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Online Harvey  
#1 Posted : 19 July 2018 17:58:29(UTC)
Harvey

United States   
Joined: 17/02/2008(UTC)
Posts: 591
Location: Glen Oaks, N.Y.
The current issue of Marklin Magazine (June/July 2018) mentions on page 48 'A cant given to the outer rails on curves offers a more realistic appearance and improves operational safety when you get to grips with such kinks.

The explanation is very brief and unclear - obviously this the article assumes greater knowledge by the reader, which I don't have. Does anyone have a link to an instructional video? Or explanation?

Regards
Harvey
Offline DaleSchultz  
#2 Posted : 19 July 2018 18:30:47(UTC)
DaleSchultz

United States   
Joined: 10/02/2006(UTC)
Posts: 3,997
a cant is a small tilt.

they are talking about superelevation - the outer rail is lifted slightly to tilt the train inwards on curves.
Dale
Intellibox + own software, K-Track
My current layout: https://cabin-layout.mixmox.com
Arrival and Departure signs: https://remotesign.mixmox.com
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Offline Webmaster  
#3 Posted : 19 July 2018 19:11:22(UTC)
Webmaster


Joined: 25/07/2001(UTC)
Posts: 11,161
Juhan - "Webmaster", at your service...
He who asks a question is a fool for five minutes. He who does not ask a question remains a fool forever. [Old Chinese Proverb]
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Offline GlennM  
#4 Posted : 19 July 2018 19:28:59(UTC)
GlennM

United Kingdom   
Joined: 09/05/2011(UTC)
Posts: 2,877
Location: Somewhere, But Nowhere Near Manchester, England
As has been mentioned by Dale in this instance the cant is making the outer edge of the track elevated so the track slopes into the curve allowing the train to run faster into the curve.

These may help;

camber.jpg

Nem 114.jpg

Curve.jpg

And an image showing one way of achieving this with K-track

Track Cant.jpg


BR
Don't look back, your not heading that way.
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Offline DaleSchultz  
#5 Posted : 19 July 2018 20:18:48(UTC)
DaleSchultz

United States   
Joined: 10/02/2006(UTC)
Posts: 3,997
BTW, I find 1mm superelevation is not enough. I went for 2mm. (HO)
Dale
Intellibox + own software, K-Track
My current layout: https://cabin-layout.mixmox.com
Arrival and Departure signs: https://remotesign.mixmox.com
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Offline Minok  
#6 Posted : 19 July 2018 22:43:20(UTC)
Minok

United States   
Joined: 15/10/2006(UTC)
Posts: 2,310
Location: Washington, Pacific Northwest
Yes, super-elevation is the term in English. Same term used for roadways built by highway departments. Same purpose they exist there - to help with redirecting the forces in a curve, so the vehicle can make the curve at speed easier. A more prototypical construction for models.
Toys of tin and wood rule!
---
My Layout Thread on marklin-users.net: InterCity 1-3-4
My YouTube Channel:
https://youtube.com/@intercity134
Offline kimballthurlow  
#7 Posted : 19 July 2018 22:53:04(UTC)
kimballthurlow

Australia   
Joined: 18/03/2007(UTC)
Posts: 6,653
Location: Brisbane, Australia
Originally Posted by: DaleSchultz Go to Quoted Post
BTW, I find 1mm superelevation is not enough. I went for 2mm. (HO)


In fact the cant (or super-elevation) on a real railroad is in the order of 6 inches = approx 2mm in HO.
That can vary depending on radius of the curve, and likely speed of the trains.
If you can achieve it, the models look more realistic when running.

My layout is notable for its absence, and in two months I have an open day at my layout (for the NMRA).
If I have time, I intend to super-elevate my visible curves by inserting strips of cardboard under the outer edges of the C track.

It is a shame that Maerklin do not simply modify the plastic base for C track to include this superelevation, but perhaps that might cause problems in simple home set ups.
VB track (similar to M track) made in France in the 1950s included the cant in their curved track, it seems without problems.

