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Road Run Length vs Size

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Puffafish05/10/2018 10:57:27
15 forum posts

One thing I would love to do with my hypothetical miniature steam road traction wagon engine model machine would be to do a nice road run with it.

As it happens, where I live there is a miniature steam show about 10 miles away. So I was thinking about the practicalities of getting my miniature, getting steam up and roading it to the event.

There are various limiting factors in this:

  • Speed of the machine, which would be less than 16mph by law (as I understand it)
  • Practicalities of the roads, which I can gloss over for now, but while they are major-ish roads all the way, you’d probably feel ok on a bike, so would expect to be ok on a reasonable engine
  • Ability of the machine to keep going for the full ten miles (two hours?)

Advice which I’ve seen online seems to be that anything under a 3” isn’t worth putting on the road. It is just too small to be practical. If you have a 6”, then its fine, if not recommended to ride it on the road (Frederick the 6" showmans did a good long road run to GDSF this year I believe).

My issue is that the limited space I have means I’m looking at 3” or 4” machines. The largest I’ve been looking at is the 4” roller from STW, but I would prefer something smaller, like the 4” Simplicity roller, or maybe even the 3” Agri from Maxitrak or 3” Savage Samson. How practical is it to do a 10 mile road run with one of these?

SillyOldDuffer05/10/2018 12:35:01
4389 forum posts
956 photos

Someone else will have to answer about the average speed and range achievable with a small engine: I do know that the full size engine with trailer that once did the 30 mile round trip to Bath delivering coal from a local colliery took 2 days to do it, 3 if it was wet! I'm guessing the reason the journey took so long was that the engine moved at walking pace - less than 4mph, had to stop frequently to bunker fuel (from the trailer), take on large quantities of water, and to rest the crew. I doubt it moved at night.

On the road many things conspire to reduce average speed. One is the number of stops and restarts due to junctions and queues encountered on the journey. Running the engine down the cycle track on a dismantled railway will be much less trouble than traversing a series of busy main roads with an engine that doesn't accelerate well and has a low top-speed. (Driving to work in a car my expected commute time was nearly tripled in practice by traffic controls and other road users. Even worse in bad weather, or if there were road-works or an accident.)

Another issue is what you need to do when the engine breaks down halfway.

I think the logistics need careful planning, and suspect the engine would have to be followed by a support vehicle during a long run.

Another issue. At a show I love traction engines. On a busy main road, when I'm in a hurry to get from A to B, chaps pratting around and getting in my way with their caravans, horses, push-bikes, line-painting, drain cleaning, temporary lights, and theodolites get short shrift. Your innocent enjoyment of a fine traction engine out for a run on the open road might not be appreciated by the angry victims of the jam behind you. Even though I'm the most tolerant person I know, beware. Delay me 5 minutes and I'll tip your engine into a ditch and organise a lynch mob.




Edited By SillyOldDuffer on 05/10/2018 12:36:24

Michael James 505/10/2018 17:57:24
22 forum posts
There s facebook group for foden c type miniature engineering Ns a similar one for traction engines.I know some one did 80 miles in 1 day using 1 bag of coal on a 'rosebud' grate- a thick piece of mild steel with hundreds of 1
6 mil holes in it!
Paul Kemp05/10/2018 20:49:40
282 forum posts
9 photos

That is a question a bit like how long is a piece of string! There are a number of factors to consider here. Some are related to the engine, solid wheels (strakes or smooth rolls) or rubber tyres, boiler capacity and steaming characteristics, tender water capacity and how much 'spare' water can be carried on the outfit or availability of water along the route and coal capacity. Others are related to the terrain, how many hills and how steep on the route, quality of the road surface (very important in current times where a small pothole un-noticed in a car will be a giant obstacle to a small engine), general traffic speed and density.

There is no real reason why even a small (2" scale say) engine cannot travel a long distance in the hands of an experienced driver able to maintain a good head of steam. However you will find a 2" scale engine on strakes or solid rolls or even one fitted with rubber tyres quite frustrating on the road unless it is a dead smooth Tarmac surface. I have a 2" scale fowler Z7 ploughing engine which I have taken on a one mile road run (2 mile round trip). The first time I did it as built on strakes and it was fairly well shaken up! A good few things coming loose. I did it again having made removable rubber tyres which was much better but similar to a roller it has a very low road speed, the prototype was never designed for high speed running on the road.

I also have a 4" scale Ruston Procter with rubber tyres permanently fitted. I have done quite a few road runs with that but it's not easy to fire on the run so requires a stop every half mile or so for a stoke up and to clear the ashpan and top up the tender. It has a reasonable turn of speed in high gear, fast walking pace at least but it still suffers on poor road surfaces (although it's 4" scale it was a small engine in full size so more akin to a 3" Burrell in model terms). I have done runs of up to 4 miles with that and if you keep the pressure up it uses about a gallon of water a mile (if you let it drop below about 90 psi that can double!).

For a reasonably enjoyable and not too challenging trip in my experience you want something no smaller than a 4" Foster or Garrett. That means you are big enough to be a reasonable prescence on the road and more likely to be seen by 'normal' drivers. You have the capacity to drag a reasonable amount of water with you, a reasonable road speed and the wheels are big enough to not be overly troubled by the average road surface. As indicated by SOD there are a great deal of drivers with a similar mentality that have to be somewhere before they have left where they are! Consequently on major roads they will cut you up, squeeze past where really there is no space and generally act like you have no right to get in their way! On minor and country roads they will overtake on blind corners or approach you round a blind corner at breakneck speed with no chance of stopping! On a small steam engine you are more vulnerable than on a motorbike or even push bike so make sure your life insurance is up to date!!!! Sadly having also done some trips on a full size engine BMW, Mercedes and Audi drivers still consider themselves invincible and feel no threat from 15 tons of iron and steel in front of them!

3" scale rollers and Maxitrak Avellings are nice things for the rally field but you won't try a 10 mile road run a second time with one!

All the best,


Chris Evans 606/10/2018 09:19:37
1432 forum posts

At various times of the year I get full size engines passing my house. If I hear them in time I will go and watch them pass and maybe take a picture. Living on a main road we have a "pinch point" outside the house to slow the traffic, one day I nearly collided with a motorcycle on the pavement when exiting my drive The rider was to impatient to wait for a steam engine to pass through the narrowed road.

Things may be different for you by the time the engine is built we may have considerate drivers ?

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