The Mamod Royal Family of Steam Locomotives.

[Chris Cairns]

In 1989 the original Mamod Steam Railway Company range ceased production, and Mamod were up for sale again.

In 1990 Mamod Limited was acquired by Adam Leisure Group PLC and production moved to Blaydon, near Newcastle upon Tyne. The railway system did not feature in Adam's plans for Mamod so many of the tools were not transferred to the North East. In 1991 Adam Leisure Group PLC was taken over by Porter Chadburn PLC and again Mamod was up for sale in 1992. It was bought by Thomas Johnson & Company, who previously supplied pressings to Mamod and is run by the Terry family, and it moved back to Birmingham. It is said (by David Evan's MSS) that the railway system did not feature in Thomas Johnson's plans for Mamod either, but David Terry has confirmed earlier this year that there was no railway system assets available during the sale. This caused a dispute between MSS (then Mamod Sales & Services) & Mamod in the late 1990s after MSS starting producing rebranded Mamod SL locos.

So the current Mamod introduced a revived Mamod Steam Railway Company, introducing the track first. Their 1st loco, the Golden Jubilee, was due out in 2003, but difficulties with the prototypes lead to a design change so it did not appear until 2004.



1355 Golden Jubilee Loco SL1



So the original design used a modified Traction Engine Smokebox casting and boiler, fitted with a safety valve, working steam chest and whistle. This was to go through a radio controlled throttle assembly (servo in cab, rotary control on lubricator block between chassis) to feed steam through a set of rotary valves for the final drive. The rotary valves were changed for a slide slip eccentric valve, the radio control was dropped due to cost, the boiler lost its smokebox casting, working steam chest and whistle, to be replaced with a boiler mounted regulator control.


This is copyright of steamyjim who appears to have vanished on-line recently, but shows the early prototypes.

A none-working static display Sales Model was sent out by Mamod to Forest Classics, and strangely had different markings on either side tank.

Eventually the re-designed slip eccentric Golden Jubilee loco was released in 2004.



As seems to be the way with the current Mamod production got ahead of the prototype so the cabs still had the cut-out for the whistle, and the cab floor had the cut-out for the throttle control.


The cut-out for the throttle control which was dropped before production.



So the purple box (and we will see these again with future Family members) just has 'O' Gauge Steam Locomotive as its title, with a note 'Celebrating the Queens Golden Jubilee Year'. No mention of SL1 as per the 2004 brochure entry.



It was supplied with L71 Operating Instructions leaflet, L90 General Warnings leaflet, a 2004 World of Mamod brochure with the revised Golden Jubilee Loco on the cover, and a Limited Edition certificate.


The Limited Edition certificate for my Jubilee No.067, but note the strange loco at the bottom.


An none-working original rotary valve prototype - there is no connection between the valves and the wheels!

By No.103 that loco on the certificate had changed! (someone is still trying to flog this loco for some ridiculous price on ebay every now and then).





The loco came with a bottle of steam compound oil and a funnel.





It was my intention to take this loco apart for comparision with future members of this 'Royal Family', but as the front rivet holding the engraved numbered plaque is up against the burner, and the gas tank is badly deforming the cab sides I will leave it alone as it is for collection purposes only.



Here you can see the cab sides are not fixed to the rear of the loco and the gas tank has been mounted too far outboard and is bending the cab side outwards (we will meet this poor quality control with a future family member again).



The underside of the chassis showing the rotary plug that has been fitted into the block where the throttle control was to have been fitted just forward of the steam pipe entry point.



The gas burner which was to cause many of these Jubilee locos to be permanently heat damaged - see here for an example - http://modelsteam.myfreeforum.org/viewt ... 58&start=0



And the only bit of the loco that lets you know it is a Golden Jubilee is the engraved number plaque under the cab on the left side.

The loco was provided with toy couplings which were only to be compatible (and even then there was problems) with the toy rolling stock that Mamod produced from 2004. They used a triangular plate at the front with a circular hole, and another triangular plate at the rear which had a vertical prong. Unfortunately these plates are at the same height so you ended up raising either the loco or the rolling stock, and this could lead to derailments particularly through the points. Some work was needed in bending those plates plus reducing the sides of the vertical prong to make a better coupling connection. It is not really compatible with the old Mamod & current MSS oval coupling rings.

