Bad brakes.

[steam for ever]

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.

[Flying Pig]

Originally Posted by steam for ever

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

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?

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.

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.

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.

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.

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?

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.

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

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.

[Flying Pig]

Originally Posted by steam for ever

Back to topic, I believe westinghouse brake syestems are much better and they should not have mucked it up.

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 ?

Remember when the voyagers had trouble stopping?

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.

[steam for ever]

[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.

[garrat]

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

[ccmmick]

Originally Posted by garrat

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

Same here.

ccmmick.

[steam for ever]

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.

[garrat]

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

[steam for ever]

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

[ccmmick]

I spoke to soon.

ccmmick.