# Tightest curves on your railroad



## markoles (Jan 2, 2008)

Ward from the Golddawg Railroad in New Jersey paid us a visit during the open house event two Sundays ago. He went to all 9 of the open houses in the area, took pictures, and posted them on his webpage.
Ward's Pictures of the RR Museum of PA Garden RR Open house
I was surprised to see how many of the railroads are using R1 curves (the 4' diameter curves that come with starter sets). So it got me to thinking, I wonder how many on MLS are using tight curves, too. 

The follow up question to the initial poll is "Why do you use tight curves?" Is it space? Money? Both? 
Where do you use the tight curves/switches? 

I'm just curious, I guess. 

For me, the tightest I have on the line are the 8' diameter curves. I am using these in my storage yard because:
1. I already had them
2. I have space limitations in the storage yard.


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## East Broad Top (Dec 29, 2007)

Space limitations kept me to 5' radius (10' diameter) on my one reverse loop. I would love to have gone wider, but it would have eaten up too much of the yard. 

Later, 

K


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## aceinspp (Jan 2, 2008)

The only reason I ended up with some 8ft is that I did not think at the time I would need anything larger. As the new additions where added I than choose 10ft. Eventually I may be able to increase the diameter of my curves . Later RJD


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## DKRickman (Mar 25, 2008)

I had to respond ">10'" beause the only railroad I have access to at the moment is 12" to the foot.


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## Ward H (Jan 5, 2008)

When started I knew I wanted to run long passenger cars so my "not so local" train store, Nicholas Smith Trains suggested I stay with 10' dia. As I gained experance and expanded by putting in an upper level loop, I knew I would be running shorter equipment on that level so I went with 8' dia. May have a 6.5' thrown in here and there. 
When I redid my trackbed in the spring on the mainline, I have 10'dia or greater. Now I run my Blue Comet heavyweights a lot and I am glad I went with 10' and larger curves. 

My buddy went with the smaller dia curves and was able to fit in a lot more track in the same size space I have. For the trains he runs, short equpment pulling one or two cars, it works really well.


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## vsmith (Jan 2, 2008)

R1, and proudly anachronistic, the last of the mighty tighties...


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## Greg Elmassian (Jan 3, 2008)

10' because I read for years and determined that 8' was the absolute minimum for what I would run. I figured 10' would make things run better. It did. 

Regards, Greg


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## eatrains (Jan 2, 2008)

R1, mostly due to space. I've recently added a few R3s where I can.


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## Dan Pierce (Jan 2, 2008)

I did not respond as inside I have 4 foot diameter and outdoors I have 8 foot diameter. 

It is difficult to set up a poll for all variations. 

PS, I do use R1 switches for the freight sidings, R3 for passing sidings outdoors.


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## lurch (Dec 27, 2007)

Mine is a logging line so I really have not had too much trouble with 8ft min. Does slow some of my engines due to it is also on a grade. My Climax engine walks around it like it is nothing at all!


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## Warbonnet (Jan 3, 2008)

My tightest curve is 12' Radius. It is ok for what I run. Jake


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## jebouck (Jan 2, 2008)

My tightest curves are 15' diameter up to around 19' for the largest.
jb


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## Trains (Jan 2, 2008)

4 foot radius on old layout, 10 radius on new layout.


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## Bret W Tesson (Jan 6, 2008)

I started with an indoor ceiling layout using 8 ft diameter curves which worked pretty well. My outdoor layout also started with 8 ft diameter which I eventually replaced with minimum 10 ft. The USA streamliners and heavyweights like the bigger curves. I recently installed some 20 ft curves on a new section of layout and what a difference. The longer cars "look" much more realistic going around curves and are much less likely to derail. For my next loop I'm going to start each curve with a 20 ft section and then transition to a 15ft piece and finally 10 ft piece(s). I've read that "easing" a train into curves works much better than going straight to the planned minimum radius. It also doesn't take up as much space as a 20 ft diameter curve.


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## work4fil (Jan 4, 2008)

I am not that smart, I went for four foot diameter right off the bat, then found out it was too small. I then bought eight foot diameter, but am thinking 10 has to be my next minimum.