It is not known if all 500 locos were sold (a few were made in 45mm gauge), but Mamod expected a lot from this loco as the over production of parts including those purple boxes will feature in future family members.

Stayed tuned for more family members (another 3 so far).

Chris Cairns.

[Chris Cairns]

So the Golden Jubilee locomotive introduced the first slip eccentric piston/cylinder assembly to the Mamod range, which was then used in the SP6 & Special Order only SP7 Stationary Engines, plus a few of the Mobile Engines. It also introduced the first ceramic gas fired engine to the Mamod range, and whilst that has still not been added to the Stationary Engines, several of the Mobile engines are now gas fired.

According to the instructions the Golden Jubilee boiler is soft soldered.

So following on from the apparent success of this engine Mamod introduced the next engine in the Royal Family of Steam Locomotives range in late 2005.

1355W Loco SL1 William



Remember those purple boxes used with the Jubilee loco. Well here they are again with a "William" "O" Gauge coloured sheet stuck on top. Again no mention of SL1 as listed in the 2006 brochure entry.



It was supplied with L71 Operating Instructions leaflet, L90 General Warnings leaflet, and a 2006 World of Mamod brochure with the new slip eccentric SP6 Stationary engine on the cover.

However ths was my first experience of the Mamod policy of continual product improvement, in other words, you do not get what is on the tin (box!).



Instead of a green William with white Working Steam Models transfers I got a slightly darker green William with Mamod 1936 stick on badges. In fact, after I removed the protective covering from these badges they have stood up to the excessive heat generated by the burner & combustion chamber combination better than the stick on white transfers which would have melted/burnt by now. It is also supplied with steam compound oil and a funnel.



Essentially this looks like a repainted Jubilee, leading one to suspect that the story of Jubilee production parts overrun may not be true (I've seen photos of a green William which was dissected on-line and the heat had burnt the side tank paint to reveal red underneath) , but there are a few changes.

The boiler is now silver soldered and painted with a ripple effect black paint, the regulator control now has a brass wheel which is fitted with an 'O' ring around the outside (the previous plastic ones tend to melt and work loose), the brass coloured wheels ran out so it is now supplied with black wheels, a hole for a gas can adapter has been made in the cab roof (took a while for this to be standard on all locos) and the rear buffer beam plate has been extended so that the cab sides are now secured by rivets.

What has not changed is the cut-outs in the cab front & cab floor.









They also put a heat sleeve around the nylon gas pipe inside the chassis but that sleeve is not flame proof and will catch fire from stray flames.

I'll readily admit I was not impressed with this loco's initial performance (and another example of poor quality control will partly explain why) but after a fair bit of work I got it to be a better runner.

I'll now need to dismantle this loco so I can explain the problems I suffered in the next part of this Topic.

Chris Cairns.

[Chris Cairns]

1355W Loco SL1 William (cont'd)

Found an old video on Photobucket which is rather amateurish with my old camera and of course had its resolution very compressed by Photobucket but thought it worth posting here as I no longer have the original files (departed with another hard drive failure).

<embed width="600" height="361" type="application/x-shockwave-flash" allowFullscreen="true" allowNetworking="all" wmode="transparent" src="http://static.photobucket.com/player.swf" flashvars="file=http%3A%2F%2Fvid179.photobucket.com%2Falbums%2Fw283%2FCCairns_2007%2FMamod%2520Steam%2520Railway%2520Company%2FLocomotives%2FWilliam%2FMamodWilliam01_0002.mp4">

So to the problems with this William (apply equally to the Jubilee).

1. Gas Burner. This is too big for this loco and it is easy to turn up the burner too much either getting flames licking over the top of the boiler (indicating it may be running a bit rich due to airflow problems) or flames coming out the side burning the chassis and bottom of the side tanks. I mark the gas valve with a line so I know how much I'm using.



