N Gauge Forum

General Category => N Gauge Discussion => Topic started by: Spanners70 on July 11, 2026, 05:36:03 PM

Title: Temperature limit
Post by: Spanners70 on July 11, 2026, 05:36:03 PM
Anyone know what the critical temperature may be before damage occurs to rolling stock and locos? My loft is currently 49'c most I can take is 5 minutes before I have to come down... got me wondering
Title: Re: Temperature limit
Post by: PLD on July 11, 2026, 06:24:18 PM
Quote from: Spanners70 on Today at 05:36:03 PMAnyone know what the critical temperature may be before damage occurs to rolling stock and locos? My loft is currently 49'c most I can take is 5 minutes before I have to come down... got me wondering
I vaguely recall a lower limit being advised, but I don't think any manufacturer has ever stated an upper limit...

What some do panic over in hot weather is the expansion of track, but even those concerns are over-blown - the Coefficient of Expansion for Nickel Silver is 16 × 10-16 /1 degree C, so you need around a 64°C temperature change, for a 1 metre length of flexitrack to expand by 1mm!

Title: Re: Temperature limit
Post by: ntpntpntp on July 11, 2026, 06:29:03 PM
Well I'd certainly bring locos and stock down and out of that heat, I'd be concerned about plastic warping or cracking due to expansion of the metal chassis within.

I've always maintained that "raw" lofts, garages, shed etc. are no place for a model railway.
Title: Re: Temperature limit
Post by: Yet_Another on July 11, 2026, 06:44:46 PM
How hot does stuff get in a container on a ship passing through the tropics?
I suspect that's more of a test than a loft.
Title: Re: Temperature limit
Post by: ntpntpntp on July 11, 2026, 07:04:21 PM
Quote from: PLD on Today at 06:24:18 PMWhat some do panic over in hot weather is the expansion of track, but even those concerns are over-blown - the Coefficient of Expansion for Nickel Silver is 16 × 10-16 /1 degree C, so you need around a 64°C temperature change, for a 1 metre length of flexitrack to expand by 1mm!

That may be the theory based on the material properties, but believe me I've had fiddleyard track start to snake in my conservatory at 30 degrees (only in there for testing before a show), and in hot exhibition halls.  It's only loosely pinned compared to the fully glued and ballasted track on the scenic parts of the layout - that's never suffered.
Title: Re: Temperature limit
Post by: scottmitchell74 on July 11, 2026, 07:08:24 PM
My stuff including my 25+ year old current layout have always been in my W. Texas garage with yearly swings from about 0 to 43 degrees.

Things are sluggish in the Winter and need more warming up, but things still work.

For what that's worth.

49 might be a different animal! :goggleeyes:
Title: Re: Temperature limit
Post by: KevTheBusDriver on July 11, 2026, 07:26:57 PM
I don't have a thermometer to hand in the 'train room', but in preparation for an open day today, I ran some trains successfully yesterday morning (Friday). The locos all come to rest in an isolated section ahead of each red signal, before I 'power off'.
On power up this morning (Saturday) a Class 47 immediately proceeded to run into the train in the next section. The cause? The rails had expanded so much that the isolated rail had come into contact with the 'live' bit! Guess I should have used Peco Insulated joiners!
ps 'running day very successful!
Kev E.
Title: Re: Temperature limit
Post by: Roy L S on July 11, 2026, 07:51:40 PM
Quote from: ntpntpntp on Today at 07:04:21 PM
Quote from: PLD on Today at 06:24:18 PMWhat some do panic over in hot weather is the expansion of track, but even those concerns are over-blown - the Coefficient of Expansion for Nickel Silver is 16 × 10-16 /1 degree C, so you need around a 64°C temperature change, for a 1 metre length of flexitrack to expand by 1mm!

That may be the theory based on the material properties, but believe me I've had fiddleyard track start to snake in my conservatory at 30 degrees (only in there for testing before a show), and in hot exhibition halls.  It's only loosely pinned compared to the fully glued and ballasted track on the scenic parts of the layout - that's never suffered.

Agreed, the track on our club test track in the Clubroom (in a metal portable office) got very wibbly wobbly in hot weather. Also it isn't just about temperature it is about extremes of temperature too I would say. I have had very few split gears in my Farish diesel fleet, but then the temperature in my modelling room (in the house) is comparatively stable and I reckon that is a factor.
Title: Re: Temperature limit
Post by: ntpntpntp on July 11, 2026, 09:28:09 PM
Quote from: ntpntpntp on Today at 07:04:21 PM... believe me I've had fiddleyard track start to snake in my conservatory at 30 degrees (only in there for testing before a show), and in hot exhibition halls.

Found this shot of expansion problems on my son's narrow gauge layout a few years ago.  Granted he was still mastering track laying and soldering etc. but clearly he forgot to leave any gap at all at this board joint and this was the result @ 36 degrees in our conservatory :(   This joint had been perfectly fine until then.

(https://www.ngaugeforum.co.uk/SMFN/gallery/160/5885-110726212359.jpeg) (https://www.ngaugeforum.co.uk/SMFN/index.php?action=gallery;sa=view&id=160793)

The layout's subsequently been dismantled as tbh it was too ambitious, and as parents we had to point out we would need the room sometimes, there would be nowhere to store the layout, and it would be too large to ever take to a show in our car!