Bad brakes.
 

It is noted that Diesels have bad braking systems compared to steam.

Steam locos ceased major production in 1960, and so 50 years of technology has passed, yet still the standard of stopping power has not become better than steam locomotives.
I find this terrible.

The reason for the problem is that now disc brakes are used which can overheat and lose effectivness, whereas steam locos had brake pads which worked by directly pressuring the tyres.

Now something must be done and if we must have diesels and Electrics, at least improve the standards as the lack of effort here is appalling.
Anyone with me on this?

What is important, is there a solution?
Can we not have direct pressure brakes on modern traction?

Where did this information come from ?


Were disc brakes not an improvement then ?

Having spent many years selling brake components to the transport industry brakes are of particular interest to me and I would like to find out a lot more on loco braking systems.

I have never driven diesels, but I know someone who has done.
They said it was terrible.
Why do you think diesel brake tenders were invented?
The braking power was much weaker.

To the best of my knowledge diesel brake tenders were only used on unfitted trains, where the loco brakes were not enough to stop the train unaided.

But, even in steam days, unfitted trains had to have some wagon brakes partially applied when going down steep gradients because the loco brakes could not cope.

Perhaps some of the ex steam and diesel drivers on here would like to supply a little "evidence" ?

To be perfectly honest, until today I did not know that diesel brake tenders even existed, we live and learn !

http://www.semgonline.com/diesel/dbt.html

Hi SFE, Congratulations on your promotion.
If I remember correctly, brake tenders were introduced with the EE Type 3 (later class 37) because their introduction meant heavier trains could be run at higher speeds. Remember that most freight was carried in unbraked stock, only the locomotive and the guards brake van had brakes. The extra speed and weight required more braking power.
I clearly remember the brake tenders being used on the North Eastern main line North of York in the early 60's.

Thanks Tony.
I notice a difference on DMUs as well , and I mean modern class 150's!
On an ordinary day the train will round the corner about 100 yards away at about 10MPH and still the two oach train will shoot past us all and we have to chase it down the platform in order to get on.
I suppose it is the type of engines as well and also regulations.
You can't just slam it into reverse anymore to stop it.
Thats right health and safety have arrived.

I read recentl that the class 40 locos were withdrawn earlier than expected as their brake power was actally less effecient than a class 37. This meant that the 40's, although more powerful than the 37's, and being able to haul longer/heavier freights, were unable to efficiently stop a freight, taking ito consideration their own weight; it was therefore more suitable for 37's to haull shorter trains knowing that they could brake when required, being somewhat lighter than the 40's.

Now you see this is whi I have got such strong views that steam was withrdrawn too early.
if they really had to, just work out the problems first, however small they are.

We used to use brake tenders on ballast trains for more brake force.
The CDA clay wagons that were brought into use in 80s only had 2 disc brakes on opposite wheels the other two were handbrake only and you had to be on the ball going down Luxulyan Valley a 1in37 and a thousand ton train.

ccmmick

SFE - your main contention about brakes ceased to be an issue when fully fitted goods trains became the norm, and that was very many years ago !

The way you make things sound is not representative of how things really are and steam locos were no better in their heyday.

I know I'm just biased!:D
Still when going light engine is concerned it is better to be safe than sorry.
I have also heard that steam did better when there was leaves on the line.
Was this to do with brakes?

You can not compare steam brakes to modern day all trains as you all know are fully fitted not so years ago.
Brakes on a hst has awesome brakes i was never passed on them but i have driven them many times and going back to the silver bullets the air brakes on the are fantastic.
I know what you are saying SFE and yes all loco brakes on there own are not that great but modern day brakes are a lot better they have to be.

ccmmick.

Nothing at all to do with the brakes a train will slide steam brake or air brake.

ccmmick.

:DYour probably wondering how I got to be CME now.
So am I!:D

Seriously I don't design diesels as I leave that to the engineering team and I design the steam and rolling stock, so that explains the ignorance.

The reason I write this thread is that we are having some trouble with diesel style test bogies and brakes and so far they are not working very well.
We have seen that when the brakes are left on, the discs will run hot and they are useless.

Is this the same on all diesel locos?

If you ran your car with the brakes on, the discs would soon get VERY hot and you would get "brake fade" ! (ie no brakes)

Most vehicle front brake discs are now ventilated to make them dissipate heat quicker.

Thanks Pre65, we will go and alter the brakes now.
There is probably some of those spare in the workshop.

Hi SFE ! Don't mean to be rude (especially in the festive season :D) but I think your "title" is a bit of an affront to the preservation movement.

At the very least I would expect a CME to have some mechanical qualifications and a real understanding of railway matters.

Hi SFE
Why not use brake blocks on the wheel tyres on your diesels, mine has 4 blocks in a similar style to steam loco's except they are air powered. if anything they can be too good if not handled with due care.
Regards

Sorry Pre65, as it is the festive season, I am also drunk.
Not incredibly, but enough to be as much use as a chocolate teapot.

6678bjm, that is quite a good idea, in fact we tried that before but none of the parts fitted.
The design created by the team involved discs and to do this we will need to alter the bogies, which will take a week ot two to design and rebuild.

I am now drinking lots of water as i see I am placed on the spot a bit.
Heres my experience just for you Pre65.

I started building minaiture locos for people to designs done by my grandfather about 10 years back, who was pretty much head of everything.
I steadily built larger and larger locos up to 15 inch guage for a private site.
3 years ago my grandfather died, but after being second to him i took the drivers seat as it were and now I have built 3 locos to my own designs and yes they work.
This is why I am CME now.