The problem with the airflow is due to the design of the combustion chamber. This is just 2 vertical metal plates which are riveted to the chassis. They are neither curved nor semi-hexagonal shaped, so restrict the airflow going up around the boiler. This leads to the whole chassis being heated up by conduction, and in particular the gas tank. This is held to the front of the cab by a metal clip and rests on the cab floor. As the tanks heats up the gas starts to pulse leading to an erratic burner. To reduce this heating effect (can happen on other gas fired Mamods as well) I now wrap the gas tank body with masking tape to stop the metal clip digging into the body, and put a felt pad (those you get for furniture on laminate flooring) on the bottom of the tank. This seems to stop this pulsing. The slot in the top of the side tanks is also very small further restricting the airflow coming out over the boiler.

Another problem with the burner is the jet holder. This is a very loose fit inside the burner tube allowing air to get in. When I've had problems with the burner pulsing I have had the odd blow back where the flames have ended up setting fire to the gas tube heat cover! To reduce this sloopy fit I wrap PTFE tape around the gas jet holder so it is a snug fit going into the burner tube - I guess using some form of heat resistant sealer would work as well.

And the exhaust steam also seems to affect the burner occasionally. This comes out the bottom of the valve block straight onto the track.

2. Motion. The wheel axles are held in bearings which are free to rotate in the chassis, and also have sufficient play to slide in and out horizontally. Mamod's answer to this is to Loctite the bearings in place but that is very difficult to achieve without locking up something else as well, particularly as the rear axle has the eccentric strap behind the wheels. I also tried soldering these bearings in place without success. Would need the chassis de-riveting and then the bearings held in place with Araldite Rapid Steel as I've done on my MSS Loco build.



The eccentric strap and couplings rods are made of a very soft metal so these are easy to bend and can foul up on the wheels locking them up as has happened on my William.

Another answer from Mamod is to use thicker gaskets on the valve and cylinder blocks so as to bring the piston rod further out from the wheels. I had to do this on one side of my William to stop the coupling rods fouling.



Not very clear with my overhead lighting but there is rubbing marks on the coupling rod which has been rubbing against the rear wheel, and the eccentric strap has been rubbing against the front wheel.

3. Lubrication. Mamod have some strange designs for lubricators, with the ones on the Brunel & Mark 2 Locomotive's as examples. Not exactly sure of the routing of the steam through the block between the chassis frames but the one fitted to this William would appear to be a variation of a dead leg lubricator. In use I found this one used up the oil very quickly but that now may be due to filling it up too much. This loco (and my William II) suffer from a strange burst of speed increase occasionally whilst running around my oval of track. Initially I took this to be the 'O' ring on the regulator leaking but having changed those I am now of the opinion it is when some oil is pushed through to the piston freeing it up momentarily.

The piston and piston rod are shaped from a solid piece of metal and the piston has a very small oil ring cut into it. Being one piece this has lead to some problems with steam leaking out of the rear piston gland face (we will meet this again on the William II).

So on my William II what I now do is fill the bottom lubricator cup full of steam oil and replace it into the block. Through the top hole I add some more steam oil till it just touches the steam pipe. I then raise steam and open the regulator to clear any emulsified oil out of the lubricator steam pipe until it runs clear, then close the regulator, replace the top lubricator cup, and start running the loco as normal.

It was certainly discussed on-line at the time that the capacity of the William lubricator needed increasing. I now wonder if fillng the lubricator as above and to a slightly smaller level will make any difference.

(edit) 4. Quality Control. I found an old photo to explain the quality control problem I suffered with this loco. It was taken with my old camera that would not focus down to macro but I think it still illustrates the point.



Going back through my old postings I remembered I had talked about my initial poor running of this loco which had a very strange squeaking sound and ran out of steam quite early. After taking the loco apart it turned out that a brass washer had been trapped between the valve block & the cylinder block on one side of the loco (Point D in the photo, and if you look at the previous photo above this one with the blocks dismantled you can still just see the outline of that washer in the gasket), thus there was a constant steam leak. After removing the washer the loco's performance improved and it eventually was run in properly continuing to run until the water got low (those gas tanks are too big so boiler water runs out before gas).

Here's a photo from June 2006 which shows Mamod's future plans for the new Mark 1 Locomotive must have started back then.



This is a William Train Set which was being marketed in 2006. Note that the wheels fitted to the Open wagon & Guards van are the same as those currently fitted to the new Mark 1 & 2 locomotives.


