Radius question


URI

URI

Member
Did a search of the forum and net, but I come up empty on radius charts. I'm trying to find out what the minimum radius are for 3', 3 1/2' and 4' spaces for getting a train turned around.

Any advice where to get this information, or if anyone knows what those radius would be. Thanks.
 
Minimum radiues...

Well Atlas makes 9 3/4" radius track. (24.7cm)
Kato makes 8 9/16" radius track. (21.7cm)
Peco has 9" radius track. (22.8cm)

However, on my home layout, the width is 64cm and I use a minimum radius of 28cm (11")

I chose that minimum because I run 1880-1900 equipment. So a maximum of 50' cars. If I were running modern equipment, while they would handle the 28cm radius, they do not look pretty doing it. :D I woud pick the 48cm (19") just for the visual effect.
 
Depends on equipment quite a bit. An S1 switcher does not need the same turning radius that a Big Boy needs. It also depends on your scale HO scale needs a larger radius than N scale.

In other words we need more information.

Tell us more about what you want to do.
 
I'm doing n scale and want to run intermodel with Dash 9's. I'm hoping in the future that the ES44's are made. So I'm just trying to decide a few things on my project. Not familiar with "space to radius". So I was trying to find out the radius that would fit in 3, 3 1/2, and 4ft wide spaces.
 
URI, I'm still a little bit confused. Are you looking for the maximum radius of a loop that will fit in a certain width? If so, the math is simple. Let's say you have a 36"-wide area and want to leave 2" space between the track center and the edge of the layout. The maximum loop diameter would be 32". Divide by 2 to get the radius, 16" in this case. As Will and Chip point out, the minimum radius depends on the equipment you are running.
 
Steve said it well

Take your width of your layout, subtract 4" (2" on each side of the layout so the tracks are not on the edge if the board, you dont want them falling off the layout....), and then divide by 2.

You can also multiply the radius if you have to have a minimum for longer equipment. Say you need a minimum of 22" radius, multiply this by 2 and add 4", you get 48" (this includes 2" of clearance of each side of the table)

im not all that familiar with N scale, I model intermodal in HO scale, but dash 9's and intermodal double stacks, 89' piggy back flats...... require large radius.

Sometimes on the Manufacture's web site they will say the minimum radius required for longer rolling stock and long 6-axle locos. Im no expert in N scale, but if you are running intermodal trains, i would do the largest possible radius you could possibly do for smooth running. Not only will you have less problems, it will also look much better when those long trains are running around the broad curves.....

If you can do a 48" space for your train to turn around, i think you would be much better off, this would give you a radius of 22" in N scale, and for N scale, that is a very nice and large radius.... I would suggest going for that, with a 22" radius in N scale you wont have to worry about how long of cars you run and if they will be able to navigate the turns well.

Hope this helps
 
Fishplate and Trucklover,
I guess I was a bit unclear in trying to get out the question, but you guys have answered exactly what I was looking for. Thank you for that. I will do the 48" width to gain the 22" radius. When you've been out of the hobby for a while, you tend to forget stuff. Myself anyway. Been reading and reading and wnat everything in order before laying any track.

Again, I thank everyone on helping me get my questions answered, this forum really helps.
 
Glad we could help URI :D

Might i suggest that you use Flex Track when you lay those 22" curves as well. Flex Track is alot better then sectional track, besides im not sure if 22" radius sectional track is available in N scale.

Flex Track is the best way to lay track on your layout, as it can be used for both curves and straights, and it will make your layout have alot less connections, which will be better for power flow :D
 
Very interesting thread. I understand the need for looks, however I don't have much room and prefer to maximize trackage... Hence what is the lowest radius a Dash 9 (my longest piece of rolling stock) can accept? 11" Radius, 10" maybe? What about an autorack or a GP38? The reason I ask is that the recommended radius are rather conservative, i.e. I manged to run my steam engine on 15" Radius in HO when 18" was required.

Thank you!
 
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I wouldn't run an autorack on anything less than 15" radius. Preferrably more, it looks wierd, and you would probably have derailment issues.
 
Russian said:
Very interesting thread. I understand the need for looks, however I don't have much room and prefer to maximize trackage... Hence what is the lowest radius a Dash 9 (my longest piece of rolling stock) can accept? 11" Radius, 10" maybe? What about an autorack or a GP38? The reason I ask is that the recommended radius are rather conservative, i.e. I manged to run my steam engine on 15" Radius in HO when 18" was required.

Thank you!
Click to expand...

My sd 60s and u50 ran well on 9 3/4" radius but looked like hell! if you need to run on tight radius curves....Hide the curves in tunnels! and make sure you get more than 1 3/4" between curves and make sure you have a easment curves too! As for the Auto racks no way! any thing over 70' will have major clearence problems!
 
Thanks for the help guys. You've given me much to think about. Definitely no autoracks LOL, besides one can have two other cars in their place. The local tramp job always gives two numbers when coming in the yards for the same reason, 14 cars, length 20 with 6 autos!

vato loco said:
My sd 60s and u50 ran well on 9 3/4" radius but looked like hell! ...any thing over 70' will have major clearence problems!
Click to expand...
Being picky now, a SD60 is [FONT=trebuchet ms, arial, helvetica]71 feet 2 inches long, SD60M even longer @ 74ft. Dash 9 is [/FONT]73 ft 2 in.
 
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