absolute minimum radius for Bachmann 4-6-0 and 2-8-0

[NevinW]

I have a number of Bachmann Spectrum 4-6-0 and 2-8-0 engines, some that have been modified with the Vanderbilt tenders.  I am trying to fit a wye into one yard for turning engines and the only way if fits is if I drop the minimum radius on the wye to about 16 inches.  Only the engines would use this wye so couplers aren't an issue.  Will these engines behave on that tight a radius?  Thoughts and opinions?

[jonathan]

I have run my 2-8-0s on 15" radius curves, pulling short rolling stock to boot.  This is below the recommended radius.  Some Connies will do it, some won't.  I would test your locos on small curves, just as a test.

Our say-so may not be sufficient in this case. 

Regards.

Jonathan

[electrical whiz kid]

One thing to watch is on small engines:  The drivers are usually all flanged.  Larger rigid-frame locomotives will invariably have blind drivers-unless you have really broad radii so that binding etc would not b e a problem.  Flanged drivers, if going through too tight a radius, will tend towards binding, and will probably jump the rail, but might just sit there and hum...(Consider that to be the mechanical equivalent to groaning...).  To my mind, I would take the minimal recommended radius, and slack off of that a bit.  If you want that wye, you will have to make other adjustments to scenery, etc.  You will NOT want to ignore a potential problem like that.

Rich C.

[rogertra]

One thing to watch is on small engines:  The drivers are usually all flanged.  Larger rigid-frame locomotives will invariably have blind drivers-unless you have really broad radii so that binding etc would not b e a problem.  Flanged drivers, if going through too tight a radius, will tend towards binding, and will probably jump the rail, but might just sit there and hum...(Consider that to be the mechanical equivalent to groaning...).  To my mind, I would take the minimal recommended radius, and slack off of that a bit.  If you want that wye, you will have to make other adjustments to scenery, etc.  You will NOT want to ignore a potential problem like that.

Rich C.

Rich.

Define "really broad curves."

I use a 30" minimum and then only in hidden staging and don't consider that a "really broad curve" rather a typical acceptable minimum.  Out in the open I use 36" or greater.

The 2-6-0 and 2-8-0 will operate fine on 18" curves, if you really have to use a curve that tight.  Most RTR locos, steam and diesel, will operate on 18" radius curves, it's kind of a defacto industry standard that engine will operate on curves that tight.  Even most 2-10-2s will go round 18" curves but look silly doing so as they gap between tender and cab will be way to wide.  :-)  After all Bachmann as well as other manufacturers design their models for "train set" curves otherwise they wouldn't sell.

The exceptions will, in general, be articulated locos but read the packaging or Google for product reviews.  It's all there on Google, all you have to do is take the time to find it.