So the next member of this Royal Family is Mamod's finest creation and a very sought after model - Oh really!!

Chris Cairns.

(edited to add an old photo to explain a problem with Quality Control).

[Chris Cairns]

So Mamod's finest creation was produced in 2006.

1355H Harry the Rocket '1' Gauge



The only surviving image of the original format Harry the Rocket, which is one of those very small images that Mamod used scaled up slightly.

I know that when Harry was first marketed it caused quite a stir in the on-line community but no-one actually 'bit the bullet' and bought one, or at least admited they had! So if you are going to ask the age old question 'What were Mamod thinking?' then I'll politely reply 'Please ask Mamod as they made them'.

In this format it looks to have been made from a modified Traction Engine smokebox casting, a boiler with safety valve, steam chest (working?) plus something in the rear boiler outlet. 2 single acting cylinders connected by short cranks to the wheels, and gas fired. From my experience with single acting cylinders on Bowman locomotives I guess it would have run at a very fast speed without a regulator being gas fired and is probably why it developed into a belt driven model instead.



Still got some of those purple Jubilee boxes to use so we best stick a Harry the Rocket coloured sheet on top. A total of 50 were made but it is unclear if they were all sold. I've seen the incomplete prototype now in an enthusiast's collection, and pauly on this Forum has one in his collection as well.



It was supplied with an Operating Instructions leaflet, L90 General Warnings leaflet, application form for the Mamod Collectors' club, and a 2006 World of Mamod brochure with the new SP6 on the cover.



It was supplied with lubricating oil and a funnel.



It was suggested that this was made from the spare parts box and that is generally true. It uses a modified Traction Engine boiler with the empty void at the front of the boiler, a false chimney from the Jubilee/William locos which has a hole going into that void at the front of the boiler but this does not affect the pressure vessel part of the boiler (i.e. you can steam it up with that hole as it will not leak).



Various theories were put about what wheels were used. In fact they are all reworked Flywheels. So an FW3 is fitted to the top driveshaft, 2 reworked FW3s are fitted as the front wheels (the LHS one is fixed to the axle by a grub screw), and 2 reworked FW2s are fitted as the rear wheels.



A ceramic gas burner from the Jubilee/William loco is fitted with a smaller capacity tank.



A single acting cylinder and engine frame is fitted from a Traction Engine, with a larger flywheel, and this uses a drive belt to a special drive wheel fitted to the front axle.



The chassis and boiler casing is specifically made for this loco but strangely there is only a coupling hook point on the front of the loco (it only goes forward!).



Chasteam used to quote that it was available in Gauge 'O' but after I questioned that fact he removed it from his website. Although it would be possible to cut the spacers on the rear wheels to set them for 32mm, the front wheels would foul the boiler at 32mm so the boiler would need to be raised. Given their rarity I'm not going to cut mine up to see if it works in 32mm!





You will no doubt have seen the YouTube video of a Harry actually running - http://www.youtube.com/watch?v=yYT7cRxf7g4 As I recall it was reported that the wheel flanges had been improved slightly, a different drive belt system was used (looks to be a toothed belt), and of course it is running around a very large circuit with nice wide curves and no points.

Still it proves that it does work.


So one more member of the Royal Family to be introduced. But as that came in a very large box I'm not sure how I'm going to get a photograph or two.

Stay Tuned!

Chris Cairns.

[Chris Cairns]

If you have already been viewing this Topic please go back up to the 3rd posting (2nd on William) where I have added an old photo which illustrates the poor quality control I experienced with that loco.

So the next engine in the Royal Family of Steam Locomotives was introduced in 2008.

1355W LOCO SL1 William II

This is the photo that Mamod and other traders use for the William II.



Note that they have gone back to fitting a plastic wheel on the regulator.

Specification as per the original William with improved cylinders, burner & other detailing.

I was intrigued as to what the changes were that Mamod made and how much this improved the loco compared with the original William. However the price put me off, and no-one else on-line was admitting to owning one. Eventually when the William II Train Set appeared at an attractive price on-line from a trader I decided to get one so I could compare this loco and add the new rolling stock to my collection.





