unitrack turnout\curve question

[nik_n_dad]

I believe that if you are using #6 kato turnouts, you want to use the 718mm curves (to bring the diverging route back to being parallel).  Would one ever use the 481mm curves with #6's?  When I look at the drawings that show unitrack being used with kato island platforms, they all show the 481mm curves.  so which one (and why or why not)?

 

Thanks

[Mudkip Orange]

Alright, here's all you need to know.

 

The standard Kato track spacing is 33mm.

 

An S-curve of 718mm gets you ONE AND A HALF times the standard spacing (49.5mm)

 

An S-curve of 481mm gets you EXACTLY the standard spacing (33mm)

 

The 64mm straight (on English sites it's the 2 1/2" piece instead of the 2 7/16" piece), when rotated at an angle of 15 degrees, gets you HALF the standard spacing (16.5mm).

 

 

 

Suppose you have a doubletrack main line, and you need to move one out to make room for a platform. Then you'd use a 481mm S-curve to do it.

 

Now suppose you have a single-track main line and you want to use a switch; you could use either the #6 turnout, 718mm curve, and a single 64mm piece, or you could use the #4 turnout and 481mm curve with two 64mm pieces.

 

Now suppose you want to use the #6 turnout to go from single track to double track; this is where you might use both. You'd use a #6 + 64mm + 718mm to get the track double the standard spacing away, and then you'd use a couple of 481mm to bring it back in one standard spacing, so that you have standard-spaced tracks.

 

 

 

Did this help or am I completely misunderstanding your question

[Nozomi]

An S-curve of 718mm gets you ONE AND A HALF times the standard spacing (49.5mm)

 

Is this right thing to do if I want to use Kato's ISLAND Platform sets?

[inobu]

There are differences in platform ends. For example: The 23-103 #2 platform end has a 718-15 arc where as the 23-105 #4 platform end has R481-15 arc.

 

 

 

 

Note: that these arcs are also associated with the turnouts EP481-15 R/L or EP718-15 R/L normally referred to #4 and #6 turn outs.

 

So you must take into consideration which platform ends are being incorporated into the layout design. The platform ends should fit exactly between the turnout and will derive the correct station track length as well as the standard 33mm, 66mm and 99mm  track width as Mudkip referred to earlier.

 

If you maintain the correct track length values into the station from a #4 or #6 turn out the 481 and 718 curves will transition into the station smoothly allowing the platforms to align with either a S124 or S248 track extension. When you deviate from those values it throws the width values out, causing misalignment between the track and platforms.   

 

Inobu

 

[nik_n_dad]

ah! this is the key.  I didn't have the measurements for the various platforms and so it wasn't clear.

 

So is there any issue with using the 481's with #6's?  Will it be too much of a transition?

 

Another place I'm looking at looking at the 481's & or 718's would be in a yard.  In this case, I want to compress as much track as possible into as small of a space as I can.

[bill937ca]

This may help.

 

Track geometry.

 

http://www.kato-unitrack.com/kato/en/gleisgeometrie/Geometrie_der_Weichen.php

 

Another set of diagrams with separate configurations for #4 and #6 switches.

 

http://www.nscalesupply.com/KAT/KAT-Unitrack.html

 

Track plans

 

http://www.kato-unitrack.com/kato/en/technik_und_gleisplaene/fertige_gleisplaene/index.php

 

This track plan has a couple of stations and you can check out individual track pieces on the plans.

 

http://www.kato-unitrack.com/kato/en/gleisgeometrie/Geometrie_der_Weichen.php

 

Your switch and curve configuration will be the same whether you run 2 car trains or 16 car trains.  The configuration is determined by the width of the platform you are making space for.

 

http://www.kato-unitrack.com/kato/pictures/shop/Gleisplan9.jpg

[Mudkip Orange]

So is there any issue with using the 481's with #6's?  Will it be too much of a transition?

 

The issue is, you will be unable to attain the standard Kato track spacing.

 

For instance, recall that a 718mm S-curve is one-and-a-half times the standard spacing, or 49.5mm. That means a single 718mm curve (or a #6 - they're the same) will move you out 3/4s of the standard spacing. If you then put a 481mm curve on the other end, it will add another 1/2 of the spacing, so you'll have 1 and 1/4 times the standard spacing, or 41.25mm. If you add a 64mm straight in between you'll have 57.75mm, and if you add another 64mm straight you'll have 74.25mm.

 

You can't put an island platform between tracks on 57.25mm spacing without "forcing" the tracks open a few mm, and even then your trains will probably run the platform.

 

And if you put an island platform between tracks on a 74.25mm spacing, there will be an unrealistic gap between the cars and the platform edge.

 

 

 

In short, just friggin use the 481s with the #4s and the 718s with the #6s and everything will be fine.

[nik_n_dad]

That's the answer I was looking for!

[scott]

OK--since RailModeller is driving me crazy--do you use a 64mm straight or a 124mm straight between a #6 turnout and 781 curve to put tracks on both sides of an island platform?

[qwertyaardvark]

OK--since RailModeller is driving me crazy--do you use a 64mm straight or a 124mm straight between a #6 turnout and 781 curve to put tracks on both sides of an island platform?

 

64mm straight. For the kato island platforms, you are wanting 66mm between the two tracks. :)

 

http://www.katousa.com/cgi-bin/dl/dl.pl?dl.mif,N-plan-6-turnouts.pdf

[Mudkip Orange]

You use a short fitter piece of Atlas SNAP TRACK, which you cut yourself using an Atlas SNAP SAW.

[quinntopia]

This was a great thread!  I've only worked through these questions through trial and error, now I can actually plan it correctly!

[scott]

 

64mm straight. For the kato island platforms, you are wanting 66mm between the two tracks. :)

 

http://www.katousa.com/cgi-bin/dl/dl.pl?dl.mif,N-plan-6-turnouts.pdf

 

 

Great--thanks!