# TEST TRACK - various curves



## SD90WLMT (Feb 16, 2010)

Some times it is easier to be knowledgeable than just guess at something.
While everyone is aware I'm not building the typical layout size wise, I do dabble in a variety of projects for others. This forces me to stay ahead of the curve on design projects, and as such I finally needed a curved test track to plan ahead and ensure what I build will fit and work for My friends on their layouts.

Here is My new test track, built on plywood. I store it indoors, while bringing it outside to use as needed.

4 curves provide flexibility in design needs to try different approaches. Also this works great in a step down approach to find that curve that works best, yet is the limit for a piece of equipment.

I built 12ft, 10ft, 8ft, & 6ft Radius curves. These cover 90% of what I or friends run on.

The track used is flex track, installed using a huge temporary protractor to create smooth line work, then screwed to the plywood base.










Using a SD45 loco, coupled to a USAT 50 ft box car

Over hang on a 12 ft R 










Over hang on smaller 6 ft R










Using this curved track has helped Me on many projects I have been working on, knowing what fits and how much clearances may be existing or needed on a project.

Dirk
DMSRy.


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## ewarhol (Mar 3, 2014)

I'm gonna have to think of building something like that.

But for now, my tightest radius is 4.5' (9' diameter). If I can make it work now, then I know it will work on my future dream layout where the radii/diameters will be larger.

What kind of track is that? SVRR? Code 250?


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## SD90WLMT (Feb 16, 2010)

Llagas Creek, aluminum rail - code 250. Flex


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## fyrekop (Sep 20, 2011)

Dirk,
I have some 4' R pieces of brass Aristo if you want to make a "tighter" turn on another piece of plywood. I think my tightest curve is 5' R so there will be some hang over if you bring those larger engines.
Alan


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## SD90WLMT (Feb 16, 2010)

I'll have to pick n choose which large locos can swing trucks tight nuff for your layout...!
Many are limited down to 8 ft radius...as tight as they will safely run..

Well have to work up a list of power do's n don't see for my stuff...
I fully expect my steam power should not be as restrictive tho.


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## SD90WLMT (Feb 16, 2010)

I do need to possibly build a 5 ft R curve..for reference..in the future some time..


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## fyrekop (Sep 20, 2011)

Quick Oops. No curves less than 5' R since I'm building to take that Live Steam Mikado and that is min 8.5 D


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## Garratt (Sep 15, 2012)

I'm glad you marked both radius and diameter.
Nothing worse than a tool that stooges you.... 

Andrew


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## SD90WLMT (Feb 16, 2010)

Yea...... Amazing how many are baffled in G by what curves are being used...

Like learning all over again...

Tried to help everyone... Brought about by my own huge curves for my layout..I always state both R & D..just to be "clear"...
Thanks Andrew


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## Garratt (Sep 15, 2012)

Fitting it in the tool box wiill be tricky. 
Simple enough to hang it on the wall though. Easier than making 'helix mountain' for testing.

Andrew


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## East Broad Top (Dec 29, 2007)

Is this more for checking overhang and things of that nature? When you're starting at 6' radius (12' diameter), that's already well within the comfort zone of 95% of the models on the market in terms of fitting around them. Most commercial diesels (even the big Dash-9s, etc.) can handle 4' radius. Whether they look good _doing _so is a different matter, but they'll at least fit. 

Later,

K


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## SD90WLMT (Feb 16, 2010)

I built this because I dabble in too many unknowns as far as my loco or long HW cars go..!
I wanted to know for certain what the results of my ideas and actual efforts turned into...just in case I had to make adjustemts to them.
For my personal use and layout...I'm rather happy to run at a 10ft R...
Having some of my work actually be as I dream about..while running on a 8ft R is more like icing on the cake...I find that what I build for friends needs to fit this 8ft R curve..so I make changes accordingly... And they are just as happy..
Think of it as insurance ... Since I do not commonly run the average layout most build.

Dirk


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## John J (Dec 29, 2007)

Are those Factory curves or are they curves you bent with a bender?

If you bent them How did you figure it out?

I have a jig I made in the concrete floor of my work area for a 10 15 and 20 foot curve using a 5 ft chain a 7.5 ft chain and a 20 ft chain to draw a arch on the floor then I drilled holes every 1ft along the arch. I bend my steel to fit the arch. That is how I make my forms for my concrete road bed. 

JJ


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## SD90WLMT (Feb 16, 2010)

Morning JJ...
I used easy to work with - Flex track..no bender..and its aluminum rail.
I made a simple..temporary protractor to swing a long tape measure..making ink marks often on the ply....followed them with track..installed same and double checked afterwards. Eyeballed for smoothness...tightened screws...laid out next smaller curve to suit...pretty easy..
Stores indoors..out of rain..or sunlite..!
ThX...


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## John J (Dec 29, 2007)

SD90WLMT said:


> Morning JJ...
> I used easy to work with - Flex track..no bender..and its aluminum rail.
> I made a simple..temporary protractor to swing a long tape measure..making ink marks often on the ply....followed them with track..installed same and double checked afterwards. Eyeballed for smoothness...tightened screws...laid out next smaller curve to suit...pretty easy..
> Stores indoors..out of rain..or sunlite..!
> ThX...



Thanks for your response. That is about what I did for my forms. 

I like the idea of a test track system.

Lets you know what you can do on your layout before it turns into a problem 

JJ


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## SD90WLMT (Feb 16, 2010)

Using the test curves..... And notes I glanced at yesterday...I noted I am building my recent long H.W. cars to fit not less than 10 ft radius curves....
Using the curve with a car placed on the desired segment... Has allowed me to predetermine truck pivot and clearances to build the under frame details to..

I use the curves more than I expected... 

SD


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