Kato Class 800 Question

[RBTKraisee]

A question for anyone who has a Kato Class 800/Azuma in their collection and who has some sections of track that are approximately R3 11.75"/298mm radius - I'd really like to know how much clearance you need on the outside of that, if you had a second Class 800 coming the other way?

Kato track has 33mm clearance between track centrelines, and I assume that works perfectly. But I do wonder just how close do the trains actually get on 282/315mm track?

Thanks in advance, for any insights!

Ross.

[ntpntpntp]

It just so happens I have an 800 set recently arrived (second hand but only used twice so mint and   half the price of brand new )  and some unused Peco curves in my spares box...

Here's Peco R3 (298mm) and R4 (333mm) giving Setrack 35mm track spacing.  There's about 8 - 9mm clearance



If I keep R3 but reduce the spacing to Streamline 26mm on the outside, I think it's too close for comfort 



I thought I had some Unitrack 282mm curves but it seems not - everything I can find is 315mm.  Given it's only 2mm difference in spacing compared to Peco Setrack I'd expect the clearance to be around 7 - 8mm.

This is all very well but aren't you considering running Shinkansen too?  Some of those have very pronounced "duck bills" so I'd suggest you stick to Setrack spacing for curves of this sort of radius.

[RBTKraisee]

That is absolutely brilliant info, and the pictures REALLY help.

Thank you so much!

Ross.

[Kaput]

Alas I can't test now (lack of board to run a double oval on for one) but before my bout of insanity where I sold up the collection I could easily run an 800 and a Revolution Pendolino on Kato 315/282 ovals with no clearance issues.

[njee20]

Have to agree with Nick - whilst the 800s are long I'd have thought something like a Series 700 Shinkansen will be at least as much of a problem.

[RBTKraisee]

According to Wiki, the Class 800 coaches are 26m long and the 700 Series Shinkansen's are 25m, so I think the Azuma is still the more difficult of tests right now.

Mind you, I personally think that the newer Shinkansen's with the "duckbill" / "shoe" look, are really ugly, so I don't want any of them.

The 500 Series remains one of the prettiest and fastest looking trains of all time. The original 0 Series Bullet Train is iconic, and maybe the 100 Series is too, so I'm planning to have at least one of each of those.

The 800 Series, E7/W7 have all thankfully abandoned the awful duckbill look. Unfortunately, to me, they all just look rather blah compared to the 500.

But the 300 Series, all of the different 700 variants and the E1 thru E5 are all thoroughly fugly.


But, the bottom line is that for my hidden sections where I'm running R3 and R4 track, everything should work without real problems.   I'm planning to use nothing less than 16" radius for my inside tracks on my scenic sections, and by extrapolating from the images above, I'm totally confident I can easily use 1.25" (31.75mm) spacing in my scenic areas and maybe I could go down to as little as 1.00" (25.4mm) - but I'll probably have to get my own Azuma to test each section specifically.

Ross.

[ntpntpntp]

@RBTKraisee   remember it's not just the coach length that is the major factor though this is significant with regard to the overhang on the inside of the curve.  It's also the amount of overhang on the outside of the curve at the ends (that's where the "duckbill" shinkansen would concern me). It depends on the how far the bogies are set in from the ends.

I agree I don't like the look of some of the extreme streamlining on the shinkansen.

[ntpntpntp]

Found this video of a 700 and 923 passing on Kato double track (33mm spacing I presume)

[njee20]

Yes, that was my point - the overhang on the 700 (one of the 'duckbill' models) will be at least as much of a problem. If you plan on anything like an APT-E they have huge overhangs too.

Given you have aspirations toward good looking track, having 32mm spacing will totally undermine that IMO. Bear in mind Peco streamline is 26mm, and prototypical is more like 22mm.

[RBTKraisee]

Oh yes, APT-E is a total nightmare in terms of overhang. It was a pretty bizarre design to begin with! Thankfully, I'm not really interested in it, so I don't need to plan things around that particular headache. APT-P is certainly on my list, but it doesn't have the same problem

As for track spacing, you're right. I want good looking track, but there's no point in doing anything that's going to cause collisions. For straight and nearly-straight sections (say 36" radius and higher), then near-prototypical track spacing should be viable. For hidden sections the R3/R4 spacing will work, as demonstrated above. That leaves the concern focussed to scenic sections with what I consider to be more "medium" radius sections.