Kimball
HO Scale - Märklin (ep II-III and VI, C Track, digital) - 2 rail HO (Queensland Australia, UK, USA) - 3 rail OO (English Hornby Dublo) - old clockwork O gauge - Live Steam 90mm (3.1/2 inch) gauge.
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Offline xxup  
#8 Posted : 20 July 2018 05:32:43(UTC)
xxup

Australia   
Joined: 15/03/2003(UTC)
Posts: 9,457
Location: Australia
In Australia, the slope of a road from the center line is called Camber.. it's main purpose is for water drainage. On a two-way highway, the road's camber will start from the outer edge on a high-speed curve - Australian Engineers call this the bank angle of a curve or sometimes a banked turn - it stops Volvos from sliding off the road when it rains.. RollEyes

I am pretty sure that super-elevation is an American term..Cool
Adrian
UserPostedImage
Australia flag by abFlags.com
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Offline PJMärklin  
#9 Posted : 20 July 2018 08:54:33(UTC)
PJMärklin

Australia   
Joined: 04/12/2013(UTC)
Posts: 2,206
Location: Hobart, Australia
Originally Posted by: xxup Go to Quoted Post
- it stops Volvos from sliding off the road when it rains.. RollEyes

Please cease right there!!! Flapper
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Offline GlennM  
#10 Posted : 20 July 2018 13:15:39(UTC)
GlennM

United Kingdom   
Joined: 09/05/2011(UTC)
Posts: 2,877
Location: Somewhere, But Nowhere Near Manchester, England
Originally Posted by: xxup Go to Quoted Post
In Australia, the slope of a road from the center line is called Camber.. it's main purpose is for water drainage. On a two-way highway, the road's camber will start from the outer edge on a high-speed curve - Australian Engineers call this the bank angle of a curve or sometimes a banked turn - it stops Volvos from sliding off the road when it rains.. RollEyes

I am pretty sure that super-elevation is an American term..Cool


IMHO based on my construction experience;

In UK road construction the camber is the curvature of the road surface itself, the primary reason for camber is to allow for drainage of water from the surface. The highest point of the camber is known as the crown.

Whereas superelevation is the vertical distance between the height of inner and outer edges of the road surface (or inner and outer rails of rail track). The primary reason for superelevation it is to counter act centrifugal forces acting upon vehicle. Superelevation is often more commonly know as 'banking'.

The combination of superelevation and camber will be down to calculations undertaken to determine likely rain fall. The movement of excess amounts of water across a superelevated surface can lead to vehicles aquaplaning.

I am unaware of the origin of the term superelevation but I can assure you that it has been in common use in UK construction for at least 100 years

It is therefore correct that superelevation is there to stop Volvos (and other vehicles) from sliding off and loosing control, but in reality it is camber than possibly leads to more actual accidents, in particular in roadworks, which is one reason in roadworks when changing road surfaces or changing from one carriageway to another, the speed is reduced, because sudden camber changes, or adverse cambers, or reverse cambers can cause loss of control at speed, and if you add inclement weather into the equation the likelihood is even higher.

Drive safely

BR
Don't look back, your not heading that way.
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Offline DV  
#11 Posted : 20 July 2018 15:01:00(UTC)
DV

Australia   
Joined: 29/11/2009(UTC)
Posts: 954
Location: Mount Barker, South Australia
Originally Posted by: GlennM Go to Quoted Post
Originally Posted by: xxup Go to Quoted Post
In Australia, the slope of a road from the center line is called Camber.. it's main purpose is for water drainage. On a two-way highway, the road's camber will start from the outer edge on a high-speed curve - Australian Engineers call this the bank angle of a curve or sometimes a banked turn - it stops Volvos from sliding off the road when it rains.. RollEyes

I am pretty sure that super-elevation is an American term..Cool


IMHO based on my construction experience;

In UK road construction the camber is the curvature of the road surface itself, the primary reason for camber is to allow for drainage of water from the surface. The highest point of the camber is known as the crown.

Whereas superelevation is the vertical distance between the height of inner and outer edges of the road surface (or inner and outer rails of rail track). The primary reason for superelevation it is to counter act centrifugal forces acting upon vehicle. Superelevation is often more commonly know as 'banking'.

The combination of superelevation and camber will be down to calculations undertaken to determine likely rain fall. The movement of excess amounts of water across a superelevated surface can lead to vehicles aquaplaning.

