Min radius for switchers? HO scale

[Anonymous]

HO scale, 4 axle diesel switchers, SW's, MP's, etc? I know 18" is the recommended min for most 4 axle road engines like Geeps, but I was wondering if an SW or MP pushing a couple 50' boxcars could squeeze through an industrial area with a couple of 15" radius curves? Very slow speeds, and no more than a 90* turn.

Also, I know I'm looking for trouble asking this, but, what about a 15" radius S curve with no easements? (two opposing 30* curves making up the S). There's one place I'd like to squeeze in an extra siding to hold one car, but it would require a very tight S curve. The curves would be on dead end spurs, and never see anything larger than an SW or MP, and modern boxcars (nothing longer than 50'-60', never anything longer, and definitely no 80' autoparts boxcars)

[rolleiman]

It isn't really the speed of the train but whether or not it'll stay coupled.. I'm certain the loco will handle a 15" radius but staying coupled to a 50' box car with body mounted couplers without pushing the car off the track may be a stretch.. I don't know that it is, it just May be.. With respect to the 15" R S curve, try it if you like but I would recommend having it broken up by at least one car length if at all possible. No reason you can't lay out some track in a temp setup and give it a try.. If it works for you, have at it..

Good luck,
Jeff

[Jetrock]

15" radius is just fine for four-axle switchers (or roadswitchers--my Geep does fine on 15" radius but groans a bit on 12" curves) pulling (or even pushing) 50'-60' cars. An S-curve will cause problems, especially with tighter radii--if there is any way to avoid or reduce the S-curve, through easements or bumping it up to 18" radius, you'll save yourself some heartache.

Be careful with your trackwork, and go slow.

[challenger3802]

i've got 15" curves on my layout, the switchers handle them no problem, and most cars under 60' will handle them too. However, the 65' Cars come striaght off on all the curves (the rest are 18").

Ian

[Anonymous]

Well since the track plan is still in software form (RightTrack 7.0), I played with it a bit yesterday and got rid of the 15" S curve, and replaced it with an 18" S curve, with a 5" easement (straightaway) between the two curves. Still a bit tighter than the optimum S curve design, but I think it'll do. Of the other three curves, I got rid of one with the S curve, widened another to 18", and shortened the last one to a 15" curve, only about 45 degrees in arc.

[IRONROOSTER]

The NMRA has a page of recommended radius for different classes of equipment. http://www.nmra.org/standards/rp-11.html

If you follow this, you should have no trouble. I would recommend you experiment with your actual equipment before using sharper curves.

Enjoy
Paul