SHOULD I LEAVE A GAP BETWEEN MY RAILS ?

[The Sligo Rover]

Advice required please, I am just about to start my track laying, should I leave a gap between the rails and if so how big please?
Would the thickness of the cardboard of a corn flakes packet be about right? My layout will be subject to extremes of heat and cold due to its location.
What do other people do?

[Steve M]

Yes there should be an expansion gap. Generally the gap should be about the thickness of a credit card but take into account the ambient temperature - if it’s cold the rails will need a little more of a gap to allow for more expansion when the weather improves.

[Brian]

As you're UK based then the ambient air temperature is going to be around 8C to 12C currently. So when summer comes the temperature can rise to 25C to 30C (Hopefully!) Therefore if no gap is left when track is laid when its cool it will expand and cause the rail to buckle and possibly pop out of the moulded plastic chairs!

So I highly recommend cutting up some (up to 1.0mm thick) card - Post card etc into just over track widths and inserting a strip into each joint so as the card sits on top of the fishplate (rail joiner) This will give what should be adequate expansion gap. Once all that area of track is securely pinned down then the card is removed.

[The Sligo Rover]

Thank you.

[Chuffchuff]

Just wondering if the above is per length of flexi track or medium lengths ( sort of ) of set track?

I have in the back of my mind soldering two or three sections of set track together to stabilise electrical connection and make the joints more stable. Length would be about one meter same length as flexitrack with an tight/ loose fishplate at each end to allow thermal movement from the track and next length of track.

It's an attic layout so gets hot and cool, rather than cold.

Didn't want to reinvent the wheel,if others had gone down the same route and ended with problems.

Please excuse mixed metaphors

Rgds

[Walkingthedog]

Leave a gap between every section of track no matter what length. Never solder lengths together no matter what length.

Solder a short length of flexible wire between each section to bridge the fishplate if necessary, or a wire from each section to the power supply.

[LC&DR]

Generally speaking I would agree with WTD that for set track, which provided it has been pinned down and the rail joiners are tight and correctly placed should be excellent for electrical continuity.

I have insulated my attic above and below, but in high summer it can still get very hot up there, it is better in winter since I did it but a long spell of cold weather can still create a chill.

A further consideration has to be whether at some point in future you may wish to make changes. It becomes much more difficult if you solder the joints.

[Chuffchuff]

Thanks for your advice. I suppose a further consideration that flextrack has more slippage between the rails and chairs allowing some movement. Set track being ridged and generally in shorter sections expands as a unit of rail and chairs, but movement can be accomplished by moving smaller sections.

My thinking is probably badly explained above, but hopefully you get my gist!

Rgds

[Walkingthedog]

On my old loft layout I had about 3 ft of flexi between two sets of points. I didn’t have any gap. One hot summer the piece of flexi looked like a long 'S' over an inch each side of the centreline.