as the Roadster and Limo, it has a two-cylinder uni-directional engine, with external cylinders on each side of the chassis to provide more power. It has an open "cockpit" with an aerodynamic sloped rear end. It is painted with either red or blue (and two off in Green, very rare) bodywork, including fenders and wheels, with a chrome boiler cowl. It carries the racing number "12". Although the model uses the same running gear and pistons as the other engines in the range, it is actually the fastest in the mobile Mamod lineup. This particular model is suitable for a radio control receiver to be fitted, to control the steering mechanism.

Introduced in 1989 as the flagship of the Mamod Mobile Range, the London Bus is based on an early double-decker design such as the LGOC X-type. It carries the livery of the London General Omnibus Company and carried Mamod adverts in the style of the Edwardian period. It has red bodywork and black wheels, shares the distinctive spoked rear wheels with the Steam Wagon model (see above) and has an open top deck with an open rear staircase. It is available also in a green livery.

These two models were commercially unsuccessful and were only produced for a short time. The Meteor was a steam-powered boat in the style of a Second World War torpedo boat and sold about 1,500 units. The Conqueror was an electrically powered version of the Meteor using a FROG Revmaster motor. Both models used the same hull which was of all steel construction. The Meteor used a single cylinder engine similar to the ME1. The Conqueror used a battery instead, with a slight re-designed inner hull accommodating the 4 D type cells in a metal holder. The motor itself drove the stern tube prop-shaft by means of a spring steel belt and pulley. It was Mamod"s only venture into electrical power but was even less successful than the Meteor, selling about 200 units for the same price as the steam version. Both models were dropped in 1952, making them much sought after by collectors.

Despite the failure of the Mamod Meteor and Conqueror boats (1949–52) Malins Engineers introduced the ME1 (similar to the pre-war ME1 but with a vapourising spirit lamp) and the ME2 in 1958.

The ME2 was introduced in 1958 at the same time as the ME1. Dimensions of this engine are the same as the ME3, except that it had a Mamod upright engine as opposed to the SEL upright engine used in the ME3. The ME2 was not particularly successful and was replaced by the ME3 in 1965. The fact that the ME1 represented a complete engine unit, whilst the ME2 basically was the boiler and engine unit probably worked against their success.

The ME3 was basically similar to the ME2 equipped with a heavier duty engine unit (an SEL 1560 Steam Launch Unit) designed to turn a bigger propeller. The unit used the ME1 boiler but, with a stroke of ½ in (12.5 mm) and a bore of 7/16 in (11 mm), the engine could drive a 1.5 in (38 mm) diameter three-bladed propeller through a dogged pulley arrangement – as opposed to the stern tube system used by the ME1. Like most of the marine engines made by Mamod, the SEL engine lacked a lubricator and needed careful setting up to work correctly. The ME3 was in production from 1965 to 1972, by which time (and after 2,700 units) all the SEL engines that Malins Engineers had purchased at a knock-down price from J & L Randall (parent of the SEL brand) had been used up.

In late 1979 Mamod introduced its first model railway, the O gauge live steam SL-1 locomotive, along with a small range of rolling stock and track. The model was of a narrow gauge railway and, although it was not based on a specific prototype, it was to approximately 16 mm scale, thus representing approximately a 2 ft (610 mm) gauge railway.

The Mamod Steam Railway, as it was known, was the first cheap, mass-produced live steam set in the United Kingdom and it sold well. Mamod quickly increased the range with further locomotives, the SL-2 and SL-3, available in ready-to-run and kit-form and in both O (32 mm) and 1 (45 mm) gauges. The locomotives used a pair of double acting, oscillating cylinders connected to a rotary reversing valve. This, in theory, allowed the locos to run slowly, and to "self start". Special edition locomotives, further rolling stock and points were also made. The current range consists of re-designed versions, although still in the same basic configuration. Many upgrades, both mechanical and cosmetic, are available to upgrade Mamod locomotives.