I am unaware of the origin of the term superelevation but I can assure you that it has been in common use in UK construction for at least 100 years

It is therefore correct that superelevation is there to stop Volvos (and other vehicles) from sliding off and loosing control, but in reality it is camber than possibly leads to more actual accidents, in particular in roadworks, which is one reason in roadworks when changing road surfaces or changing from one carriageway to another, the speed is reduced, because sudden camber changes, or adverse cambers, or reverse cambers can cause loss of control at speed, and if you add inclement weather into the equation the likelihood is even higher.

Drive safelyThumpUp

BR


Having been a road designer (including freeways) for 47 years (not a ginger beer - engineer BigGrin BigGrin BigGrin, just a lowly techo Crying Crying ), Glenn is 100% correct.

Super elevation is the correct term used by English speaking countries for elevating roads/rail so that vehicles can travel at safe speeds through curves.

If you suffer from insomnia, I am quite happy to explain how that is achieved, including the maths behind itLOL LOL LOL

And yes, I have used 'super' on all my layouts ( I even had a boss who actually designed the 'super' for his layout), not by calculations, but by - if it looks good, it must be goodThumpUp ThumpUp ThumpUp, in other words trail and errorSmile Smile Smile
Dusan V
'I find your lack of faith (in Märklin) disturbing'
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Offline utkan  
#12 Posted : 20 July 2018 15:01:48(UTC)
utkan

Turkey   
Joined: 14/07/2009(UTC)
Posts: 19,116
Location: Istanbul,
For me a cant is can't...you see at the times I was building my humble layout I was not aware of this...so I couldn't....Crying

..and now it is a heart-ache....Crying Crying
Do unto others, as you would have them do unto you...
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Offline midwestbls  
#13 Posted : 20 July 2018 16:34:53(UTC)
midwestbls

United States   
Joined: 04/06/2012(UTC)
Posts: 76
To (mis)quote the Marshall Tucker Band: "Can't you see? Can't you see? What this [hobby's] been doin' to me."
ETE - Swiss Era III - BLS - Brig Station
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Offline David Dewar  
#14 Posted : 20 July 2018 16:44:28(UTC)
David Dewar

Scotland   
Joined: 01/02/2004(UTC)
Posts: 7,332
Location: Scotland
Cant on roads does not matter or is not needed if you drive a Subaru. Useful though if you want to drive your trains round sharp corners at their top speed.
Take care I like Marklin and will defend the worlds greatest model rail manufacturer.
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Offline Minok  
#15 Posted : 20 July 2018 17:07:42(UTC)
Minok

United States   
Joined: 15/10/2006(UTC)
Posts: 2,310
Location: Washington, Pacific Northwest
Originally Posted by: David Dewar Go to Quoted Post
Cant on roads does not matter or is not needed if you drive a Subaru. Useful though if you want to drive your trains round sharp corners at their top speed.


I disagree. Both super elevation and surface cant are there to affect tire / wheel adhesion/friction and the forces at play while rolling. Having all wheel drive doesn't make your tires gain friction, they are just as likely to aquaplane or suspetible to centrifugal forces as a 2wd vehicle. Now with an awd vehicle you can accelerate better within the limits of adhesion but under braking or when the traction of all 4 tires vs the friction forces on the road are concerned the awd system provides no benefit.
Toys of tin and wood rule!
---
My Layout Thread on marklin-users.net: InterCity 1-3-4
My YouTube Channel:
https://youtube.com/@intercity134
Offline TEEWolf  
#16 Posted : 20 July 2018 18:55:46(UTC)
TEEWolf


Joined: 01/06/2016(UTC)
Posts: 2,465
Originally Posted by: Harvey Go to Quoted Post
The current issue of Marklin Magazine (June/July 2018) mentions on page 48 'A cant given to the outer rails on curves offers a more realistic appearance and improves operational safety when you get to grips with such kinks.

The explanation is very brief and unclear - obviously this the article assumes greater knowledge by the reader, which I don't have. Does anyone have a link to an instructional video? Or explanation?

Regards
Harvey


Hi Harvey,

in the German Version of the MM 03/2018 page 48 is the first part of the article (great driving experience) about the MS 2.

To which article does your question refer? Is it the one "electronic milestone", the "project digital track" describing the ETCS system? (This is at the German Issue on page 94 et seqq). Or another one? Or does your issue have even articles which are not in the German issue?