It would appear that Mamod were having a stock room clear out, as they no longer sell this train set. In mine the Guards Van is not Dual Gauge and looks like a Friday afternoon special with several extra holes in the chassis, and the bodywork is held together by spot welding and not rivets. These are still being sold by Chasteam at £560, or if you wish better customer support then Forest Classics have them at £800- I'm sorry how much!!!!



They were supplied with L71 Operating Instructions leaflet including an extra sheet on Fuel Tank Filling & Gas Control (Mamod's printed solution to irregular burn patterns is it may be due to a blocked jet - we shall learn otherwise shortly), L90 General Warnings leaflet, a Track Assembly Information leaflet, a World of Mamod 2010 brochure which has the William II on the cover (but the William II or the track are not listed inside), a bottle of steam compound oil, a bottle of lubricating oil, an EN437 gas adaptor and a funnel.



Again this was another case of 'what you get is not what is on the tin (box)' as my William II had those stick on white transfers instead, plus a brass wheel with outer 'O' ring regulator (the brass chimney cover is part of my ongoing makeover). And the Rolling Stock in the cover photo is not Dual Gauge either.

So let us look at those improvments.

1. Improved Cylinders.



So Mamod said they were introducing a 'floating piston' when enthusiasts got back to them concerning the poor running of the William loco. No-one found out what this 'floating piston' actually is but the one on my William II has no grooved oil ring. The rear piston gland has been improved (just like the New Mark I & II locos) with an 'O' ring to seal the piston rod and a 2nd 'O' ring to seal the screw in gland. The block has also been machined to remove some of the excess metal, presumably to keep it cooler, and the valve block now has 2 exhaust steam ports. When I questioned this with Mamod as fitted to their Brunel I was told it was to improve lubrication. Disadvantage it has is the exhaust steam from the top runs down the sloped valve/cylinder block and then washes out the piston rod.



They have also cut back the running board on the chassis although I suspect this was more for the benefit of the burner.

2. Improved Burner. So they have modified the burner fitted.





The top burner in each photo is from the William with the bottom burner from the William II. So although they are using the same ceramic material it does not extend upwards as much in the William II burner and the front mounting of the burner has had the upper & lower portions shaved flat (cannot see what benefit that will have).



With the cut-out to the running board of the chassis the bottom of the side tanks has been raised allowing more air to the combustion chamber which now has 4 holes drilled in the vertical plate.

However when I first started running this loco I suffered some permanent heat damage from the burner. It burnt the paint on the chassis and bottom of the side tank, plus badly melted the plastic stick on transfer on the left side.





This was due to another example of poor qualty control. When the loco was assembled they managed to trap the vertical plate of the left side combustion chamber inside of the rivet used to mount the gas tank bracket to the cab front. This restricted the airflow over the boiler leading to that massive flare up sideways.





So whilst they have used a similar style to the Mark I & II locos they still insist on using a vertical plate for the combustion chamber. On the Mark I & II locos the plate has been bent twice so is semi-hexagonal shaped which allows the air to flow better around the boiler. On my Mark I & II locos the plastic stickers have not melted so far, unlike this William II where I've been left with some stuck on residue which will not come off with rubbing compound, white spirits, etc.

3. Other Detailing. Not sure what this means other than the change to the running boards and side tanks as mentioned above. My William II is a 2010 model which has 2 re-heat tubes fitted to the bottom of the boiler, just like the Mark I & II locos - however I cannot be sure if they were fitted to the original 2008 William IIs.

So it seems Mamod have still not got it right with the William II. For the William III they should fit the Mark II combustion chamber, plus the cab sighted regulator as well. And a better lubricator with a larger capacity is needed but they never got that right on the Mark II either.

Sorry if you have already partly read this posting. Myfreeforums timed me out whilst editing and then of course Photobucket decided to freeze again so I had to submit twice and then re-edit.

This is the end of my Royal Family collection, but I forgot about the latest edition to this family by Mamod. However as no-one has got one it will just need to be a quick discussion posting instead.

Chris Chris.

[Chris Cairns]

And so to close this Royal Family of Steam Locomotives we go back to the original member as she celebrates another milestone.

Diamond Jubilee Saddle Tank.

This has previously been discussed on this Forum.



