Underbridge

[Bandit Mick]

Hello everyone - hope you've all had a modeltastic Christmas. A bit of help please. I model in OO gauge and want to build a single track stone underbridge. I found Melcalfe's dimensions but the arch seems a bit wide at 122mm. Does anyone know the average dimension of the bottom of an arch i.e. across the track? Any help will be gratefully received.

[Walkingthedog]

You can always adapt the Metcalfe to fit. I guess they are as wide as is necessary to take the track and fit the location. Can’t imagine there is a standard size.

[Bandit Mick]

Thank you WTD.

[Walkingthedog]

I have the Metacalfe viaduct which is for single track but I adapted it to take two tracks.

All you need is a Stanley knife and a pack of Elastoplasts.

[RAF96]

Plasters for the knife wielder Brian, not to clag the cardboard bits together.

I would think size and profile of tunnel entrances, etc were decided locally to accord with the loading gauge as presented by the road angle entering/leaving said orifice, or in the case of a viaduct the load bearing of local build materials versus the gap to be spanned.

No doubt the Engineers had a basic out of the box design which they fettled for local conditions.

Rob

[Mountain Goat]

If you model the B.R. period and have made a bridge or tunnel that is of a narrow nature, adding some "Limited Clearance" red and white boards will add a little realism to the scene.

[AustralianLMS]

Does this help?