Smallest N guage figure 8

[Pelham Manor Ca]

What is the smallest N guage figure 8 I can make using Kato unitrack?
What size curve tracks will I need?
How many will I need?

What size straight tracks will I need?
How many will I need?

What else will I need?

Thank you.

 

[umtrr-author]

I can't answer this question directly since I am not familiar enough with their product configurations, but does the Kato website offer any information on this?

http://www.katousa.com

A key question would be, assuming that you want a crossing at grade, what crossings are available. That would drive the radius of track and the amount of space needed; generally speaking, the fewer degrees of the crossing, the more length you need (and perhaps less width). A 90 degree crossing would lead to the shortest length.

You would have more flexibility with an up and over figure eight.

 

[60103]

If you turn the crossing the other way, a 30 degree crossing could replace one curve track (if curves are 12 to a circle) in each loop. If the crossing comes out exactly the length of a curve, you get a very tight figure 8.
I suspect a 15 degree crossing would be too long to replace a half-curve, and you would need compensating fractional track on the other side.

 

[Papa Bear]

Kato's website has trackplans on it. They have a figure-8 that uses 9 3/4" Unitrack and fits diagonally on a 42" x 42" table. You could probably get it on a 24" x 60" layout.

They make a 90 degree crossing and a 15 degree crossing. Like David said, the 15 degree crossing is pretty long, about 7 3/4".

 

[Pelham Manor Ca]

Based on your answers, it seems like the figure 8 is too large for the area I will be putting it in. I guess that I will have to go with the smallest oval. Thanks for all your help.

 

[fsm1000]

Smallest n scale I seen was on a cd. So a figure 8 could be the size of two cds.
However for all practical purposes and to run decent sized locos etc. An 18 inch diameter circle twice would be at least 20 by 40 with clearance for overhang etc.
Just my thoughts on the subject.

 

[LoudMusic]

Well, there's also the option of making one side of the 8 inside the other. The overall dimensions of the larger circle would be ... larger, but the overall table size would be smaller. Perhaps 20 x 20 instead of 42 x 42.

 

[Pelham Manor Ca]

Do you mean a circle within a circle?

Some added information that I sent to another forum.
I am including my questions and their answers. Maybe you can help answer my unanswered questions.

Questions
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.

Answer From Forum
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.

Question
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?

Answer
yes, I mean the full section tracks, not the 1/3 section tracks.
The diameter of the circle would have to be 18" in order for the circle to be at least 20" wide. This will decide exactly how many tracks you will need to make the circle part of the figure 8.

Question
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

 

[LoudMusic]

Do you mean a circle within a circle?

Yep! I haven't found an example on the forum (though I have seen them on here) so I made one. Unfortunately that will actually take more than 20" of width. I'd bump it up for 24 x 24 to make it fit comfortably with Kato track. It could be done in less if you used another system or flex track.

 

[Pelham Manor Ca]

My small setup of Kato Unitrack runs 3 trains. I am just adding this figure eight on a space available on my board. So I can use different tracks to make this figure eight.
Thanks for the great idea. I will look into flex track. Maybe that has been my answer all the time instead of trying to use unitrack. Who cares if the tracks are different as long as my trains run on it.

 

[Pelham Manor Ca]

I looked up Atlas Super Flex Track. Now I have to find out if I have to add bedding to the tracks, how they connect and how I add a crossing track that is compatible with flex track. I sent them an email.