Mamod took their successful Mark II locomotive and replaced the side tanks with a saddle tank.



The front mounting plate has been curved although look how close it gets at the top of the boiler.



It is supplied with another stick on plastic transfer for you to melt.



And it looks like there is a similar curved plate fitted at the back to which the saddle tank is riveted.

Having experience of an MSS Saddle Tank, plus all the above problems with the William & William II burners, I'm not convinced that they have left enough air space around the boiler and so you will end up melting the transfer plus that saddle tank is going to get very hot.

The Saddle Tank, transfers, numbered plaque and ruby paint will cost you another £31 on top of a Mark II loco. It is a limited edition of 100, available in Gauge 1 as well, and there is a matching ruby tender, or you can buy it as a Train Set. They have tried to sell at least 2 on evilbay without success.

Still not convinced the price is right to get one of these for my collection.


So there we have the Royal Family of Steam Locomotives. Would be nice to have any responses to this topic but I appreciate the problem is so few people actually have experience with any of these locomotives.

pauly has a Harry the Rocket which he has already said will not be steamed as it is for his collection, and benchmark had an early William (with brass coloured wheels) which he modified into 'Lady of the Lake', but it then was not really compatible with his Bumpington Railway so may have moved on.

Chris Cairns.

[williamfj]

Another candidate for the reference library me thinks, a very interesting thread. I do have to admit that I quite like 'Harry the Rocket' for Mamod's bravery/insanity if nothing else!

[Narrow Minded]

Another excellent, well detailed "warts & all" technical description. (It's a refreshing change when an obvious fan of a product is capable of keeping their eyes [and mind] open to the shortfalls!)

I can't remember who was making the comparison between the Diamond Jubilee saddle tank loco and the Roundhouse Bertie - I hope whoever it was has read and digested the relevant section of this thread

As for "Harry The Rocket", all I can say is that it would probably look fine on a railway based in Equestria (or Ponyland, or whatever they call it )

And yes, this has absolutely got to be another candidate for the "Reference Section"

[Chris Cairns]

I had forgotten about the Diamond Jubilee review (as I do not always log in), so just been reading through it again.

As far as I can see no-one was actually comparing this loco with the Bertie, it was mentioned that the pricing was close to the Roundhouse Basic range, and then Doug said he would be interested in a Bertie for that price (£330-£375).

Interesting to also read the comments about Mamod dying after the Malin's family control. Due to poor sales in 1978 & 1979 against the tooling costs required for the new 'SP' range and the Railway System, they ended up putting Mamod into receivership in 1980, despite an external accountants report recognising that the imminent production of the railway system would turn round the poor trading position. There was one small production problem which delayed the railway system by the crucial few weeks but that statement has never been fully explained. Ironically one of the first recipients of the new railway sets was the Bank Manager who sent in the receivers.

In fact Malin's were against engines in kit form, so it was David Evans with a later Mamod Ltd. who introduced kits to the Mamod range, including the much favoured SL1K in 1983.

I am sure the current Mamod would get more sales if they introduced kit versions of the current locos leading to a new generation of Mamodifications.

Chris Cairns.

[Annie]

Mamod NZ advertises the William at $NZ939.30 which means that they wouldn't want to hold their breath waiting for me to buy one.

The spec quoted on their webpage is just a bit mixed up too.

1355W0 - SL1 (W0) William '0' Gauge

Price: $939.30 Add to Order
Price in NZD including GST. Terms and Conditions apply.

Attractive locomotive in gauge '0'. Can be used with carriages.

A classic example of an early 0 4 0 Welsh side tank locomotive in 1 gauge. Forward and reverse controls, whistle, ideal garden railway. Powerful twin doubling acting arrangement. Walscherts valve gear, Corliss rotary valves. Max speed 19ft/sec, running time 15 minutes.

Technical Specification -
Bore: 9.5mm
Stroke: 14mm
Cylinders: 2
Valve Type: Piston
Valve Gear: Slip Eccentric
Boiler Capacity: Approx. 80mls
Operating Pressure: 1.13Bar (15psi)
Gas Capacity (max): 14.5c.c. LPG
Cylinder Lubrication: Displacement
Cylinder Oil: ISO460 compund T (recommended)

Pack Dimensions = 260 x 145 x 105mm
Pack Weight = 1.8kg

Stock Indication: Item not stocked locally
(Delivery approximately 2-4 weeks from payment.)