I guess that to be 100% confident doing my layout designs, I need to wait until I can get an Azuma/800 myself and test lots of different configurations. With enough data-points I can make a spreadsheet and spit out an equation that can be used in any of my design situations.

Ross.

[njee20]

Remember when I said that you risk turning modelling into a desktop exercise...? Yeah. That.

Why is creating a spreadsheet using the Azuma going to give you 100% confidence? Purely because it's the longest vehicle? What if it's not the one that causes the most problems? Are you going to create a spreadsheet of the bogie overhangs on all 96 of your trains? What about width, relevant for platforms, as well as overhang, particularly if they're curved.

By all means use something to measure, but why create lots of datapoints in a spreadsheet and generate an algorithm? Why not just measure on some paper like Nick has and use that. With 32mm spacing you'll fit anything anyway, he's said as much as shown that very nicely. Job done! Having the lines constantly moving relative to each other will look odd I'd say, particularly if they very evidently open up for curves.

I fear you continue to set yourself for disappointment when you actually build something.

[RBTKraisee]

There's no point in deriving values for all the trains, I'd hope nobody would do that. But getting values for the obvious "worst offenders", that makes sense. Aside from the APT-E and Duckbill Shinkansens (that I don't want anyway) the Azuma/800 looks likely to hold the overhang title right now, so that's my current yardstick - until I can identify a bigger offender!

For my way of working, I find equations to be very useful and easy to use. If I'm designing a section of my layout I might try half a dozen different radius curves to see which works best (and "best" can be a constantly moving target with multiple variables, not least of which is avoiding collisions; train<>train and train<>scenery).

I find it really easy to have a spreadsheet where I can lookup a value quickly for common things, in this case say, needed clearances for 21", 23" or 25" radius inner tracks.

If I can go one step further and quickly turn that into an equation then I can quickly derive useful results, even for unusual start values, say 21.75".

I could draw out every conceivable configuration of track distance in 1/4" increments between 13" (R4) through to 36", which is 92 increments, but that's going to take a long time and waste a lot of paper!

So instead I'd prefer to use the leading "worst case" coach, carefully take a dozen measurements at 2" increments (last one is just 1" different) and that should give me a pretty good curve to work with. I'd add a bit of margin on top of the measured figures, of course.

Then it's a simple matter to derive a full list of all 92 of the 1/4" increments, and also create a cell that allows me to type ANY figure, say 25.625", and it will spit out a minimum safe track spacing number.

It might even take less time to do all that, than to write this explanation! LOL


As for track spacing changing - yes, that's a consideration I'm looking at in my layout plans. It's clear that you can get away with small adjustments and they won't be noticeable, but until I can gather enough information, I can't tell how big the issue actually is in practice.

The info above confirms I'm going to be safe to use R3 and R4 in my hidden sections - which was a major question for me! That's thankfully answered now and I'm very grateful for that info. But what spacing will work best on my scenic sections, currently remains a separate, and open, topic.

Ross.

[njee20]

But that won't account for transition curves or anything. You don't go from a straight to a 14" curve. So you're driven by the lowest common denominator, whatever the tightest is in your scenic section is. Honestly, I'd avoid constantly wandering spacing, it'll just look like badly laid track. You're not going to have a different separation on a 21.675" curve versus a 19.82747483" curve, so it's a bit moot to be able to specify any custom value.

If you want total compatibility then why not just use 32mm everywhere? Are you having two 800s? Because what you really need, for the absolute 'worst' combination is the longest vehicle for the outside track, and whatever has the largest bogie overhang for the inner track. You'll get away with 22mm spacing if the 800 is only ever going to pass a Pannier tank!

I've a vague feeling a Pendolino is worse than an 800 for bogie centre - front distance. There will almost certainly be worst culprits than your 800 among your extensive wish list.

[PaulCheffus]

I've a vague feeling a Pendolino is worse than an 800 for bogie centre - front distance. There will almost certainly be worst culprits than your 800 among your extensive wish list.

Hi

I have both and the Pendolino requires more clearance than the 800 for the front overhang.

Cheers

Paul

[cornish yorkie]

 
  Hi Ross, I have found no problems when running the 800 with the Pendolino or any other Shinkansens. I use Kato track minimum radius of 315mm & track spacing of 33mm.
    stay safe regards Derek