Minimum curves for 7.25.

[Bryan Hardwick]

Hi everybody, I am new to this forum and I am considering running a railway around my garden. I am in the planning stage at present and waiting for some building work to be completed. I would like to ask what is considered to be the minimum usable curve radius for a running line (with speed restrictions if required). I would like to run a 0-4-0 (possibly with pony trucks or a bogie) but I would like it to be possible to run say a 6 wheeled locomotive. The ideal locomotive would be a Tinkabell.

Also what do people think the absolute minimum would be for say a shed area or sidings where speeds would be low.

Thanks in anticipation.

Cheers,
Bryan. ;D

[chris vine]

Hi Bryan,

I don't know if this is any help but I have a minimum radius of 30' for 7.25 gauge and the locomotive is a B1. I did leave a little extra clearance on the locomotive in a few places and I also spread the gauge on the curves by about 1/16" to help.

For running this is all really a bit too tight, I think 45' is normally the min recommended and 60' would be much better. There is a lot of friction on tight curves.....

Chris.

[chameleonrob]

As I understand it the curve radius should 20 times the longest fixed wheelbase
rob

[alanstepney]

The minimum recomended for 7 1/4" is 30 ft, ( www.alanstepney.info/page24.html )
but at slow speed, and with only a four coupled engine you could reduce that.
To what?
Around 20' but that might need a slight widening on the curves.
It may be possible to go down to 15ft, (I know someone who did so) but that tends to cause quite a lot of flange wear.

[Bryan Hardwick]

Well thank you very much for the replies gentlemen, I am afraid that it does mean I'll have to go for a 5" gauge railway as I am limited in space and 5" will give me enough lattitude.

Thanks again for your help.

[alanstepney]

Depending on exactly where you are in Dorset, 5" will also probably give you more choice of club tracks.