Thomas Telford Locomotive - Take Two

Chris Cairns · Post by **Chris Cairns** » Sat Apr 13, 2013 10:25 pm

They seemed to be well on track for a Peterborough release though

If you have been following the regular updates from Mike it was obvious latterly that this was not going to be the case.

Have a look back at Mamod's history. The Golden Jubilee locomotive was advertised with the rotary corliss type valves in late 2002. However it never worked properly and had to be re-designed with piston valves (plus a few other parts were changed, including cancelling servo control on the regulator due to cost) leading to its release nearly 2 years later in 2004.

We have discussed the problems with the combustion chamber design and Mamod have changed that. We also discussed the problems with the burners and thanks to Mike's enquiries we have been advised of the design fault and how to correct it. We also know through Mike's enquiries that they are changing the loco's width & weight distribution to prevent tipping over on Mamod curves.

So it is all down again to another change of valve gear.

When I modified my William's burner the resultant increase in performance meant that I managed to achieve a continuous run at a realistic slow speed. This proves the piston valve gear works with the smaller size cylinders. I still wonder if changing the nitrile 'O' rings on the William II/Brunel pistons for another type like viton would overcome this stiffness problem. Another question for Mamod at Peterborough - do they have any un-assembled cylinders available to try fitting different 'O' rings?

Chris Cairns.

Chris Cairns · Post by **Chris Cairns** » Sat Jun 22, 2013 10:43 pm

Seems that Mamod have other projects on the go at present.

The SP8 Beam engine has just been released as a solid fuel or gas burner, the "first made to order" gas fired SP7 stationery engine has been sold for £450, and a marine engine is being developed around 2 oscillating cylinders, a reverser/regulator valve and a gearbox for approx. £97.

Wonder how these developments are affecting the redesign of the Thomas Telford?

Chris Cairns.

Lner fan Sam · Post by **Lner fan Sam** » Sat Jun 22, 2013 11:04 pm

Hopefully these projects will give mamod some more experience in model making for the Thomas Telford.

Chris Cairns · Post by **Chris Cairns** » Sun Jun 23, 2013 1:43 am

Cannot see how Sam. The SP7 & SP8 use the piston valve cylinders which have been binned on the Thomas Telford (if you watch the videos of these engines in action you can clearly see the steam leaks from the piston valve rod & main piston glands but they both have flywheels which help keep them turning over), and the new marine engine mainly uses components off the Mark II locomotive.

They were supposed to be designing a new slide valve cylinder for the Thomas Telford which is new territory for Mamod.

Chris Cairns.

mikewakefielduk@btinterne · Post by **mikewakefielduk@btinterne** » Sun Jun 23, 2013 8:16 am

Perhaps there's a change in direction from the top. Maybe they're developing a twin cylinder, oscillating, steam motor that can be used to power both stationary and moving models.

If you look at the Regner catalogue ( http://translate.google.co.uk/translate ... %2Bwebsite and follow the link ), that's what they do, using an almost identical steam motors for their marine, loco and stationary offerings.

Of course the above is merely wishful thinking, as I haven't been directly in touch with Mamod recently. In fact, its not that long before the next Warley event at the NEC, which will be 12 months since I first saw the Telford and expected it to be on sale before last Christmas, which is somewhat troubling.

Mike.

Chris Cairns · Post by **Chris Cairns** » Sun Jun 23, 2013 1:53 pm

Mike, the prototype marine engine is discussed here - http://modelsteam.myfreeforum.org/A_Wor ... 63381.html Interestingly it is not provided with any form of mounting holes or brackets that I can see. And they are developing a matching internally fired horizontal boiler which again is new ground for Mamod.

However given that MSS have 2 versions of their marine engine available which none of the dealers appear to sell anymore ( http://www.steammodelsonline.co.uk/prod ... _MSE01.htm ), Wilesco have had 3 marine engines available for sometime, and there are others available from the likes of Regner I cannot see Mamod selling many of this marine engine other than to those who collect everything made by Mamod.

Chris Cairns.

mikewakefielduk@btinterne · Post by **mikewakefielduk@btinterne** » Sun Jun 23, 2013 5:25 pm

It would be nice if they then use the internally fired boiler on a loco. No more burnt paintwork.

They could even produce a tram engine.

Mike

DolwyddelanLightRail · Post by **DolwyddelanLightRail** » Sun Jun 23, 2013 7:49 pm

The only issue with producing a mamod with internal firing is that the boiler is small enough as it is, with a tube taking a lot of volume away, there isn't much water capacity in it. I have seen a mamod with an internally fired boiler and the owner had to keep a very close eye on the water level as it seemed to go through the water rather quickly!

mikewakefielduk@btinterne · Post by **mikewakefielduk@btinterne** » Sun Jun 23, 2013 8:15 pm

I think an internally gas fired loco would have to be Thomas Telford size rather than Mk11 size otherwise, as you say, it would only have enough water for a few minutes running.