Thanks

Regards

Wolfgang
Offline fusionfaded  
#17 Posted : 20 July 2018 18:57:08(UTC)
fusionfaded

Switzerland   
Joined: 04/01/2018(UTC)
Posts: 33
Originally Posted by: kimballthurlow Go to Quoted Post

It is a shame that Maerklin do not simply modify the plastic base for C track to include this superelevation, but perhaps that might cause problems in simple home set ups.
VB track (similar to M track) made in France in the 1950s included the cant in their curved track, it seems without problems.
Kimball


You would end up with a super-elevated piece, two transition pieces in addition to the normal track piece. Lower volume of each part would mean higher prices and a bigger mess for both dealers and users. On the other hand, the cardboard alternative is quite cheap, doesn't need any new items and you use whatever amount of cant you want.
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Offline Webmaster  
#18 Posted : 20 July 2018 21:44:59(UTC)
Webmaster


Joined: 25/07/2001(UTC)
Posts: 11,161
Originally Posted by: David Dewar Go to Quoted Post
Cant on roads does not matter or is not needed if you drive a Subaru. Useful though if you want to drive your trains round sharp corners at their top speed.


On race tracks, it's usually called banked curves... (Using faster cars than Subaru)... BigGrin

Sorry for the OT comment, Friday night... LOL

Juhan - "Webmaster", at your service...
He who asks a question is a fool for five minutes. He who does not ask a question remains a fool forever. [Old Chinese Proverb]
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Offline David Dewar  
#19 Posted : 20 July 2018 21:52:00(UTC)
David Dewar

Scotland   
Joined: 01/02/2004(UTC)
Posts: 7,332
Location: Scotland
Originally Posted by: Minok Go to Quoted Post
Originally Posted by: David Dewar Go to Quoted Post
Cant on roads does not matter or is not needed if you drive a Subaru. Useful though if you want to drive your trains round sharp corners at their top speed.


I disagree. Both super elevation and surface cant are there to affect tire / wheel adhesion/friction and the forces at play while rolling. Having all wheel drive doesn't make your tires gain friction, they are just as likely to aquaplane or suspetible to centrifugal forces as a 2wd vehicle. Now with an awd vehicle you can accelerate better within the limits of adhesion but under braking or when the traction of all 4 tires vs the friction forces on the road are concerned the awd system provides no benefit.


Follow me round a corner in a two wheel or just front wheel drive and you will spin off the road. The only car to match a Subaru is a Range Rover in tests done. Sorry I don't now have the videos. Also on snow again the Ranger Rover did well while a four wheel drive Audi was written off. Subaru engine and drive is somewhat unique. I have had them through rivers (not too deep clearly) and up and down hills using their X Mode which drives the car itself. However they are not for everybody as expensive on fuel and don't have a fancy badge like Mercs etc. Not too sure what all this means for a cant though lol.
Take care I like Marklin and will defend the worlds greatest model rail manufacturer.
Offline mike c  
#20 Posted : 20 July 2018 22:47:42(UTC)
mike c

Canada   
Joined: 28/11/2007(UTC)
Posts: 7,880
Location: Montreal, QC
It might be interesting if Maerklin would come out with new curves, with banking. The first section would start from flat on one end and then have a cant (bank) on the other end. The next section would be a fully banked section and the third would be the inverse of the first. For a complete curve, you would have to use one entry section, four banked sections and then an exit section.
The other possibility would be to have all curve tracks with bank and have straight sections for the entry/exit sections.

They would still have to make non banked curved sections for use with switches and in S-curves.

Any thoughts?

Regards

Mike C
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Offline TEEWolf  
#21 Posted : 20 July 2018 23:17:56(UTC)
TEEWolf


Joined: 01/06/2016(UTC)
Posts: 2,465
Originally Posted by: kimballthurlow Go to Quoted Post
Originally Posted by: DaleSchultz Go to Quoted Post
BTW, I find 1mm superelevation is not enough. I went for 2mm. (HO)


In fact the cant (or super-elevation) on a real railroad is in the order of 6 inches = approx 2mm in HO.
That can vary depending on radius of the curve, and likely speed of the trains.
If you can achieve it, the models look more realistic when running.

My layout is notable for its absence, and in two months I have an open day at my layout (for the NMRA).
If I have time, I intend to super-elevate my visible curves by inserting strips of cardboard under the outer edges of the C track.

It is a shame that Maerklin do not simply modify the plastic base for C track to include this superelevation, but perhaps that might cause problems in simple home set ups.
VB track (similar to M track) made in France in the 1950s included the cant in their curved track, it seems without problems.

