A speedometer for the layout?

[StephenBCT]

Black Cat Technology produce a wagon cable of measuring he relative speed in either miles or kilometres per hour. Only problem is they are in rather short supply, see web site http://www.blackcattech.co.uk

 

Sorry for picking up on an old post - just getting back in to things. If anyone is interested I now have plenty of stock of these - it's the old story, when I was struggling for time to build them I could sell as many as I could make. Now I've managed to build a large batch no-one wants them!

[DCB]

Just off to Calne tomorrow and looking for my own speed measuring post and failing miserably, but all these speed calculations are backwards for a model train.  

 

How do you measure the length of a piece of track and more important how do you see both ends to use a stop watch? (Or see a wagon speedometer?)

 

You can't.   However you can measure the length of a train to within about 5%and then time it passing a fixed point.     7 X 60 ft coaches is around 420 feet   7 X 64 ft coaches around 448 feet  6 X 75 ft coaches is around 450 feet   1/12th of a mile is 440 feet   1/12th mile + or - 5% is 420 to 460 feet.

 

As 1/12th of a mile is covered in 1/12th of a minute at 60 mph and 1/12th of a minute is 5 sec you can simply time the train past a set point.

 

You just need to measure the time.  Either by stop watch or second hand, counting Nought, One Two etc (Don't start the count with "One" and count one second too few)  2.5 sec = 125mph   3 sec =100mph   4sec = 75 mph  5 sec = 60 mph   6 sec =50 mph   7.5 sec = 40 mph  10 sec = 30 mph, 15 sec = 20 mph  30 sec = 10 mph.

 

This works with all scales from 300 mm/ ft to 1 mm/ ft

 

Halving the length of train and halving the time gives the same result.   Wagons are more difficult, most are over length in 00 and N but roughly 3.5 wagons = 1 coach so 24 wagons per 1/12th mile  so you can extrapolate, 12 wagons need  5 sec to pass at 30 mph.

[davetheroad]

I just have 2 markers in my through fiddle yard. A train that takes 8 seconds to travel between them is going 60mph. A marker half way gives 30mph in 8 seconds. No need to be exact, I use a little bit slower for 25mph and a little bit faster for over 60mph. Eventually you learn to judge the approx speed by eye.

[loickebros]

You could just get one of these

http://store.sbs4dcc.com/ModelRailroadTechnologiesAccutrackIITrainSpeedometer.aspx

[coachmann]

On a slightly different tack, fit sound to a model steam locomotive and your ear will tell you whether a loco is accelerating too fast or is going too fast. If I turn the sound off I find my locos dashing around all over the shop.

[bgman]

To get a clearer picture and the best results it's best to know which country you're modelling

 

Either American

 

 

Or British

 

 

Once you know this its just a matter of pacing yourself for the best resultant speed !

[Metr0Land]

Don't forget India!

 

[OnTheBranchline]

Roughly, in 4mm, a foot per second is 52mph.

 

60mph is about 14 inches per second

 

30 mph -7 inches per second

 

It 's slower than most people think

 

Edited January 22, 2018 by OnTheBranchline

[10000]

Didn't see this mentioned on here. I would imaging that it can be configured for '00' as it can be used on 'H0' and 'N'

 

https://www.tcsdcc.com/Customer_Content/Products/Train_Speedometers/index.php

[DCB]

 

The speed is a lot less than  675 kmph 400 mph  Its passing 3X Mk2s in a second and lapping what looks like an 8X4 in 5 seconds that's about 15 feet round.  Both add up to 3 feet / sec 150 mph based on the figures provided and around 130 by the figures I use.

[The Johnster]

I find that making imaginary chuff chuff noises at the rate of 4 per revolution of a driving wheel gives you a fairly good indication of speed, but I am old enough to remember what a steam loco sounded like accelerating from a platform and aware that some (not all!) heritage railways give a 'false' impression, either because they are understandably gentle with their prized locos and trying too hard save on the coal bill to replicate realistically the careless rough and tumble of BR working, or creating the opposite effect using industrial locos with small driving wheels which sound like they are doing the ton at 25mph.