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## Greg Elmassian (Jan 3, 2008)

Mark, if you are still monitoring this thread, you should share the results with Lewis, he seems to believe that he needs to make locos for 4' diameter curves still. The poll is not huge, but interesting results, pretty much 3 to 1 on "large" curves... 

Regards, Greg


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## Dennis Paulson (Jan 2, 2008)

Posted By Greg Elmassian on 11/09/2008 10:01 PM
Mark, if you are still monitoring this thread, you should share the results with Lewis, he seems to believe that he needs to make locos for 4' diameter curves still. The poll is not huge, but interesting results, pretty much 3 to 1 on "large" curves... 

Regards, Greg


Yes by all means , with 52 people in the poll , its obvious that this reflects the large scale hobby needs for larger locomotives


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## Semper Vaporo (Jan 2, 2008)

Making an engine that runs on small radius curves does not preclude running that engine on large radius curves... but making an engine that only runs on large radius curves certainly excludes SALES to those that have small radius curves.


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## 6323 (Jan 17, 2008)

Using 8 foot diameter curves. Fits the equipment I currently have. 
Not sure if I'll go larger equipment, other than MAYBE an SD70MAC. 
I MIGHT also be able to go up to a 9 foot diameter curve, but I'd be pushing my clearance limits. 
And anything larger would require going completely around the house! 
Not sure the folks would appreciate that! Neighborhoods kids might though, if they saw train(s) running. 
My 2 cents worth. If that!


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## Greg Elmassian (Jan 3, 2008)

Yep Dennis, it's a small sample... no doubt. But the view by some is that it's completely the other way around... so maybe this would "spur" someone to investigate more deeply, and get some really good data. 

Regards, Greg


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## mhutson (Jan 2, 2008)

Mark, 
Mine has a minimum radius of 12', or 24' diameter. I run long standard gauge (1:29 scale) trains and they look good on big curves. 

Cheers, 
Matt 
M.P. 293 on the Rio Grande's Baldwin Branch


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## Dennis Paulson (Jan 2, 2008)

Yes Greg , we need someone in the spy sat program to confirm the info really , zooming in from space to confirm curve sizes . 
Pre curved track sales would not be a complete poll , because of modelers who buy flex track and bend their own large curves . 
I am sure that everyone , if it was possible for them , would use the large sweeping curves , and be able to operate anything available .


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## markoles (Jan 2, 2008)

Greg,

I am sure that Aristo and the others have either seen this data or have better data. I was just curious because of photos I saw of the garden railroad tour in my area. As far as I know, none of the other 8 garden railroaders are online or use this forum, but the photos indicate that at least two or three of them are using 4' diameter curves. Most were track powered, but I'm the only one using stainless. 

I was thinking about the above replies, and realized that I have given three starter sets to my neices and nephews, and that's all they've got. That'd be another three to add to the 4' reply section. Possibly soon to be four, as another cousin is thinking of getting an LGB set for his kids this year. 

Persoanlly, I don't see a problem with making the trains go around a tight cuve. LGB's articulated chasis for their Mikado worked pretty good. If any MTH 4-8-4 owners are reading, isn't that engine jointed between the #2 and #3 driver like the LGB mike?


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## tacfoley (Jan 3, 2008)

27 foot square backyard = maximum use of available space = 24ft diameter circle.

tac
www.ovgrs.org


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## tacfoley (Jan 3, 2008)

Mark - what MTH 4-8-4 loco is that? They make a 1/32nd Challenger [4-6-6-4] and a BIG BOY [4-8-8-4] as well asa Hudson [4-6-4] but I didn't know they made a Northern of any kind.

Best

tac
www.ovgrs.org


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## markoles (Jan 2, 2008)

Tac,

They make the SP Daylight locomotive, and supposedly have made variants for the WP version.


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## aceinspp (Jan 2, 2008)

Personally AC does not care as they are stuck in a time warp. Still thinking that 40 ft cars are the greatest.So they also think more folks use smaller radius than do bigger. I as Mark toured numerous RR this year and 99% had large curves. Look at what cars and locos USAT has brought out to fit the modern era. As the poll shows large radius is dominant but not that many responding. Later RJD


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## Marauderer (Jan 5, 2008)

Everything looks better on wide radius curves. They also run better.