Kimball


Why a shame for Märklin? The internet provides you with everything, even with cant roadbeds. Searched for you a little bit and here a few links:

http://kuenstlerstadt.at...eisbogenueberhoehung.php

http://shop.lokliege.de/...leisbettung-h0-r600.html

https://www.merkur-styro...treifen-901010::333.html

http://www.lokliege.de/9.html

and because it is Friday here some theoretical explanations

http://deacademic.com/di...enen%C3%BCberh%C3%B6hung

http://deacademic.com/di...%9Cberh%C3%B6hungsrampen

https://slideplayer.org/slide/214779/

for your weekend relaxation a short video showing these cants in real operation mode.



Enjoy your weekend studying - or not. In Germany is summertime with round about 30° C every day. I cannot afford to study by these temperatures.Laugh

Have a nice weekend.BigGrin

TEEWolf









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Offline DaleSchultz  
#22 Posted : 20 July 2018 23:25:26(UTC)
DaleSchultz

United States   
Joined: 10/02/2006(UTC)
Posts: 3,997
Originally Posted by: mike c Go to Quoted Post
It might be interesting if Maerklin would come out with new curves, with banking. The first section would start from flat on one end and then have a cant (bank) on the other end. The next section would be a fully banked section and the third would be the inverse of the first. For a complete curve, you would have to use one entry section, four banked sections and then an exit section.
The other possibility would be to have all curve tracks with bank and have straight sections for the entry/exit sections.

They would still have to make non banked curved sections for use with switches and in S-curves.

Any thoughts?

Regards

Mike C


I think the much simpler option is to produce elevation pieces that simply clip on the bottom of existing track. This removes the all the complexity of having left curve - descending, left curve - ascending and left curve - high, left curve -none. You just have the curve (= both left and right) and you add the spacers as needed. new product number, something more to sell.

Dale
Intellibox + own software, K-Track
My current layout: https://cabin-layout.mixmox.com
Arrival and Departure signs: https://remotesign.mixmox.com
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Offline TEEWolf  
#23 Posted : 20 July 2018 23:42:43(UTC)
TEEWolf


Joined: 01/06/2016(UTC)
Posts: 2,465
Originally Posted by: DaleSchultz Go to Quoted Post
Originally Posted by: mike c Go to Quoted Post
It might be interesting if Maerklin would come out with new curves, with banking. The first section would start from flat on one end and then have a cant (bank) on the other end. The next section would be a fully banked section and the third would be the inverse of the first. For a complete curve, you would have to use one entry section, four banked sections and then an exit section.
The other possibility would be to have all curve tracks with bank and have straight sections for the entry/exit sections.

They would still have to make non banked curved sections for use with switches and in S-curves.

Any thoughts?

Regards

Mike C


I think the much simpler option is to produce elevation pieces that simply clip on the bottom of existing track. This removes the all the complexity of having left curve - descending, left curve - ascending and left curve - high, left curve -none. You just have the curve (= both left and right) and you add the spacers as needed. new product number, something more to sell.



Sure, all already done. Buy here for 65 cents per 50 cm or 1,30 €/m piece.
Text says:
"Superelevation strips, length 50 cm, track elevations for track bends for a realistic increase in the course of the track."


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Offline kimballthurlow  
#24 Posted : 21 July 2018 01:21:24(UTC)
kimballthurlow

Australia   
Joined: 18/03/2007(UTC)
Posts: 6,653
Location: Brisbane, Australia
Originally Posted by: fusionfaded Go to Quoted Post
Originally Posted by: kimballthurlow Go to Quoted Post

It is a shame that Maerklin do not simply modify the plastic base for C track to include this superelevation, but perhaps that might cause problems in simple home set ups.
VB track (similar to M track) made in France in the 1950s included the cant in their curved track, it seems without problems.
Kimball


You would end up with a super-elevated piece, two transition pieces in addition to the normal track piece. Lower volume of each part would mean higher prices and a bigger mess for both dealers and users. On the other hand, the cardboard alternative is quite cheap, doesn't need any new items and you use whatever amount of cant you want.


