How many is too many?

[OuBallieParticipant @ouballie]

Coupled wheels that is.

[OuBallieParticipant @ouballie]

With Workshop time on hold for now, I've been able to catch up on reading my collection of The Model Engineer and Electrician.

My brain took a while to catch up with what my eyes where seing.

First thought was "Not possible", but then the old saying 'Photos don't lie' came to the fore.

Cut and paste in the 1920s being just that, scissors and glue, and easily discerned, unlike today where that old saying is well passed its usefulness.

I thought, (dangerous I know) that 10 coupled was it.

How many of those wheels would be flangeless and what would be the minimum track radius I wonder.

Geoff – Been waiting to cind out when 'LBSC' appeared, and he did so in "Battle of the Boilers" during 1922.

Edited By OuBallie on 13/01/2015 10:22:04

[Neil WyattModerator @neilwyatt]

Looks like the centre two are flangeless, and flanged axles have extra play.

Obviously not what the north Americans call a 'switcher'!

Neil

[OuBallieParticipant @ouballie]

Oops!

Didn't read the details, where all is explained.

Geoff – Sodding infection. The only excuse I can hide behind.

Edited By OuBallie on 13/01/2015 10:42:11

[OuBallieParticipant @ouballie]

The first was feeling a little lonely, so added this for company, it having a 4-wheel leading and 2-wheel trailing bogie plus a 6-wheel tender.

Replace the trailing bogie with a 4-wheel one and that would be it for a coupled loco me thinks.

Geoff – Stick welding has improved

[Howard LewisParticipant @howardlewis46836]

The Union Pacific 12 coupled loco. used conjugated valve gear with what looked like the Gresley/Holcroft design. The locos were numbered in the 9000 series.

I think that Russia made a 14 coupled loco, but could only be useful on straight track.

Lots of tractive effort, but locos with so many coupled wheels must have been barred from any track with a distinct curvature!

The British rail 10 coupled 9F s had flangeless centre driving wheels, and probably a lot of side float on the other axles. Not only could they pull, but could run at express passenger speeds when required! Possibly the last and best steam locos made in Britain.

The alternative was use an articulated loco like a Garrett or a Mallet, (although, strictly, Mallet were compounds). Some U S railroads, such as Union Pacific ( Big Boys and Challengers) used simple expansion articulated locos.

Garrets were simple expansion machines, with a large boiler articulated above the engine units, and came in 4, 6 or 8 coupled forms..

The Erie Railroad even had a Triplex, (The Matt H Shay) described as a Mallet, with an engine unit under the tender, as well,

On a smaller scale, the logging roads used two (or even three) truck Shays, others used Heisler or Climax locos to obtain sufficient traction on sharply curved track. poorly laid in the woods as a temporary measure. But these were mounted on two axled trucks, to use full weight for adhesion, and flexibility.

The Shay power unit was usually a three cylinder mounted on the right hand side of the loco, driving the trucks through longitudinal shafts and bevel gears. The Heisler had a V twin steam engine mounted under the boiler, driving each truck, again via longitudinal shafts and bevel gears. The Climax prototype was merely a steam engine and boiler mounted on a flat truck and driving via chains.

Howard

Edited By Howard Lewis on 20/05/2015 18:40:40

[SaxalbyParticipant @saxalby]

Yes the 14 coupled Russian Andreev loco.

Maybe do one in 7 1/4 gauge.

Anyone know of a club with a long straight track?

[Another JohnSParticipant @anotherjohns]

If you are going to "do it", then, do it right!

I've seen one of these locomotives in person (Steamtown in VT) and, impressive is the word. I think that Mallard would fit in the firebox…

Photo of our hero Keith with a locomotive he did some work on running on the Montreal track:

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