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## Greg Elmassian (Jan 3, 2008)

The compromises that have to be made to a loco to operate on tight curves can be far reaching. 

For example, to make locos run on tight curves, one manufacturer makes the drivers slide side to side almost one inch total. Because of this side to side motion, it is impossible to put chuff magnets on the drivers. 

Also, the connecting rods have hinges in the linkage and huge holes for the crankpins. 

Because of all of this, it is impossible to drive the loco from the rods, so all the drivers have to be individually geared. 

There are far-reaching effects doing this. 

Making diesels work on tight curves makes them look funny when they have to pivot the pilot like lionel does on it's F units.... 

There are more impacts, and they affect the appearance, reliability, complexity, etc. 

So, making locos work on tight curves is not "free" nor does it make the loco "better" or more attractive in my opinion. 

Regards, Greg


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## Ted Doskaris (Oct 7, 2008)

For my circuitous under house layout, the main line track work consists of minimum 10 foot diameter sections eased with portions of 20 foot diameter sections leading into and out of the straight to curved areas, and the "S" bends also include a straight section of mostly 24 inches. Only my rail yard relies on 8 foot diameter curves to access it. 

-Ted


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## markoles (Jan 2, 2008)

Greg,

Because of all of this, it is impossible to drive the loco from the rods, so all the drivers have to be individually geared.

[//quote]
My LGB mike is hinged between the #2 and #3 driver. Motor drives a shaft that drives the #1 and #4 drivers, so 2 and 3 are propelled by the side rods. The cylinders also pivot a bit, not noticeable on large curves, but definetly on the 4' diameter curves. Still, has no problem going around a curve that tight, even if it looks terrible. I am pretty sure that the MTH 4-8-4 has a similar arrangement, but since I don't own one ore have ready access to one, can't say for sure.


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## Greg Elmassian (Jan 3, 2008)

I was kind of speaking of an Aristo steamer, they do not hinge the motor block, and until recently did not use any blind drivers on the mikado and mallet, for example. So all the side to side play required of the wheels forced the changes to the drive rods, and ultimately the powering system. 

It's just one example, as I said it "can be far reaching" .... CAN is the operative word, I did not say "is ALWAYS" for example. 

LGB has some clever engineering, and better tolerances in my opinion. 

Regards, Greg


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## lownote (Jan 3, 2008)

I have R3 curves as the smallest on my layout, except for a few R1 switches in a yard


But I don't agree that everything looks better on big curves. Big stuff does, sure. Mainline stuff, sure.. Narrow gage? less so. Those little LGB starter engines look fine on R1 curves. Mining locos, small branch lines, ore cars, logging consists---It seems to me there's plenty of room for nice looking, fun to operate garden railways at R1. 


Everybody attacks AC, but the people on this forum are just a subset of the larger hobby.


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## Dwight Ennis (Jan 2, 2008)

When in 2000 I built the Santa Cruz Lumber Co, I was limited by a very small yard, most of which is patio, I had a 2-3' wide planting strip around three sides to work with, so I decided a logging line seemed a natural choice here. I bought my first loco, a Bachmann Climax, and built a line running around three sides of the patio with automated reverse loops at each end. To fit the track in the allotted space, I went with R1 and R2 curves. 

As it turned out, even a Bachmann Shay (my second loco) wasn't happy running on this track due to some reverse R1 curves in the reverse loops. Then I got into live steam, and nothing would run on my layout except a Ruby, and it wasn't happy with my 4% grades. 

The SCLCo is long gone, torn out a few years ago. I built an elevated portable steam track which barely fits into my yard, even though it's only 11' x 19' overall (which demonstrates jut how small my yard really is). It does, however, allow me to run my steamers at home (when I have it set up), and has an inner loop with 8' dia. curves and an outer loop with 10' dia. curves.


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## GarryNCGRR (Jan 18, 2008)

When I started out in large scale I had decided I'd be going with 10 foot dia. curves as a minimum, but as I started drawing up my plans I jumped it up to 11 foot. I am using body mounted Kadees on all my engines and cars so the wider the turns the better. Would liked to have gone 12 , but had to go with some compromises, only so much space to work with, so you go with what fits best.


