Large Scale Central

Minimum Radius requirements

I’ve been posting A LOT but I appreciate the response. I run LGB on R1, R2, & R3 track. Most other G-scale brands require a minum R2 radius to operate without derailing. I was interested in adding a USAT R22107 NYC Switcher to my layout (and add “P&LE” markings). Anyway, I was wondering how to determine the minimum track radius required for non-LGB loco’s? Does the “R2” in “R22107” identify that the requirement is a minimum R2 track radius?

Jay Briscoe said: Does the “R2” in “R22107” identify that the requirement is a minimum R2 track radius?

No it does not indicate the radius.
The “R22107” is a stock number for USA trains

R22107 SANTA FE GP-9

( see attached file) http://www.usatgscalegroup.com/phpbb/download/file.php?id=168

This engine likes 8’ curves (4’ radius) when pulling items behind it. It will negotiate the smaller curves.

I hope this was helpfull.

LGB R2 is roughly 5’ diameter, Piko R2 I beleive is wider, closer to 6’ diameter but I cant say for certain. The USA NW2 switcher will work fine on LGB R2. IIRC the USA starter set that comes with the NW2 Switcher actually comes with R1 track.

LGB

R1 = 600mm radius

R2 = 780mm

R3 = 1195mm

R5 = 2320mm

PIKO

R1 = 600mm

R3 = 921.5mm

R5 = 1243mm

R7 = 1565mm

TrainLine45 (no R designation)

900mm

1200mm

The USAT site normally lists the minimum radius for it’s locos.

Greg

I have a USAT NW2 and similar S4 and they will go around a R1 or 4 foot diameter track but wider is better. Both engines will also make it through the tighter switches like a 12000 LGB series.

Sometimes it is tough to go by the builders minimum curve recomendation. I have several Bachmann Spectrum engines and they say 8’ diameter curve minimum but I have run them through as little as 4’ diameter. They don’t like it and look silly due to overhang but they make it.

4 wheel trucks are more forgiving than 6 wheel ones. Level track is important.