MSS (Mamod Sales and Services) continues to manufacture and sell the basic locomotive and stock, as well as a new saddle tank model introduced in 2004.

In addition, the basic design of the Mamod has inspired several improved versions supplied by independent manufacturers. Notable amongst there are the Creekside Forge & Foundry Baldwin, the PPS Janet and the IP Engineering Jane. Several manufacturers also supply upgraded components for the original Mamod line. A particularly popular upgrade was to fit the locomotive with a Methylated spirit burner which produced greater heat and therefore allowed higher boiler pressure and greater hauling capacity.

The company went into receivership in 1980, mainly due to the fact that the financial outlay both on the SP series of engine and the new RS1 and RS2 railway sets had been considerable. Many companies in the early 1980s were experiencing financial difficulties, and banks were calling in loans and finance agreements at the time because of the economic downturn. Malins Engineers" bank asked Malins to repay some of the money, giving the company the weekend to raise the cash. The company was unable to raise the money and so went into administration, though it was trading in the black within a few weeks, with the new railway sets selling well. Eric Malins, the Managing Director and Steve Malins, his son, gave up control of the company, thus effectively ending the Malins" family relationship with Mamod.

The large number and low cost of Mamod models means they are still popular today. There is a thriving market in spare and replacement parts from a variety of small manufacturers. Second-hand models are cheap and readily available and are often used as the basis for conversions by modellers.

Most Mamod engines lack lubricators to store oil and feed it to moving parts, such as the piston and bearings. The very early pre-war engines such as the SE3/4 and some of the marine engines (including the Meteor boat) were the only ones to have them. Instead, oil is applied manually to the necessary parts before each run.

Up until 1976/77 all Mamod engines used methylated spirits (known as "denatured alcohol" in some countries), which was either stored in a reservoir burner or vaporising spirit lamp. With the introduction of stricter health and safety laws and the European Toy regulations, the use of liquid fuel for use in steam toys in the UK was outlawed from 1977. Malins decided to switch to solid fuel after the infamous "exploding fuel lamp" story of 1976Hexamine fuel tablet in redesigned burner trays which, at the time, Malins manufactured on their own premises. The solid fuel is, in some respects, much safer than "meths". While burning, however, it gives off unpleasant and toxic fumes and a reduced level of heat. New models are now designed to use butane gas burners. This is likely to become the norm following restrictions on posting (mailing) flammable substances, including solid fuel tablets. Butane gas is easily available in DIY stores.

In 1980, the Mamod Company, which had been making toy steam engines since 1939, produced its first locomotive. This was a tiny 0-4-0T, nominally in 16mm scale, to run on gauge-0 track. It had a pair of double-acting oscillating cylinders, a soft-soldered boiler, a lever that controlled both speed and direction, and an unsatisfactory solid-pellet firing system. It was cute, cheap, and an instant success, despite its drawbacks. Indeed, these drawbacks spawned any number of cottage industries that produced a wide variety of products to overcome them. Over 18,000 of these engines were made before production of the original locomotive ceased in 1989. Because of its basic design and simple constructions, it lent itself readily to kitbashing, and thousands of modified Mamods are still on the tracks today.

Today, Mamod Steam Models, a descendant of the original company, has introduced a new and improved version of the original Mamod locomotive. This engine shares some of the features of the original, including a sight glass in the cab, a reversing lever on the pilot deck, a pair of double-acting oscillating cylinders, and riveted, sheet-metal body work. Beyond these superficial similarities, it is a completely different locomotive.

The new Mamod engine sports glands on the cylinders, significantly improving their efficiency. It has a larger, higher pressure, silver-soldered boiler with a pair of water tubes that extend into the fire space below to increase efficiency, and a safety valve that blows of at 40 psi, instead of the original’s 10 psi. This makes the locomotive a stronger puller. The lever at the front end controls direction only-there’s a proper throttle in the cab to control speed. Our review sample is 0 gauge; the company offers parts to easily convert the engine to gauge 1.

