Min Radii of Bachmann HO locomotive (Steam and diesel)

[Railroadjoe]

What is the minimum radii of Bachmann's HO locomotives? I have never seem that Spec in any of the Locomotive descriptions.

Thanks

Railroadjoe

[Jhanecker2]

It depends on the loco ,  however  since  15" radius is the smallest that would be the absolute minimum . Most trainsets are sold with 18" radius track  making that the defacto minimum for most  small & regular sized diesels and  and  probably  for  0-4-0  to 4-8-0 steamlocos . Anything with a longer wheel base such as a 4-8-4 comes with  22" radius track as a minimum. Also the length of the rolling stock is also a determining  factor .  Longer passenger cars and autotransporter cars as well as container & extra heavy weight flatcars also require much larger radius curves to function and to look appropriate .   J2

[ABC]

There are several different minimums. Minimum required for it to run without trouble 75% of the time. Minimum required to run without trouble 100% of the time. And minimum required not to have a large overhang. All of these vary with each individual locomotive.
24 inch radius curves are pretty safe for most locomotives, freight and passenger cars. 15 inch radius should not be used unless it is absolutely necessary and if used no rolling stock should exceed 40 feet and no 6+ axle diesels, or steam engines larger than a 0-4-0. 
I'll check my catalog to see what Bachmann says for each loco.

[ABC]

Here is a list of everything
Thomas, Toby, Mavis, Salty, Bill, Ben & Percy 15"
James, Gordon, Emily, Spencer, Donald, Douglas, Edward & Henry 18"
4-2-0 Pegasus 18"
0-4-0 Dewitt Clinton 15"
4-8-4 22"
2-8-4 22"
4-8-2 22"
2-10-4 22"
2-10-2 22"
2-8-0 18"
2-6-2, 2-6-0, 0-6-0 & 0-6-0T 18"
4-4-0 (both) 18"
DDA40X 22"
GP50, GP40, GP38-2, GP35, GP30, GP7 18"
SD40-2, E33 22"
RF-16 Shark, B23/30-7, U boat, H15/16-44, Ft-A/B, GE70 ton, E60CP 18"
GE 44 ton, MDT plymouth, 15"
PCC, Brill trolley, cable car, gandy dancer, high railer (MOWs) 15" radius

[Pacific Northern]

Here is a list of everything
Thomas, Toby, Mavis, Salty, Bill, Ben & Percy 15"
James, Gordon, Emily, Spencer, Donald, Douglas, Edward & Henry 18"
4-2-0 Pegasus 18"
0-4-0 Dewitt Clinton 15"
4-8-4 22"
2-8-4 22"
4-8-2 22"
2-10-4 22"
2-10-2 22"
2-8-0 18"
2-6-2, 2-6-0, 0-6-0 & 0-6-0T 18"
4-4-0 (both) 18"
DDA40X 22"
GP50, GP40, GP38-2, GP35, GP30, GP7 18"
SD40-2, E33 22"
RF-16 Shark, B23/30-7, U boat, H15/16-44, Ft-A/B, GE70 ton, E60CP 18"
GE 44 ton, MDT plymouth, 15"
PCC, Brill trolley, cable car, gandy dancer, high railer (MOWs) 15" radius

The Shay is ?

[ABC]

Note Bachmann says it "performs best" on these radius curves and it is not the absolute minimum.
Climax 22"
Shay 18"
2-10-0 22"
SD-45 22"
8-40C(W) 22"

[Railroadjoe]

Thank You

Railroadjoe

[bobwrgt]

Alot of engines listed for 22in radius will work just fine on 18in.  YOU MUST HAVE GOOD TRACK WORK THAT IS LEVEL AND SMOOTH. I run the following on 18in all the time at all speeds.
8-40CW
8-40c
SD45,s
Heavy and light mountains  4-8-4
2-10-0 's
2-10-2 Santa Fe

On the 6 axel diesel you may need a long shank coupler to keep from pulling the first freight car off on the curves. You can also just make sure the first car has a long shank coupler.

Bob

[ABC]

Like I said before, it is what Bachmann determined to be the radius the loco will perform best on, not the absolute minimum. Bachmann locos are also highly variable I have at least one of the following that does not run well on 18" radius (composed of Bachmann NS E-Z Track).
4-8-4
SD-45
2-8-4
4-8-2
2-10-0
2-10-2

[Pacific Northern]

I too have run the Spectrum 2-10-0, 2-10-2, Light and Heavy Mountain 4-8-2's and 2-6-6-2's on a layout with 18" radius track without any derailments at all.

Having said that, there have been a number of postings of members who have had trouble with the aforementioned engines on 18" track. I do not think that all of the problems were due to the track not being properly laid. I would assume that some of these engines were manufactured with tighter tolerances pertaining to the wheel sets than would be considered typical.

Some posters have even had problems with the 2-8-0 not running on 18", that I would suspect could well be a track-work issue.

The only engine I have that demands 22" radius track to run is the Spectrum J 4-8-4. That is not surprising since it is quite a large engine.

I agree that having layouts with larger radius curves adds to the realism and certainly looks better, but not all have the room for larger layouts.

[bobwrgt]

If your engine won't run on 18in radius track there are several things that come into play.
Check the track and wheels on the engine. Are they in gauge.
Use the correct hole in the steam engine draw bar and check to see where the wires are coming from the tender.
Are the coulper bars centered  or hitting the ties or rail.
The track also needs to be level (side to side) or elevated on the outside only. No
humps in the middle.
Are the wires inside the engine restricting the movement of the truck on diesel engines.
Are the drive rods on a stream engine bent restricting side movement of the drivers.

These are only a few reasons why some people have trouble running on 18in radius.

Bob

[ABC]

Well my track and wheels are all in gauge, no coupler problems (I have removed them just to rule them out). My track was a 36" diameter circle made of E-Z track on a level board. I have tried running them with both holes (didn't matter). The drive rods were not bent. I checked the wires on the SD-45 and could find nothing. It isn't because of any of these reasons; I think it just has to do with the variability in the production of these locos.
Ultimately, there are some locos that for some reason won't run on 18" radius and you can't do anything about it. I sent one in once when I had to send some others in that had defects and Bachmann checked it out and couldn't find anything and could not get it to run on 18" radius.

[Pacific Northern]

Well my track and wheels are all in gauge, no coupler problems (I have removed them just to rule them out). My track was a 36" diameter circle made of E-Z track on a level board. I have tried running them with both holes (didn't matter). The drive rods were not bent. I checked the wires on the SD-45 and could find nothing. It isn't because of any of these reasons; I think it just has to do with the variability in the production of these locos.
Ultimately, there are some locos that for some reason won't run on 18" radius and you can't do anything about it. I sent one in once when I had to send some others in that had defects and Bachmann checked it out and couldn't find anything and could not get it to run on 18" radius.

Which steam engine are you referring to? (both holes, drive rods) that would not run on 36" radius?

[ABC]

I never said anything about 36" radius, I did however say 36" diameter, which is the same thing as 18" radius.

[Pacific Northern]

I never said anything about 36" radius, I did however say 36" diameter, which is the same thing as  18" radius

I stand corrected. 18" radius it is.

Now what was the Spectrum steam engine (s) you are refering to.?