O Gauge B-set Minimum Radius?

[mahoganydog]

Anyone know if these can cope with the Peco 2nd radius curves ST-725?

Thanks

[gppsoftware]

On the B set box is says 'suitable for R2 40.5 inches'. That's 3 foot 4.5 inches. Basically 3.5 feet.

Mind you, at that tight radius, they wouldn't look very realistic!

I put them on a 5 foot radius curve to test them and while the negotiate it without a problem, I'd say that even at that radius, they are right on the boundary of realism and non-realism!

[Bigmet]

And any O gauge curve scaling under ten chains radius (that's 4.6 metres or 15 feet radius or smaller) with passenger services running, must have a check rail and will be subject to a severe speed limit. I don't know what the curve limit was for UK coach stock with screwlink couplers and side buffers, but steam era coaches with the knuckle coupler and Pullman gangway combination were typically limited to six chains radius.

(As for the real curvature of running lines allowing operation even at a modest speed such as 70mph, this is a standing problem for all railway modellers in practically any scale. Even in Z you are looking at a 5 metre radius for that true scale for half mile radius curve sweeping through the countryside.)

[gppsoftware]

And any O gauge curve scaling under ten chains radius (that's 4.6 metres or 15 feet radius or smaller) with passenger services running, must have a check rail and will be subject to a severe speed limit. I don't know what the curve limit was for UK coach stock with screwlink couplers and side buffers, but steam era coaches with the knuckle coupler and Pullman gangway combination were typically limited to six chains radius.

(As for the real curvature of running lines allowing operation even at a modest speed such as 70mph, this is a standing problem for all railway modellers in practically any scale. Even in Z you are looking at a 5 metre radius for that true scale for half mile radius curve sweeping through the countryside.)

I think the reality is that virtually all modellers have curves which would:

- Have a continuous check rail
- Require foot escort to check that wheels don't jump rails
- Be severely speed restricted to 15mph

Yet they run HST's at top speed around them!

With the exception of those of us with minimum 5 foot radius curves, the vast majority of layouts have curve radii which are way below the minimum limits on the prototype and to that end, cannot be scaled.