Preparing the engine for a run is straightforward. The gas tank is removed, filled, and replaced, as mentioned above. The safety valve is removed and water is added to the boiler up to the maximum-fill point on the glass. The engine’s moving parts are lubricated, and it’s ready to go. This engine is not equipped with a cylinder lubricator. You pull the cylinders away from their port faces and add a drop or two of oil there, which is supposed to get into the cylinders to lubricate them. The original locomotive had no lubricator either. At its low operating pressure (and temperature), it relied on water in the cylinder for lubrication. Outside companies provided aftermarket lubricators for that engine, which worked to improve performance somewhat. This engine operates at a higher pressure and temperature and I think that a displacement lubricator, which would distribute proper steam oil to the cylinders, would be an asset and would increase the engine’s longevity.

To light the fire, I opened the gas valve a little until I heard a hissing sound (as per the instructions). The I applied a flame to the space between the boiler jacket and the frame. It caught immediately and I could see the blue glow of the fire atop the ceramic burner. The instructions say to let the engine warm up with the fire at its lowest setting for 30 seconds, at which time the valve can be opened a quarter turn. This I did. I prepared and lit the engine in my workshop. When I got outside into the bright light, I found it very difficult to see if the fire was lit.

The 20-25 psi valve is available in a 1/4 x 26 tpi thread for standard loco boiler, usually fitted in place of whistle when used with Water Top-up Valve.

If you require an alternate blow off pressure please add your request to the comments at the checkout and the valve will be set before dispatch. Currently the allowable range for custom setting is 20 to 60 psi.

I bought this after looking around the author"s website. I used to play around with Mamod engines long before I had children of my own and from what I remember I screwed a few of them up good and proper trying to "fix" them. Anyways I recently was bought a Steam Wagon as a gift from a flea market, and with two of my kids still at home we thought we would bring the thing up to working order.

MAMOD SAFETY VALVE "O " RINGS (top of safety valve only) (FIVE). What people with a Mamod engine needed to get the. FIVE MAMOD STEAM ENGINE "O" RINGS. Tip: The "O" ring/ washer is fitted by rolling it over the round head of the shaft - persevere and be patient - it will go on. eBay template script "When I set up Model Enthusiasts in 2004 the idea was to find out what people with a Mamod engine needed to get the engine running as it should. That"s still true today and you can see our catalogue here . Trevor. eBay Tem[plate Page FIVE MAMOD STEAM ENGINE "O" RINGS FIT ONE UNDER THE TOP DOME (IT DOES FIT!) FOR THE 1/4 INCH SAFETY VALVE This Safety Valve is not included in the sale! Right for your Traction Engine and the Steam Roller - and others. Tip: The "O" ring/ washer is fitted by rolling it over the round head of the shaft - persevere and be patient - it will go on. But do not use anything sharp as the ring will break before it is fitted - it works if you use your finger nails though. You may find it helpful to use a soapy solution to ease it on. This set is also suitable for Mamod SE3 steam engines or any using a 3/8th inch diameter Safety Valve. It"s just harder to fit over the larger dome.

Off topic, however, is there actually any need for running at 60psi? Lets face it, anything above 40 and the Mamods can"t really put the power down. If you are hauling a train that requires 60psi then you"ll more likely loose grip before you can actually run the train at any decent speed, so thus you"ll end up running the train with wheels spinning and adding additional wear to the loco. In the end you"ll be running a train which will be rather ridiculous for running at 60psi as it doesn"t need all that power as it can only really convert it to speed.

Off topic, however, is there actually any need for running at 60psi? Lets face it, anything above 40 and the Mamods can"t really put the power down. If you are hauling a train that requires 60psi then you"ll more likely loose grip before you can actually run the train at any decent speed, so thus you"ll end up running the train with wheels spinning and adding additional wear to the loco. In the end you"ll be running a train which will be rather ridiculous for running at 60psi as it doesn"t need all that power as it can only really convert it to speed.