Originally Posted by: mike c Go to Quoted Post
It might be interesting if Maerklin would come out with new curves, with banking. The first section would start from flat on one end and then have a cant (bank) on the other end. The next section would be a fully banked section and the third would be the inverse of the first. For a complete curve, you would have to use one entry section, four banked sections and then an exit section.
The other possibility would be to have all curve tracks with bank and have straight sections for the entry/exit sections.

They would still have to make non banked curved sections for use with switches and in S-curves.

Any thoughts?

Regards

Mike C


Actually there is no transition section (increasing height) in the fixed curve itself.
(On a real railroad or road, this would be done in a horozontal and vertical transition section between the straight and the fixed curve, but not really practical for most model sets).

On a model train set with sectioned track (eg. C track) you need a transition of increasing superelevation before the curve.
In effect, an increasing superelevation on the straight (tangent) leading into the curve, practically about 50mm in length.
But there is in my opinion no need to bank that separately.
The reason is we are dealing with very small scale, and the lift given to the outer rail in the first curve section will raise the outer rail of the tangent piece effectively.
For the same reason a simple 2mm height is all that is needed for all curved pieces.
(For Mike C) And for the same reason it would not affect the placement for switches and S bends.

I actually use my cardboard (or foam which is flexible) strips starting a small distance in the tangent, but it is not absolutely necessary.

Adding the elevation to the outer rail in the roadbed was easy for VB (France) because they sold only 2 radii, large and small.
I can see it being difficult for Maerklin, with 6 different radii in C track, in multiple lengths.

Kimball

Edited by user 24 July 2018 04:27:27(UTC)  | Reason: corrected the error about straight transitions

HO Scale - Märklin (ep II-III and VI, C Track, digital) - 2 rail HO (Queensland Australia, UK, USA) - 3 rail OO (English Hornby Dublo) - old clockwork O gauge - Live Steam 90mm (3.1/2 inch) gauge.
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Offline analogmike  
#25 Posted : 21 July 2018 01:59:57(UTC)
analogmike

United States   
Joined: 02/08/2014(UTC)
Posts: 737
Location: NEW JERSEY, USA
Whatever you want to call it, this is what it looks like.

rmc-commuter-layout-01.jpg
I love the smell of smoke fluid in the morning .
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Offline cookee_nz  
#26 Posted : 21 July 2018 05:05:10(UTC)
cookee_nz

New Zealand   
Joined: 31/12/2010(UTC)
Posts: 3,948
Location: Paremata, Wellington
I always thought it was an American version of a UK one?, or perhaps Australian.

A decade or two ago it was popular to be considered a SNAG - a Sensitive New-Age Guy.

Then there was those who considered themselves more the Caring Understanding Nurturing Type.
Cookee
Wellington
NZ image
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Offline Nigel Packer  
#27 Posted : 21 July 2018 09:38:57(UTC)
Nigel Packer

United Kingdom   
Joined: 11/02/2006(UTC)
Posts: 682
Location: Cheshire, UK
As a child, my mother always used to tell me: “There’s no such word as can’t”!

Nigel
Märklin collector since age 5.
H0 Collection from 1935 to today.
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Offline fusionfaded  
#28 Posted : 21 July 2018 10:56:59(UTC)
fusionfaded

Switzerland   
Joined: 04/01/2018(UTC)
Posts: 33
Originally Posted by: kimballthurlow Go to Quoted Post


Actually there is no transition section (increasing height) in the curve itself.
The curve must have the same superelevation all the way, start to finish (tangent to tangent).

On a real railroad or road, the transition for banking, cant or superelevation is done on the straight (tangent) leading into the curve.
There is a calculation formula (r, speed) on what length is desirable, but it depends on maximum design speed and I can't remember it off-hand.


I strongly disagree with you. Whenever possible,the superelevation is changed in the transition curve between a straight tangent and the curve itself, not on the straight tangent. For Switzerland this is described in the "Ausführungsbestimmungen zur Eisenbahnverordnung" (Not sure about other countries). For model railroads, the NEM 114 also states that the superelevation should ideally be changed over the whole distance of the transition curve. Obviously this doesn't work to well with Märklin C-Track, since transition curves don't really exist to begin with.

Originally Posted by: kimballthurlow Go to Quoted Post

On a model train set with sectioned track (eg. C track), there is no need to worry about the superelevation on the straight (tangent) leading into the curve.
The reason is we are dealing with very small scale, and the lift given to the outer rail in the first curve section will raise the tangent piece effectively.
For the same reason a simple 2mm height is all that is needed for all curved pieces.
(For Mike C) And for the same reason it would not affect the placement for switches and S bends.