Lner fan Sam · Post by **Lner fan Sam** » Sun Jun 23, 2013 8:47 pm

That motor there would make a nice steam motor.

I wonder...

Chris Cairns · Post by **Chris Cairns** » Sun Jun 23, 2013 9:56 pm

Yes an internally fired Mamod SL/MSS boiler would not last long. However you do not need a combustion chamber with an internally fired boiler so a larger diameter boiler could be fitted to the Mark II.

However I wonder what type of burner Mamod would used for the flue. The small round ceramic burners that Cheddar Models used in their flue boilers were very efficient and did not suffer from the problems that some of the current poker type burners fitted to internally fired locomotives suffer from.

The use of 2 oscillating cylinders and a reverser/regulator valve has been done before - it was how the PPS De Winton was developed and look how much the current RWM De Winton costs!

The problem with the RWM De Winton & Mamod Brunel's are the boilers and chimneys are a bit too tall for true 16mm scale so a tram built around their chassis's would be somewhat out of scale.

However we have drifted away from the theme of this Topic - the likelihood of a slide valve powered Thomas Telford.

Chris Cairns.

mikewakefielduk@btinterne · Post by **mikewakefielduk@btinterne** » Mon Jun 24, 2013 4:18 pm

The recent discussions prompted me to phone Mamod this morning for an update on Telford, plus what else they're doing.

I spoke to Peter who said:

The Telford is still work in progress, aiming to get a D valve finalised. No idea of dates.

The steam motor for a model ship or whatever will eventually be offered in two forms: oscillating cylinders that have already been mentioned, and also a little further down the line (no pun intended) with slide valves.

The modified Brunel style vertical boiler is looking good and not far away from release. A ceramic burner will be incorporated into the bottom of the boiler. It won't have the spiral re-heat tube as in the Brunel, but instead simple cross tubes.

The horizontal boiler with internal gas firing is not progressing as fast. From what I could understand, the boiler itself is complete but the type of gas burner is still being experimented with.

and that's all I know.

Mike

Chris Cairns · Post by **Chris Cairns** » Thu Jun 27, 2013 12:25 am

Looks like the current Mamod priority is to use up some of those piston valve cylinders that were originally made for the Thomas Telford. Already fitted to the SP7 & SP8 engines and now being used in a prototype marine engine as well.

A further update has been posted on the marine engines including the new vertical boiler here - http://modelsteam.myfreeforum.org/More_ ... 63630.html

Interesting that they are knocking around the idea of an LNER J70 style tram using the vertical boiler. Just hope they would stick with the oscillating cylinders for that one if it was to be built.

Chris Cairns.

mikewakefielduk@btinterne · Post by **mikewakefielduk@btinterne** » Sat Nov 23, 2013 2:46 pm

Just back from a fairly short visit to Warley at the NEC. While there spoke with David on the Mamod stand and he was able to show me the reborn Thomas Telford.

Basically they've given up with piston valves and fitted the loco with their standard oscillators. It should be on sale in January or so. Price still £430 (10% reduction off that if you pre-ordered with a small deposit at the show).

I took some pretty awful photos with my phone which I'll post in a wee while.

David said the TT will be replacing the Mk11 as their 'standard' loco. They're also planning a new saddle tank but I forgot to ask whether it would be based on the Mk11 or the TT dimensions. I suspect the latter as they're clearly aiming at getting into the Garden Rail market and away from being a steam toy.

They're going to fit a proper regulator and not the brass disk with a giant o ring as shown in the pictures.

And what about the work they're doing on a proper slide valve? That's more long term and won't see the light of day until they develop an internal gas-fired offering.

Also forgot to ask about the size and capacity of the in-line lubricator. Doh!

Pictures to follow.

Mike

mikewakefielduk@btinterne · Post by **mikewakefielduk@btinterne** » Sat Nov 23, 2013 3:02 pm

Pictures as promised. Pretty poor I'm sorry to say as I was holding loco in one hand, photographing with the other while constantly being jostled by the crowds around.

If these aren't visible to anybody else please let me know and I'll put them on Facebook.

Mike

Arcandier · Post by **Arcandier** » Sat Nov 23, 2013 3:09 pm

What's going on? I can't see the pics?

mikewakefielduk@btinterne · Post by **mikewakefielduk@btinterne** » Sat Nov 23, 2013 3:20 pm

That should work now. Hopefully somebody else at Warley will have taken better pictures.

Mike

Arcandier · Post by **Arcandier** » Sat Nov 23, 2013 3:23 pm

Works fine for me !

pauly · Post by **pauly** » Sat Nov 23, 2013 3:32 pm

the center couplings are certainly a positive development

mikewakefielduk@btinterne · Post by **mikewakefielduk@btinterne** » Sat Nov 23, 2013 4:13 pm

If this does replace the Mk11 they'll need to alter the rolling stock to centre couplings as well. In fact the height will be wrong too.

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Thomas Telford Locomotive - Take Two

The Thomas Telford is reborn.

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