Smallest Figure 8 using Kato Unitrack

I only have a 44" x 20" space to work it. I would like to make a figure 8 in that space. I do not need to use the whole 44" length, it can be shorter, but it cannot be wider than 20". Is this possible?

I am looking at Kato Unitrack 20-170 & 20-171. Kato claims it has the smallest radius available in their tracks. It is an 8" radius.

Could I use these tracks for the circle part of my figure 8?

If so, how many would I need to make this circle fit in a 20" wide space?

How many straight tracks would I need to complete the figure 8?

The 20-320 crossing would have to be used.

I know I can only run a short locomotive on this track, but that is what I will be running on it.

seeing as you’re talking about an 8" radius, I am going to assume you are modelling in N Scale.

If the sections work out like they do in HO, 6 will create a half-circle (180º). If my figuring is right… you should need like 8 or 9 sections per side to make the round parts for the figure-8.

Yes I am using N scale.

Now when you say 8 or 9 would make a circle are you talking about using the 20-170 or the 20-171 tracks?

20-171 is the short version of the 8" radius tracks

20-170 is the long version of the 8" radius tracks, which I believe to equal 3 of the 20-171 track. Right?

yes, I mean the full section tracks, not the 1/3 section tracks.

Okay I have the circle. Now how many straight tracks will I need? Which size do I buy? I really need to know the number of the track to buy.

ie; Kato 20-100

Those tracks will have to make an 18" diameter circle so that the circle would fit in my 20" space. So now I will draw an 18" circle and see how large it is and try to figure out exactly how many tracks I will need.

I’m not sure as to the straight tracks - it depends on their length. as you have it right now, you have two 18" radius curves for a total of 36" taken up - so you really only have about 8" worth of free space (not including the crossover)

Thank you. You are helping me get closer to my track layout. Keep coming up with ideas. You are being very helpful.

Another forum suggested that I use Atlas Super Flex Track. What do you think?

flextrack is nice, especially since you can custom-fit the trackage to your space. however, since you are using standard-sized* radii for the curves, sectional track would work just as well. It really comes down to how much room you have after making the curves and adding the crossover. Flextrack might actually be a little easier to get to fit into that space, although you run the risk of over-bending it and/or kinking the joints of you aren’t careful.

  • I’m defining “standard-sized” as anything that you can pick up as sectional track.

You are right, I am probably better off sticking with unitrack.

Can you answer this question?

Can you send me the Kato number for the crossing that connects the figure 8, ie; 20-100 or send me a picture of what it looks like it in the package. This way I will be sure to get the right one.

Thank you

I actually do not know that. I believe that it is either the 60º or the 45º crossing, though it may be the 90º one.

if you go to www.sillub.com and download XtrkCad, you can build the entire layout, and figure out the exact part numbers and number of track sections you will need.

Okay, I have got a little bit closer.

If Kato says that 20-170 will make a circle using 8 tracks, what is the actual width of this circle?

20-170: 216mm (8 9/16 Inch): Radius 45º Curve

I am terrible in math.

The diameter of a circle is twice the radius. Twice 216mm (8 9/16") is 424mm or 17 1/8". Pretty tight radius even for N, will not take bigger locos and longer cars.

Fred W

That’s Okay. I want to run my DisneyWorld train on this track. My husband bought it for me over 20 years ago. It is in N scale and looks exactly like the one in DisneyWorld. It has a coal tender and one passenger car. If you would like I could send you a picture of it using Photobucket. It really is cute. This train is slightly larger than most N scale trains. I can take a picture of it next to my new steam locomotive and you can see the size difference.

Hi,

Take a look at:
http://www.katousa.com/track-plans/n-plans.html

In particular the Tabletop Shortline - this is 20" x 36", and could of course be made a little longer.
The pdf file includes track part numbers.

Alex.