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Minimum Radius, What are the Consequences?

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  • Member since
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  • From: Bradford, Ontario
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Posted by hon30critter on Wednesday, February 25, 2015 4:39 PM

I'd be more concerned about damage to the layout, as in when you tear up the tracks to rebuild it.Smile, Wink & GrinLaugh

My concern is that you will spend money on the big steam locomotives and they will end up as shelf queens because you can't run them successfully.

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by DigitalGriffin on Wednesday, February 25, 2015 3:41 PM

What will happen?

Hundreds of voices will cry out in 1/87th volume as your train derails and plummets onto the ground.Clown

Don - Specializing in layout DC->DCC conversions

Modeling C&O transition era and steel industries There's Nothing Like Big Steam!

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  • From: Jersey City
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Posted by steemtrayn on Wednesday, February 25, 2015 3:06 PM

A large engine might take the curve, but will look silly doing so. And silly looking trains is not what this hobby is about.

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Posted by wjstix on Wednesday, February 25, 2015 3:05 PM

Over a long time, I suppose it's possible it could affect the driving wheels negatively. I have a BLI 2-10-4 with 24" recommended min radius. In tests I could get it go around a 22" radius curve, but the wheels squeal pretty bad. I imagine over time that could cause wear and tear on the wheels.

If your layout space only allows for 18"R HO curves, you'd be best to stick with smaller engines - 0-6-0 switcher, geared steam, etc. 

Stix
  • Member since
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Posted by dstarr on Wednesday, February 25, 2015 3:02 PM

S. Connor

I have 18''R turns on my layout. I am looking to expand my steam collection (HO Scale) with some larger locomotives, but am worried about the consequences of running more drivers on such tight curves. Most locomotives I am looking at have a recomended minimum radius of 22''.

Can any damge be done to the locomotive by running on tight curves?

 

Not to worry about damage to locomotive.  The issue is derailment.  If the maker puts "22 inch radius" right on the packaging, you can be pretty sure the locomotive will derail on 18 inch curves.  Maker's go to a lot of trouble to get their product to handle 18 inches, since that is the standard radius in train sets.  When engineering fails to squeeze the locomotive around and 18 inch curve,  marketing reluctantly allows the "22 inch radius" mark on the packaging to reduce the amount of product returned by customers  for derailment. 

   If the package says "22 inch radius" it is best to believe it. 

  • Member since
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  • From: Culpeper, Va
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Posted by IRONROOSTER on Wednesday, February 25, 2015 2:50 PM

Running a locomotive on a too tight curve could result in a derailment.  Or depending on the speed it could turn over (if near the edge it could end up on the floor) which might damage some of the detail.

Since 18" is popular in HO, manufacturer's generally try to make their locomotives run on it.  When they can't and advertise it at 22", you probably will have problems at 18".  Running it very slow might keep it on the track.

Enjoy

Paul

If you're having fun, you're doing it the right way.
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Posted by dknelson on Wednesday, February 25, 2015 2:49 PM

One more point - sometimes an engine can run on a low radius, but when you couple cars behind that engine, the overhang derails the coupled cars -- or derails certain cars.  The minimum radius that is mentioned in product reviews or advertisements does not always take that into account.

Dave Nelson

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  • From: Sebring FL
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Posted by floridaflyer on Wednesday, February 25, 2015 2:43 PM

Won't damage the loco, but in all likelyhood loco will derail. You might get lucky with a specific loco but generally larger locos will not run reliably on smaller radius.

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Posted by 7j43k on Wednesday, February 25, 2015 2:37 PM

If you can get a locomotive recommended for 22" curves to operate on 18", I don't believe the locomotive will be damaged as a consequence.

 

The manufacturer is suggesting that it WON'T operate on 18".  As in it will not fit.

 

 

Ed

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    April 2003
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Minimum Radius, What are the Consequences?
Posted by Anonymous on Wednesday, February 25, 2015 2:26 PM

I have 18''R turns on my layout. I am looking to expand my steam collection (HO Scale) with some larger locomotives, but am worried about the consequences of running more drivers on such tight curves. Most locomotives I am looking at have a recomended minimum radius of 22''.

Can any damge be done to the locomotive by running on tight curves?

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