So the changes in super elevation would basically be achieved by having other pieces bend?

I'd also like to mention that according to NEM 114 the superelevation for 16.5mm gauge shouldn't be more than 1mm to prevent vehicles from tipping.
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Offline GlennM  
#29 Posted : 21 July 2018 11:40:29(UTC)
GlennM

United Kingdom   
Joined: 09/05/2011(UTC)
Posts: 2,877
Location: Somewhere, But Nowhere Near Manchester, England
It was my understanding (in road design and I am sure rail will be similar) the transition in preparation for the superelevated curve occurs in a horizontal transition section prior to the curve itself and that the curve is then elevated as required by the design and then there is a reverse horizontal transition section beyond the curve. As per Kimball's post above.

I am sure Dusan will clarify BigGrin BigGrin
Don't look back, your not heading that way.
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Offline kiwiAlan  
#30 Posted : 21 July 2018 14:22:06(UTC)
kiwiAlan

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Originally Posted by: Nigel Packer Go to Quoted Post
As a child, my mother always used to tell me: “There’s no such word as can’t”!

Nigel


You too ??? Laugh Laugh Laugh

Offline DV  
#31 Posted : 21 July 2018 14:58:38(UTC)
DV

Australia   
Joined: 29/11/2009(UTC)
Posts: 954
Location: Mount Barker, South Australia
Originally Posted by: GlennM Go to Quoted Post

I am sure Dusan will clarify BigGrin BigGrin


Thanks GlennBlushing Blushing Blushing

When I first started to learn how to design roads there was a formula you used to develop the correct amount of super elevation from standard road cross section (road with a crown) to the super elevated part of the curve. Unfortunately that was over 40 years ago, my memory of that is pretty hazy.

About 25 years ago we began using a computer program that did the calculations by us supplying the entrance and exit to the curve and the radius of the curve. If the radius was over a certain amount you could develop the 'super' up to the tangent point (as advised by Glenn and Kimball).

If the radius was of a small nature then the 'super' had to be developed by using a spiral entrance and exit to the the tangent points, if memory serves me correctly they were called Barnett curves from a book published by a gentleman called oddly enough Barnett. There were tables showing the radius and the length of spiral you required, which was fed into a formula.

Luckily, rail does not have to use spirals, as most radii in rail design are fairly large.

I agree for our model trains one should not start the full super elevation at the tangent points without lead ins/outs as that will cause all types of problems. Some length is required before the tangent points to develop the 'super'. How much? Well that's up to you, that's why I said I do it by trail and error and the old saying 'if it looks good, it must be good' I feel applies.

As to the amount of 'super' to the outside of the curve (stated before 2mm I think), again, depends on the length of the curve. A short curve might require a greater height to get the train at speed around the curve and then you would definitely require a transition lead in and a lead out.

In road design if the radius is small and the speed is low, then no 'super' is required, and I think you can apply that your layout as well. Then again if you don't do 'Scalextric' runs then you wouldn't require 'super'. It's up to the the individuals tasteThumpUp ThumpUp ThumpUp

But then what do I know about rail design...........enough to write on the back of a postage stamp in large capital lettersBlushing Blushing Blushing Blushing Laugh Laugh Laugh

So endeth the lessonLOL LOL LOL LOL LOL

I did put 'super' on my first modular layout after my ICE 3 went of the rails at high speed (it was a dare and I was stupid enough to accept it....doh!). By trail and error and I got the ICE around at the highest speed, BUT, funnily enough it depended on which car was at the start. I must admit that it does look really 'shmicko' when you see the loco coming round the super elevated bend.

