# A geometry problem



## GNfan (Jun 3, 2016)

Before I buy an MRC power pack I want to "price out" what this 2'x2' layout would cost with 2 turnouts and Kato electrical components including a Kato power pack. My understanding is that any variable DC power pack can power the rails; but only a Kato power pack provides the DC necessary to power Kato turnouts without "getting creative" (like finding a DC wall-wart of appropriate voltage).








A and C are half-circles of 9¾ inch radius Kato Unitrack. If the turnouts are Unitrack #4's, how do I figure out what pieces of Unitrack go together to make B? Or do I have to buy all the parts and an assortment of "fitters" and find the answer by trial-and-error? The turnouts are ~$30 each at modeltrainstuff.com.


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## DonR (Oct 18, 2012)

The normal MRC 'power pack' provides DC power for the tracks
and AC power for turnouts and accessories. The Kato turnouts
require DC power for their single coil motors. You can use
an old DC power pack 'track' terminals...or old unused 
'Wall Warts' that have a DC output of 12 to 14 volts or so. Either
would be all you need for the Katos.

Someone with Kato experience may help you with estimating
the cost of the tracks you'll need.

Don


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## OilValleyRy (Oct 3, 2021)

Ugg, math. And I think this is one of those instances where some lunatic decide what math really needed was the alphabet.

Unless I’m mistaken, the curves you’re planning to use on the outer curves are 15 degrees each, 9 & 3/4 radius. If you use a different size, you’ll have a different number of sections, which is fine, but I’m getting to the middle.

To get a circle you need 360 degrees.
The two turnouts are 15 degrees each.
Curve A is 180 degrees regardless of how many pieces it is, but lets say 4.

4x45 = 180.
180+15+15=210.
360-210=120.

So curve B, NOT counting the turnouts, needs to total 120 degrees. Whether it is 3 pieces, 4 pieces, or 6…. The degrees need to total 120 for that section. 120 / 8 = 15. So I think 8 of those shorter 15 degree curves would work. Luckily they’re sold in packs of 4.
BUT, I’m not sure of the radius of those short curve pieces. Just because the degrees add up doesn’t mean the radius will. I _think_ they’re 19” but not positive. So hopefully someone with 8 of those pieces laying around can fit them together and see if the diameter of the curve is close to 19”. If they have 1 or 2 #4s they could verify it entirely.


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## CTValleyRR (Jul 26, 2014)

Look at the Kato starter sets. I'm pretty sure one of them is an oval track in that same general configuration. You would just leave out the straight segments from the top and bottom legs. It may be cheaper than purchasing individual section packs.


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## Steve Rothstein (Jan 1, 2021)

The problem you will have is that the #4 turnout uses a 15 degree section of 19 inch (481 mm) radius The only way I can see to make it work with the outer circle being 9.75 inch radius is to use a piece of flex track. It wont give you a perfectly smooth inner curve like the outer two, but you should be able to make it fit.


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## Mixed Freight (Aug 31, 2019)

Okay, for your track problem, here's a couple of solutions........................
For curves "A" and "C", you need 8 = 9-3/4" radius x 45° sections (4 pieces for each curve).

For curve "B", you need 2 = 9-3/4" radius x 45°, and 4 = 9-3/4" radius x 15°.
Starting at one #4 turnout, place them thus: 45, 15, 15, 15, 15, and 45.

Now, you're going to have a slight problem. Halfway through curves A and C, you're going to have approx. a 5/8" gap. Kato does not make a fitter piece this short. You can cut two fitter pieces x 5/8" long from Atlas code 80 track, and fill in the gap on each curve.

Or, you can purchase a few additional Kato fitter pieces, and use them as thus: you need 1 = 1.14" (S29) straight track, and place it in the center of curve "B". You will also need 2 = 1.79" (S46) straight tracks, and place them in the centers of curves "A" and "C". That will take care of the gaps.

Hope this helps.


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## Spruslayer (Dec 13, 2020)

file:///C:/Users/miket/AppData/Local/Temp/SCARM/PL/list.html
Hope this helps
The SCRM link has a parts list
For what its worth, i have had two #4 kato turnout's out of the six i used fail in less than a year but that could just be my luck,your mileage may vary.
Another option could be to use Kato flex track for the curve B


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## Mixed Freight (Aug 31, 2019)

Spruslayer said:


> View attachment 570237
> 
> SCARM - Parts List
> Hope this helps
> The SCRM link has a parts list


Your SCARM - Parts List link isn't working. At least not for me.
Can't quite make out your track pieces either, on your provided drawing.


