What can one deduce from locomotive wheel arrangements?

[bi0boy]

Er...locomotives with small wheels didn't have gears, either. I've generally assumed that they went for large wheels because the engineering wasn't up to very rapidly reciprocating stuff, so you get more metres per revolution with large wheels than with small. Or, to put it another way, fewer reciprocations per km.

These things had tiny driving wheels (5'0"), but could do 90mph

But they were at the pinnacle of steam engine design, so I presume they'd got the design and engineering finessed to the point that you could afford to have everything thundering back and forth 200+ times per km without the engine shaking itself to bits, or smashing up the track.

Yeah that's what I meant i.e. for any particular engine if its driven wheels were made any smaller its top speed would have to be reduced.

 

[teuchter]

Other than the arrangement of wheels, of course.

Are there general rules of thumb as to the types and purposes of engines that might be best served by different configurations?

I see - for example - that 6-2-0 James was an experimental engine rebuild, of a broader type generally used as tender engines. Might one have been able to deduce the rendering aspect from the 0? Does the 6 imply anything, and / or relate to power? And why might one want more or less leading wheels?

You need to start by reading this

Leading wheel - Wikipedia

and this

Trailing wheel - Wikipedia

 

[kebabking]

So, has anyone contributing to this thread got a decent sex life?

 

[hash tag]

Define decent?

 

[OzT]

Any?

 

[editor]

So, has anyone contributing to this thread got a decent sex life?

Ah right. So if you have an interest in old technology then you must be some kind of weirdo that doesn't have a sex life? Very well done.

 

[hash tag]

One can appreciate steam engines AND have a sex life as I can vouch for BUT, what is classed as a decent sex life...it's all relative. X

 

[hash tag]

Well, that is until the wheels fall of.

 

[editor]

Look at this 0-6-0 beauty. Freight and passenger duties? No problem.

 

[SpookyFrank]

Ah right. So if you have an interest in old technology then you must be some kind of weirdo that doesn't have a sex life? Very well done.

I'm not super keen on the disparaging reference to autistic folk up thread either.

Frankly I'm glad there are lots of people who take an interest in how stuff works. If those people didn't exist then nothing would work, even in the unlikely event it ever got invented in the first place.

 

[OzT]

0-6-0 must surely be a shunter? Not good going round corners at any speed

 

[existentialist]

0-6-0 must surely be a shunter? Not good going round corners at any speed

Not necessarily to either. OK, so they're not going to be express passenger engines, but they were workhorses that got people to work, got goods to where they needed to be, and even did shunting

 

[bi0boy]

6 driven wheels would deliver some decent traction for a relatively small engine such as that.

 

[OzT]

...... but only in a straight line ..... lol!!

 

[existentialist]

...... but only in a straight line ..... lol!!

Rr, no. A short coupled wheelbase makes them particularly good at bends.

 

[bi0boy]

...... but only in a straight line ..... lol!!

Only capitalists need leading around corners:

 

[OzT]

Yes you're right existentialist, it has got a short wheelbase. Though maybe bi0boy the Soviet tracks are devoid of anything other than mild devations from the straight and narrow???


eta: Or is that a communist China train? Never sure if single red star's Soviet or Chinese

 

[bi0boy]

Yes you're right existentialist, it has got a short wheelbase. Though maybe bi0boy the Soviet tracks are devoid of anything other than mild devations from the straight and narrow???


eta: Or is that a communist China train? Never sure if single red star's Soviet or Chinese

True, Russia is pretty big and flat

For twisting mountain railways there is the geared 4-0-4

 

[OzT]

True, Russia is pretty big and flat

For twisting mountain railways there is the geared 4-0-4

View attachment 106365

Being pedantic here, or mistaken, but shouldn't that be a 0-4-4-0?

 

[existentialist]

Being pedantic here, or mistaken, but shouldn't that be a 0-4-4-0?

It's exactly the thought I had. "4-0-4" implies "no driving wheels", which would be a pretty fundamental design flaw in a locomotive.

 

[bi0boy]

It's exactly the thought I had. "4-0-4" implies "no driving wheels", which would be a pretty fundamental design flaw in a locomotive.

That's what I thought too so I googled it, but the first result was wrong

 

[teuchter]

It's more like a Bo-Bo or B'B' or something arrangement.

 

[editor]

0-6-0 must surely be a shunter? Not good going round corners at any speed

They generally worked branch lines, so 40mph was ample.

 

[existentialist]

It's more like a Bo-Bo or B'B' or something arrangement.

Under the UIC classification, yes. Not under the Whyte. They're essentially two ways of describing the same thing - it's only that by convention, we tend to use UIC for modern traction and Whyte for steam.

 

[hash tag]

Or, there is this for climbing hills


not clear from pic, but it has a sloping boiler/tank.

 

[existentialist]

Is that one of the Snowdon engines?

 

[hash tag]

Yes it is

 

[Mumbles274]

Ah right. So if you have an interest in old technology then you must be some kind of weirdo that doesn't have a sex life? Very well done.

#geeklivesmatter

 

[davesgcr]

Or, there is this for climbing hills

View attachment 106466
not clear from pic, but it has a sloping boiler/tank.

Original Snowdon railway engine back in service - BBC News

 

[hash tag]

This might help explain wheel arrangements and lots of other stuff

Flying Scotsman Manual