Above 40 psi? My Titan (dream steam works loco from Alan at PPS days) cannot get the power down at 40. I don"t see the point at running at 40 psi! I was thinking of knocking the SV back to 30 or even 25, 60 psi is just pointless. You are putting unnecessary stress on all parts involved!  In my experience a higher pressure makes slow running harder to do and you have to uprate every spring and working surface to even try. My Chevalier runs at 10-12 psi and runs like a Swiss watch on that, even with standard Mamod cylinders and pulls a modest load too. I can imagine that she would be blowing steam out of every orifice if 60 were involved, who runs at 60 psi ffs? My Roundhouse Billy runs at 30 psi and that can pull the house down, totally different model I know.

Doug, I was not having a go about your running pressures, I didn"t know you did run at 40 - 50 psi and was not attacking you directly. What I was alluding to was the fact that yes a Mamod gene pool model may function at 60 psi all day long, what is the point in doing so when 40 psi is more than plenty in my experience. Yes Chevalier is brass boilered and meths fired, should it make a difference to how efficient, well and smooth she runs with standard parts and near on standard operating pressure? If anything it should be an achilles heel. If I wound the safety valve in, Chevalier can run like an absolute idiot if I allow it at 30 psi, really that is credit to the running gear of the model.

Doug, I was not having a go about your running pressures, I didn"t know you did run at 40 - 50 psi and was not attacking you directly. What I was alluding to was the fact that yes a Mamod gene pool model may function at 60 psi all day long, what is the point in doing so when 40 psi is more than plenty in my experience.

Yes Chevalier is brass boilered and meths fired, should it make a difference to how efficient, well and smooth she runs with standard parts and near on standard operating pressure? If anything it should be an achilles heel. If I wound the safety valve in, Chevalier can run like an absolute idiot if I allow it at 30 psi, really that is credit to the running gear of the model.

Oui. For the most part - 60psi would be a special occasion but rarely used. 40psi on a good day will do fine. Anything over 60 as has been seen is gas off, open reg, add water to dampen it down as one is conscious of safety and surroundings.

I"d say this thread was necessary as its a topic that can have an effect on Mss/Mamods/Janets/Janes/Etc... But too much pressure e.g 40 upwards is just silly as it will just make them speed demons and more accident prone thus tarnishing the good reputation that other mamod type loco owners who are careful, be it Meths or Gas, have.

"As to running upgraded Mamod type locos at 60 PSI each to their own I guess. I quite happy running my various Mamod type locos at up to 40 PSI, and the Cheddar Iver & Cheddar/GRS Tram which use a similar sized oscillating cylinder (as their cylinders are no longer available as spares you can replace them with the upgraded Mamod type ones quite easily) are designed to run at 45 PSI (max operating 60 PSI) and are significantly heaver (they will continue to slide along for a bit after you have stopped the wheels turning, which you need to factor in to your driving technique)."

Another useless piece of trivia. Although one set of my Dream Steam steel wheels have a larger diameter outer part on the flange (the bit that contacts Mamod combustion chambers) the part of the flange that is actually in contact with the railhead is just smaller in diameter than the corresponding part of the flange on standard Mamod/MSS wheels. The wheels on the much heavier Cheddar models (effectively using the same size cylinders) are much bigger in diameter having no combustion chamber restricting their size.

Why the hell is anyone having a go at you? People are here freely conversing about the operating pressures on Mamod gene pool locos, its not all about you Doug... As for you to explain anything about operating pressures to me, I have my opinions, you have yours and I am sticking to mine.

dougrail:91613 wrote:Oui. For the most part - 60psi would be a special occasion but rarely used. 40psi on a good day will do fine. Anything over 60 as has been seen is gas off, open reg, add water to dampen it down as one is conscious of safety and surroundings.

MAMOD LIVE STEAM MODEL TRACTION ENGINE TOY Length: 11 inches (27.9 cm) Provenance: Private Collection 1998. Museum - Available at 2014 May 28 The Glenn Reid...