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## Spruslayer (Dec 13, 2020)

nts: *All parts in the project*


No.ImageNumberNameScaleProducerPcs.Note1





20‑100R249‑45NKato10 2





20‑101R249‑15NKato2 3





20‑171R216‑15NKato2 4





20‑220EP481‑15LNKato1 5





20‑221EP481‑15RNKato1 *Total:*​*16*_Tracks count: 16_
_Generated by SCARM 1.9.0_ - www.scarm.info

My link foo is lacking this moning


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## Mixed Freight (Aug 31, 2019)

Spruslayer said:


> nts: *All parts in the project*
> 
> 
> No.ImageNumberNameScaleProducerPcs.Note1
> ...


Ahhh, okay. I see you used a couple of R216-15 pieces. I used ALL R249-XX (9-3/4" Radius) pieces, so as to not compromise the already bare minimum radius (IMHO) that GNfan was more or less planning on.


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## T-Man (May 16, 2008)

There is a different approach. This link has multiple small track plans. Determine your final size. Then build part of it as your budget allows. Eventually you will complete the layout. All the pieces are listed. This is just one site I found. There are many more. Search Kato track plans then filtered for N scale.

OK just look at his one. Loop de Loop. The above page shows some measurements for standard track features. This link uses the Number 4 curve.


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## OilValleyRy (Oct 3, 2021)

Actually it’s possible to make custom length pieces using Kato track.
Measure out & mark the 1/2 the length you need from each end on the underside. Cut through the ballast. Remove 1 rail joiner. Slip off both, now loose pieces. Discard the middle, replace the end portion of ballast. Trim rail to length, re-insert joiner.


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## Mixed Freight (Aug 31, 2019)

Steve Rothstein said:


> The problem you will have is that the #4 turnout uses a 15 degree section of 19 inch (481 mm) radius The only way I can see to make it work with the outer circle being 9.75 inch radius is to use a piece of flex track. It wont give you a perfectly smooth inner curve like the outer two, but you should be able to make it fit.


Good point. I don't have any Kato track, but if the #4 turnouts are as you say (a 15 degree section of 19" radius track), then there is another approach that GNfan could do while still maintaining his basic oval.............................

Attach two 19" radius (481 mm) x 15° curve sections to the right hand curve of the turnout. Attach two more to the left hand curve of that turnout. Then fill in between with two 9-3/4" radius (249 mm) x 45° curve sections. This effectively makes up curve "B".

For curve "A", start with three 19" radius x 15° curve sections, then two 9-3/4" x 45° curve sections, then finish with 3 more 19" radius x 15° curve sections. Next, do the exact same thing all over again for curve "C".

Abbreviated parts list:

2 = #4 Turnouts (one LH & one RH).
16 = 19" (481 mm) radius x 15° curved sections.
6 = 9.75" radius (249 mm) x 45° curved sections.
One cool thing happens with this setup - Easements! But your 2' x 2' layout area will need to increase a little in length. Maybe more like 2.25' ~ 2.5' long or thereabouts.


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## GNfan (Jun 3, 2016)

*Wow. Thank you, everyone. *I didn't realize how complicated this would be. Spruslayer's answer was the kind I was looking for; that there was some mixture of off-the-shelf Unitrack curved pieces that would fit within a millimeter or so. When I started this my objective was what N-scaler's call a "pizza box layout" - usually an "over and under loop-de-loop" made from one or two sections of flextrack and a bridge and pier set. I started playing with Unitrack dimensions, noticed a couple of useful coincidences; and put together two loops that were electrically separate but physically connected using double track sections. I've put together two nice trains of small locomotives and 40-foot reefers. And together with the other research I've already done into prices; *I've come to the conclusion that the added operating interest the two turnouts and siding provide isn't worth the additional expense. *So I'm going to finish wiring the two nested loops I've got. Besides, I hear some of my favorite structures calling, and that's the next phase. *Thank you again.*


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## Aqualungs (Jan 25, 2021)

You can get one of these to power you DC Kato turnouts. You connect the leads to your AC controller.









Kato HO/N 24842 Unitrack DC Convertor


Kato HO/N 24842 Unitrack DC Convertor




www.modeltrainstuff.com





Sent from my SM-G998U using Tapatalk


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## GNfan (Jun 3, 2016)

Aqualungs said:


> You can get one of these to power you DC Kato turnouts. You connect the leads to your AC controller.


I hadn't seen that before. There doesn't seem to be much rhyme or reason to how the Kato is organized at modeltainstuff.com. Thank You.


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## Aqualungs (Jan 25, 2021)

GNfan said:


> I hadn't seen that before. There doesn't seem to be much rhyme or reason to how the Kato is organized at modeltainstuff.com. Thank You.


For sure! I needed to take the jumper pack from my existing railroad and use it for the train under the tree. I can use wifi controllers so no biggie, but had no way to power my kato turnouts. I found this looking for another jumper 

Sent from my SM-G998U using Tapatalk


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