 

This suggestion is of course of no use to those who do not remember BR steam, and to those who model diesel or electric prototypes.  My advice is to spend time around real railways and listen to the wheel beats over joints and pointwork, and translate this to your layout working as a rough guide to speed.  I have replicated this on my layout by cutting grooves into the rail heads at suitable spacing to generate wheel noise on jointed rail, but this is of no use on layouts which replicate modern CWR, so you will be reliant on turnouts and junctions.

 

My impression from going to shows and looking at videos is that running speeds are generally 'modelled' quite accurately by most folk (bit fast on short wheelbase steam era freights sometimes), but that rates of acceleration and braking are far too rapid; it's a train, not a car.  Speed through curves is often excessive as well, but a compromise must be struck between practical curvature and running here.  A number 4 curve scaled up would have a 15mph speed restriction, no 1 would need to be negotiated at walking pace by tiny 0-4-0s only, and if you want to run at HST or higher speeds you will be looking at 20 feet radius if you don't accept some compromise!

 

A ride in a train anywhere on NR will show how long it takes to achieve running speed from a start, and to stop smoothly from running speed, and give an indication of the distances involved and how these are affected by loads and gradients; the distances are miles rather than yards.  Steam locos on anything except express passenger work, and especially on local passenger traffic, could easily match the modern diesel performances and many timings have not been altered for over a century (though loadings and dwell times have).  Electrics can accelerate much harder, but are still limited in the rate of slowing down in order to preserve passenger comfort at a reasonable level (especially on services where half the passengers are standing) and avoid skidding on wet rails.  Large wheeled steam engines on heavy expresses accelerated slowly to avoid slipping, particularly pacifics, and performance was often 'plodding' up the banks out of London termini, and modern traction has made a massive difference here!

 

My imaginary BLT is some 12 feet long on the scenic side of the fiddle yard break, and I have imposed an arbitrary 40mph speed limit on the branch.  I try to start as smoothly as possible and accelerate steadily. this is achieved by allowing the train to settle to the new throttle setting for a second or so before moving the knob a little more clockwise.  My passenger trains are usually doing about 30mph by the time the last vehicle disappears into the fiddle yard.  Arrivals come in at about the same speed, having just having had to blast up an imaginary short but steep incline, and are 'braked' fairly sharply as they approach the platform and then more gently to a 'precision' stop with the coaches beneath the canopy so the passengers can alight in the dry.  Freights are held at the home signal and enter very slowly as they drag their loads off the bank, and are only allowed a slight acceleration as they clear it, as it is now only a hundred yards or so before they must bring their unfitted trains to a stand at a stop board!  

 

Similarly, outgoing freight is not allowed to develop much more speed than the 15 mph restriction through the loop turnouts as they must descend the imaginary declivity with some caution; loaded coal trains with Oxford wagons have their handbrakes 'pinned' down!

 

Mr Churchward's policy of standardisation helps me; 6 out of my 7 engines have 4'7" driving wheels.  All have slightly different personalities and characteristics, though, despite 4 of them having fundamentally the same Bachmann mechanism, and require slightly different driving techniques; you just have to learn them!  Some almost drive themselves, others require a more 'hands on' technique.

 

You will be able to apply similar thinking and driving technique to your own layouts.  It is worth the effort; your operating sessions will be more satisfying and realistic!

 

 

My partner is used to the fact that I'm a bit nuts, and has so far not commented on the chuff chuff noises, though she rolls her eyes a bit!  Then she wants to drive, and makes 'de dum, de dum' noises...

Edited January 23, 2018 by The Johnster

[Junctionmad]

If one accepts most layouts are compromised in length compared to the prototype , one generally has to accept that acceleration will be greater then the prototype , otherwise most trains would have run into the fiddle yard buffers before ever getting up to speed and look unrealistically slow

[JZ]

I run my locos to run over a scale 1/10th mile/524 ft or 131 inches in 4mm scale. Time them over that and you get your mph. I am DCC and can then set the top speed according to loco type and use. 6 seconds is 60mph, 18 is 20.