Anyway we are only just getting up and running on the scale we want so this is why I enquire.
Hope that clears it up.

Back to topic, I believe westinghouse brake syestems are much better and they should not have mucked it up.
Remember when the voyagers had trouble stopping?

Anyway I am absolutely knackered now, I'm off for an early night.

This is a muddled and very misinformed thread!

Do you really think that they would allow a poorer braking system in this Health & Safety crazy world that we live in?

And you source for this is what? Where is your data? I'm afraid that this is utter tosh. If there were a single incident where the brakes on a train were substandard due to poor design the subsequent enquiry would say so. The signalling system in this country requires trains to be able to slow down in accordance with the length of signal sections. If brakes were as bad as you say trains would be running by signals all the time due to poor brakes - and they're NOT! The media would have a field day, so it would be well publicised and we'd never hear the end of it.

Which would be why they use cooling rotors on the axles. Disc brakes can suffer from fading if they are used heavily, but they are an excellent system - that's why you find them on cars and lorries too.

Ah, now you mention Electric trains. Most new designs in the last 20 years have included Rheostatic brakes, which can best be described as vicious ! They are extremely efficient and effective. To compare these to a vacuum brake is crass.

Disc brakes are excellent. The only acknowledged advantage that tyre braking has over disc systems is that in leaf fall and railhead contamination situations the brake shoe cleans the tyre surface.


I have to say that I find this a very strange attitude for an ENGINEER to have. There isn't a single fact in the whole thread. No comparison of stopping distances, brake forces, or even mention of locomotive types. VERY untechnical.

Hmm, every train I've ever driven had Westinghouse brakes - and they all stopped where I wanted them to. What exactly did they muck up ?

Indeed I do. And I know the reason as well. Here are the FACTS...

Under low adhesion conditions drivers are told to use less brake (and apply it earlier), in order to prevent wheelslide - this is true for all trains, even steam ones.

When the Voyagers were first introduced the Train Operating Company (I'm deliberately not naming them) didn't appreciate that the Voyagers brakes are so efficient, that on the first few notches of brake controller it only uses a few of the available axles to brake with. When you move the controller further it brings more brakes into operation.

As you can imagine, when the train is sliding on a slippery rail you want as many axles to be braking as possible. So what the driver should have done is use a higher brake step so that all the brakes were working, and left it to the WSP (Wheel Slide Protection - which is similar to ABS in cars) to deal with the slide.

The effect of this was that the train didn't behave in the way that the driver had predicted, and it hit the stops. This was all at low speed.

So the reason was failure of the operating company to appreciate how the technology differed from previous trains, followed by its failure to implement an appropriate new Company Driving Policy. The enquiry found that the brakes were working properly and not to be at fault.

This information is not priviledged, it was in all the papers and therefore available to anyone with enough railway/technical curiousity to look for it.

[QUOTE=Flying Pig;36567]
Which would be why they use cooling rotors on the axles. Disc brakes can suffer from fading if they are used heavily, but they are an excellent system - that's why you find them on cars and lorries too.

QUOTE]

Hello flying pig.
I am pretty much sober now and i see the big mess I have made.

In your statememnt shown above you say that disc brakes are an excellent system. Just before that you say that they can suffer from fading.

This to me just does not make sense.
On trains they will be used heavily and even if ventilation helps they will be shockingly expensive.

Last night when fixing that bogie I was on about we went to order the brakes and they were £10,000 just for the discs.
I only had to pay 500 buying pads.

Pads and discs are essentially the same, a pad is forced onto a disc (disc brakes) and pads are forced onto wheels which act in a similar way.

Wheel pads just cool better, the only downside here being in wet weather grip may not be as good.

(sigh) I can tell this is going to be a veryexpensive day for me.

Thanks for all your help.

Steam Forever Have you got any photos of the engines you have built would love to see them

Same here.

ccmmick.

yes indeed I have.
I seem to be having a bit of trouble loading pics onto the computuer aat the moment (it says my camera cannot be found) but i think I have some drawings that I could scan.

oh thats a shame .if you have problems with loading just ask i am sure there are folks on here who can help

Thanks garrat.
it seems to be working now, should'nt be long.

I spoke to soon.

ccmmick.

I will be back soon. I'm just off down to Lindow workshops to get some drawings for you.

Oh would rather see the photos I will wait with baited breath for the photos not the drawings

Don't hold your breath Garrat are we not still waiting for the pictures and videos from the B&MLR thread.?

SFE when did you change career? back in August you were training as an architect,and looking for companies who built locomotives,now it seems you build your own, excellent news I could be in the market for six new tyres for a loco.

This is'nt my observations but a friend of mine has noticed you seem to post alot more when the schools are on holiday care to expand on this?

Cheers John

Thanks John I can now breath out. friends of mine have built locos and the first thing is to show me photos of their achievements .Come on SFE get them on the gallery for us all to admire your wonderful work.We could be buying and putting monies in your pocket

Hi guys i have just got back.
I will start downloading onto my computer soon.
Do you think I had better start a new thread on this?
We have gone a little bit off topic.

Its christmas what do you expect?
I don't work much weekends and i have 6 nephews and nieces to spend time with.
i choose my own holidays as well.
i try to be a family person.

I think this thread is sailing pretty close to the wind. Any objections to its closure?

Go on close it.
I for one think it has run dry.
Its gone far off topic.

Done and done.