They are advertising the William trainset at $NZ1,638.10 as well which seems to be reasonable going by the prices they quote for the individual items in the set.

[Chris Cairns]

Annie,

Just been having a look at Mamod NZ. Nice to see that you have a dedicated outlet for Mamods in New Zealand but they are a bit out of date.

On their Home Page they have a photo of the Harry the Rocket, and if you go to the Steam Trains page, except for the solid fuel (and you do not use that with the gas fired William set but they include a box!!), everything else is Item not stocked locally. The William is no longer produced or available from any traders in the UK (only the William II), the William Set is no longer available from Mamod, although it is still for sale from Forest Classics or Chasteam (and Mamod NZ seems to have used photos from both of their websites).

Chris Cairns.

[andysleigh]

Great post chris!

I love seeing what prototypes mamod came up with, and how they changed.
Altho the one with rotary valves looks odd, id love to have seen one going.

Still room for lots of improvement on their newer models i think

[steamie1]

I loved my MSS Saddle tank Caradon, shot in garden rail again this month. Will the diamond jubillee get too hot with little top air venting. Or is it just better on the gas usage ie you turn it down alot??????Do tell if someone runs one, I really fancy one. Will it get discontinued soon????????
Thanks for all the info Chris I will read over and over I'm sure.
The suddern power spurts could well be oil sealing up the o rings giving a sudden burst?Thoughts only..
I still love the simple performance of the new Mk2 I'm on about 20 runs and it is really good. I get more fun and use from this little Mamod than my £1500 Roundhouse job!
Perhaps more is too much!

[pauly]

Another excellent, well detailed "warts & all" technical description. (It's a refreshing change when an obvious fan of a product is capable of keeping their eyes [and mind] open to the shortfalls!)

I can't remember who was making the comparison between the Diamond Jubilee saddle tank loco and the Roundhouse Bertie - I hope whoever it was has read and digested the relevant section of this thread

As for "Harry The Rocket", all I can say is that it would probably look fine on a railway based in Equestria (or Ponyland, or whatever they call it )

And yes, this has absolutely got to be another candidate for the "Reference Section"

ha ha funny man

yeah I actually have a Harry Rocket, I picked it up on Ebay for £100 its never been run because the gas tank leaks and has dented when Iv removed it from its holder
if I could get a replacement gas tank I would run it, yeah Id take it to steamups and run it stationary on a siding

I didnt know about the boiler void so I always thought mine was unsteamable and had perhaps been drilled to be used as a display engine in a shop

[dougrail]

Damn, shame about the gas tank. Could a RWM/DS/Bix-Forest Classics be used as a substitute?

[pauly]

Damn, shame about the gas tank. Could a RWM/DS/Bix-Forest Classics be used as a substitute?

probably but I dhave to get some measurments

[dougrail]

Well, the tank's physical size could be easy - build a support platform or something. My thought is the gas pipe connections, if they will match and seal or not.

[pauly]

Well, the tank's physical size could be easy - build a support platform or something. My thought is the gas pipe connections, if they will match and seal or not.

welll the Rockets are just cobbled together standard parts for the most part so I dont see why I wouldnt be able to connect another Mamod gas tank to that hideous plastic gas line

[dougrail]

True this! Perhaps you could contact Mamod and see if they could supply one direct?

[Chris Cairns]

Harry the Rocket uses the same size gas tank as the Mark I/Mark II/Saddle tank locomotives. However look at the price of gas tanks on their website - http://www.mamod.co.uk/product-category ... ccessories - £62!

Not actually checked the thread on the Mamod tank (probably 1/4" x 26 BSF) but I'm sure it is not compatible with the Bix 8 x 1 mm thread or the RWM one (not sure if that is 1/4" x 32 TPI or 1/4" x 40 TPI).

What is leaking on your gas tank - the refill valve (normally a new 'O' ring fixes that), the gas valve (again a new 'O' ring would fix that) or the gas pipe coupling (yet again another 'O' should fix that).

Chris Cairns.