15 " radius

[arthur0109]

will any of the switcher locos run well on 15" radius? thanks

[Doneldon]

art-

Steam or diesel? Four- or six-driver steam switchers will generally handle 15" radius, especially those without tenders. For diesels, stick with short locos with four-wheel trucks only. If possible, try the loco out before you buy it. Fifteen inch curves are very, very tight. It won't be just locomotives which will have trouble. Freight and passenger cars over 40-45 feet won't make such sharp curves, either. It's not just length which causes problems. The ends of locos and rolling stock can bump into one another in tight quarters, usually resulting in a derailment. And don't even think of backing through 15" curves.

My point, if it's not obvious, is that 15" curves are inappropriate for all but special layouts like backwoods mining and logging railroads. Or some narrow gauge pikes. Be absolutely sure that you can commit to the difficulties of sharp curves before you embark upon constructing a layout within such parameters.
                                                                                                                                                                                                                                -- D

[jward]

to add to what doneldon said, i've never seen an industrial switching type layout which successfully used 15"r, though many of my friends have tried. if you absolutely MUST use 15"r, perhaps you should either model a trolley line, or switch to n scale where 15"r is quite a generous curve.

[on30gn15]

will any of the switcher locos run well on 15" radius? thanks

Given that the steam 0-6-0 with tender and the Plymouth WDT will both happily run around 9 inch radius, it's safe to assume they will do 15 just fine.
And do that with 40ft box cars and similar length hopper, gon, tank cars coupled.
Not gonna happen with 50ft cars.

Here, a Seaboard 0-6-0 rounding 9 inch radius curve on my On30 shelf layout.


Even thought it is not a switcher, the Fairbanks Morse will also do the 9 inch radius curve just fine, be back in a bit with video.
And the GP-38 which is of similar size will do it too.

[ACY]

Given that the steam 0-6-0 with tender and the Plymouth WDT will both happily run around 9 inch radius, it's safe to assume they will do 15 just fine.
Here, a Seaboard 0-6-0 rounding 9 inch radius curve on my On30 shelf layout.
Even thought it is not a switcher, the Fairbanks Morse will also do the 9 inch radius curve just fine, be back in a bit with video.

Here we go yet again, what radius you can get your locomotive to run on is not relevant to anyone but yourself because every locomotive is unique, no 2 are the same. Some will run on tighter radius then others and there will often be no rhyme or reason behind it.

[on30gn15]

Here we go yet again,

Where we goin?

Or is is because I embarrassed your assumption of authoritarian elucidation by daring to empirically demonstrate answers to

will any of the switcher locos run well on 15" radius? thanks

[on30gn15]

And don't even think of backing through 15" curves.

Yeah, just like he said,

[on30gn15]

because every locomotive is unique, no 2 are the same.

What, you mean there are no standards in mass-production?

[Doneldon]

On30-

Don't pick on ACY. He's right.

Some locos of a given type and manufacturer will handle a particular curvature and, for unknown reasons, others will not. We've all seen this. And it doesn't mean there are no manufacturing standards. Say the standard for locomotive X is that it traverses 18" radius. Every model may do so but that does not mean that there won't or can't be a few which will handle something tighter.
                                                                                                    -- D

[Jim Banner]

Based on my own experience, I have to agree with Doneldon about sticking to 4 axle diesels, six coupled switchers and 40' or shorter cars.  Where I disagree with him is that I have no problems backing short trains around such curves.  I do so regularly on a branch line with 6% grades, 15" radius curves, switch backs and a small switching yard.  I suspect the people having problems with compact switch yards using 15" curves are either trying to switch bigger equipment or made the mistake of using S-curves in their track work.

Before building this branch line, I did extensive testing and found that on flat track, most of the above equipment would run on 10" curves and all of it would run reliably on 12" curves.  However, when I put the 12" curve on a grade, the twist imparted by the helical curvature rendered the track unreliable.  I had enough room for 15" curves, used them, and have had no problems since.

While I agree that not all locomotives of a particular brand and type are identical, I have to agree with 0n30 that if one exemplar will run on a 9" curve, it is very, very likely that its sister locomotives will run on 15" curves.  Would any of us claim that identical locomotives are so different from one another that even though one will run on 18" curves, there will be others that need more than 30" curves?  Those 30" curves are a whopping 67% larger in radius than 18" ones, just as 15" curves are the same 67% larger in radius than 9" ones.

Bottom line, arthur0109 should have no big problems using 15" curves as long as he sticks to rolling stock as listed by Doneldon, runs short trains, and uses at least a half section (4-1/2") of straight track between curves in opposite directions in order to avoid S-curves.

Jim

[jonathan]

Likewise, I have no problems running 6-coupled steamers and 4-axled diesels through 15" radius track.  And scale 40' rolling stock has no problem moving through the curve.

I also agree some testing is in order, as I have some larger equipment that will pass through a tight curves.  Most of my 2-8-0 Connies will do it (not the sound version).  I have a few six-axles diesels that will make the turn, but cannot pull any cars due to the wide overhang.

Smallish trains go on the 15" radius loop.  Larger trains go on the 22" and 24" radius loops.  That how my trains go...

Regards,

Jonathan