Garry NCGRR


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## snowshoe (Jan 2, 2008)

I am one of the few who run 6.5 curves. I chose this because it was the largest curve where all you need is 12 to make a circle. Anything larger I would have needed more to make a complete circle. thus brining the price up. I also never plan on running anything large. No intrest for the big locos and way too expensive for me. I also like the logging/industrial look. Most of these RR ran on tighter curves with smaller engines.


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## pdk (Jan 2, 2008)

Couldn't have said it better.
















Posted By lownote on 11/16/2008 9:42 AM
...I don't agree that everything looks better on big curves. Big stuff does, sure. Mainline stuff, sure.. Narrow gage? less so. Those little LGB starter engines look fine on R1 curves. Mining locos, small branch lines, ore cars, logging consists---It seems to me there's plenty of room for nice looking, fun to operate garden railways at R1.


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## todd55whit (Jan 2, 2008)

I have a few R1 turnouts left for some of the industrial sidings. When I first started out I had some 4' curves. After my first open house some years ago I realized I needed to do away with all of them. I run 1st generation diesels, all four axle. I can run on a 4' curve but it looks way better on a larger curve. Plus some visitors have a larger curve requirement. So if you want them to continue visiting and running their favorite locos ... had to improve. My mainlines were retrofitted to 8' and many of the sidings and the yard are now 5'. I still have R1 turnouts here and their, and have convered to AC wide radius on my mainline. I have had good results from running a 6.5' or a 5' curve with my R1's on sidings. Space is also a factor along with a learning curve. That's whats fun with this hobby your always improving things as time goes by.


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## ralphbrades (Jan 3, 2008)

Well as Mr Billington said when he was CME of the LBSC; "*Design* your locomotives for *your* railway" -and I have had the luxury of doing so, (twice!). The first layout was very restricted due to geology and geography so I had to design my locos to take 2 feet 6 inch radius curves. Now that I have a new house, (we have been here for 2 years), and a huge expanse of flat garden I can build bigger curves. The Gauge 3 part of the "circum garden loop" will use 8 feet 9 inch radius curves and the 16mm part of the track work will have a fruit garden loop with 5 feet radius curves. However I will still design my 16mm scale locos to take 2 feet 6 inch radius curves. 

Why did I choose 8 feet 9 inches?

This is because I am a lazy with my maths -yes it takes an EXACT number of track lengths to a 90 degree curves!!! The biggest fixed wheelbase that I could get around that curve is 4-6-4, (or 4-6-4 + 4-6-4)....



regards

ralph


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## Great Western (Jan 2, 2008)

8ft. diameter curves here, dictated by the size and disposition of the railroad. I don't think the poll is totally representative. It may be of some railroads in the USA, and Forum posters in particular, but many in the States and not just Europe do have small back yards. I think the three of us in the UK who have posted in this thread draw attention to that. A point, often I feel overlooked, is that American large scale manufacturers do export to Europe and other parts of the world and we don't have the luxury of your track sales - but we still buy from you.









The only track I am familiar with is Aristo and it does have quite a good range of lengths and curves available to the railroader. Probably others do as well but some are quite restrictive in their scope.


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## Big John (Jan 4, 2008)

I usuallly talk radius when refering to curved track. So 4' radius, 8' diameter are my smallest curves. I only run small steam engines depicting the narrow gauge era so tight curves would not be a problem. However, wide curves look Sooo much better. I have two main lines. One is 18' diameter and the other is 16 1/2' diameter. I use the tighter 8' diameter in my yards and entrances to my sidings.

Big John


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## Guest (Jan 1, 2009)

I voted based on my outdoor layout which has 10' minimum curve diameter. My basement table layout has 4' and 5' curves in order to fit within my 8' X 12' space.


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## pk (Jul 6, 2008)

Tightest for me is 20' 

Tightest out on the main is 24' 

Regards, 
pk


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## Bill C. (Jan 2, 2008)

I started out with four-foot diameter curves more than ten years ago but now my main line has eight-foot diameter curves. Maybe I should have called it the Darwin Garden Railway. Anyway, the R1 curves are still there on the sidings. Good thing I like small locomotives and rolling stock.


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