Minimum Radius Question Answers

[Len]

It seems like, "What's the minimum radius curve for loco XYZ?", gets asked a lot around here. So I went through the current 'On-Line Store' offerings and made a list to put in one spot. Admins, feel free to move to the FAQ area if you think it's appropriate.

Minimum Recommended Curve List for Bachmann Locomotives
Note: Few of these locomotives look good operating on the 'Minimum Recommended Curve'. In some cases the overhang looks completely rediculous, and can result in collisions with scenary. Locomotives look better on curves larger than the 'Minimum Recommended', and will generally operate better due to less side forces on the mechanism.

Steam
0-6-0 USRA - 18" Radius
0-6-0T Porter - 18" Radius
2-6-0 Mogul - 18" Radius
2-6-2 Prairie - 18" Radius
2-8-0 Consolidation - 18" Radius
2-8-2 Light Mikado - 18" Radius
2-8-4 Berkshire - 22" Radius
4-4-0 American - 18" Radius
4-6-0 Ten Wheeler - 18" Radius
4-6-2 USRA Light Pacific - 18" Radius
4-6-2 K4 Pacific - 22" Radius
4-8-4 Northern/GS4/J Class - 22" Radius (a.k.a. Niagra/Santa Fe/Greenbrier/Western/Dixies/etc., etc.)
50-Ton 2-Truck Climax - 15" Radius

Diesel
ALCO FA/FB-2 - 18" Radius
ALCO RS-3 - 18" Radius
ALCO S-4 - 18" Radius
EMD DD40AX - 22" Radius
EMD E7A - 22" Radius
EMD F7A/B - 18" Radius
EMD GP7 - 18" Radius
EMD GP9 - 18" Radius
EMD GP30 - 18" Radius
EMD GP38-2 - 18" Radius
EMD GP40 - 18" Radius
EMD GP50 - 18" Radius
EMD SD40-2 - 18" Radius
EMD SD70ACe - 22" Radius
GE 44-Ton - 15" Radius
GE 70-Ton - 18" Radius
GE ES44AC - 22" Radius

Electric
ACS-64 - 22" Radius
GG-1 - 22" Radius

Streetcars
PCC Streetcar - 15" Radius
Cable Car - 15" Radius

Len

[Hunt]

FYI -

Steam
50-Ton Two-Truck Climax -
      per Bachmann Trains: Performs best on 15" radius curves or greater.

[Len]

Hunt - Thanks. Updated the list for those who want to copy & paste into a text file for their own reference.

Len

[ebtnut]

The Peter Witt trolley will go around 8" curves.  The Birney will do at least 6" curves. 

[Len]

Note that the list is of Bachmann's 'Minimum Recommended' curves, not what the locos may actually negotiate.

That said, the info gained by experience on the trolleys is helpful for those that may be contemplating street running.

Len

[Hunt]

The Bachmann "Performs best on radius 15" curves or greater" info for Streetcars and short wheel base locomotives that can run on lesser is because 15" radius curve is the smallest Bachmann manufacturers in HO.

[Trainman203]

Will my EM 1 run on 9" radius?  😂😂😂

[Len]

The Bachmann "Performs best on radius 15" curves or greater" info for Streetcars and short wheel base locomotives that can run on lesser is because 15" radius curve is the smallest Bachmann manufacturers in HO.

I don't have all those locos to test for actual minimums, and it seems like every time the question gets asked the answer points them to the on-line store to get the answer. That's why I just collected 'Bachmann's Recommended Minimum' curve info. I'm sure the answer to, "How tight a curve can it actually take?", is out there if you look hard enough. But that wasn't the intent of the list.

Len

[Len]

For those who really want to know how tight a curve their locos can handle, you could always build a "Death Spiral" to test them with...



This is a diagram of one I built years ago using odds and sods of track I had laying around. The curves tighter than the 360mm R1 are actually flex track. It was easier to lay them out in the software as sectional track. The entire thing could be done with flex track. It helps to mark the start and end of each radius, along with it's size, directly on the platform. Each radius is a 90deg turn into the next size. The straight section leading into the 24" radius is to make getting locos on the track easier.

Len

[indian_hills_r_r]

I am glad this question came up. I have a old Bachmann trolley (DC) that I am going to add to my new layout. it will do a point to point to point to point run though town and I was wondering just how small of a radius it would take. because I am running down the middle of the streets.  it only has two axles. I see now that it is possible to go as small as 6". this trolley also has a working pantograph which I found to really neat for my layout. the layout is dcc but this trolley will run dc so I don't have to swap over to dcc. thanks for the info