Hope I didn't confuse anyone with my rantThumpUp ThumpUp ThumpUp ThumpUp
Dusan V
'I find your lack of faith (in Märklin) disturbing'
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Offline GlennM  
#32 Posted : 21 July 2018 15:38:27(UTC)
GlennM

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Originally Posted by: DV Go to Quoted Post

Hope I didn't confuse anyone with my rantThumpUp ThumpUp ThumpUp ThumpUp


Nope a top explanation ThumpUp ThumpUp
Don't look back, your not heading that way.
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DV
Offline fusionfaded  
#33 Posted : 21 July 2018 17:24:01(UTC)
fusionfaded

Switzerland   
Joined: 04/01/2018(UTC)
Posts: 33
Here's the NEM Standard for the Superelevation (Unfortunately only in German)
I made a translation of it, albeit it might not be perfect.
Quote:
Purpose and term
The superelevation serves the safe operation of vehicles in arcs, by partly or completly compensating the lateral acceleration caused by the arc, by elevating the outer rail by u compared to the inner rail. (Fig. 1)
In model railroading, superelevation isn't needed to compensate those effects, only increasing the chance of vehicles toppling over. Therefore, superelevation for optical purposes should not exceed G/15.

(A table showing gauges and the corresponding cant, 1mm for H0)

For rack railways, superelevation is usually absent or very small

2. modeling

In the curve of the track, the plane or inclination of the straight track is maintained for the inner rail, while the outer rail is elevated by u in relation to the level of the inner rail.
Track curves with cant should be constructed with transition curves (see NEM 113). The length of the superelevation ramp should correspond to the length of the transition bend. The rise to the cant is evenly distributed over the length of the transition bend (Fig. 2).



Quote:

If the radius was of a small nature then the 'super' had to be developed by using a spiral entrance and exit to the the tangent points, if memory serves me correctly they were called Barnett curves from a book published by a gentleman called oddly enough Barnett. There were tables showing the radius and the length of spiral you required, which was fed into a formula.

Luckily, rail does not have to use spirals, as most radii in rail design are fairly large.


Are you talking about "Transition Curves for Highways" by Joseph Barnett? Are those some special curves or are you referring to transition curves in general?
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Offline DaleSchultz  
#34 Posted : 22 July 2018 01:51:40(UTC)
DaleSchultz

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Posts: 3,997
BTW at HO scale the superelevation is for looks only. It does not help trains stay on the tracks.

A friend in the local train group did some experiments and even built special test devices to test Märklin HO scale trains on canted tracks.

His findings were that because of the low mass of the models, we would do better to in fact reverse the slope, so that the inner track was higher than the outer track because the draw bar force is so large that there is more danger of pulling the coaches off the track in a curve than there is any chance of them flying off the tracks due to centrifugal forces.

So if you are concerned about pulling a rake off the track inside a helix - tilt the tracks outwards!

For visible areas, add up to 2mm on the outer side so that the train twists prototypically as it goes through the curve. It is all cosmetics.

If you run a train Märklin off the tracks on a curve you are just going way too fast or the track is poorly laid. Especially with the over-sized flanges we have.
Dale
Intellibox + own software, K-Track
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Offline kimballthurlow  
#35 Posted : 22 July 2018 02:20:33(UTC)
kimballthurlow

Australia   
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Location: Brisbane, Australia
Originally Posted by: fusionfaded Go to Quoted Post
Originally Posted by: kimballthurlow Go to Quoted Post


Actually there is no transition section (increasing height) in the curve itself.
The curve must have the same superelevation all the way, start to finish (tangent to tangent).
On a real railroad or road, the transition for banking, cant or superelevation is done on the straight (tangent) leading into the curve.
..


I strongly disagree with you. Whenever possible,the superelevation is changed in the transition curve between a straight tangent and the curve itself, not on the straight tangent. For Switzerland this is described in the "Ausführungsbestimmungen zur Eisenbahnverordnung" (Not sure about other countries). For model railroads, the NEM 114 also states that the superelevation should ideally be changed over the whole distance of the transition curve. Obviously this doesn't work to well with Märklin C-Track, since transition curves don't really exist to begin with.

Originally Posted by: kimballthurlow Go to Quoted Post

On a model train set with sectioned track (eg. C track), there is no need to worry about the superelevation on the straight (tangent) leading into the curve.
The reason is we are dealing with very small scale, and the lift given to the outer rail in the first curve section will raise the tangent piece effectively.
..

So the changes in super elevation would basically be achieved by having other pieces bend?

I'd also like to mention that according to NEM 114 the superelevation for 16.5mm gauge shouldn't be more than 1mm to prevent vehicles from tipping.


Hi ff,
Thanks for your investigation on the NEM standard. That is really useful

Yes, you are correct when you say "...the superelevation is changed in the transition curve between a straight tangent and the curve itself...".
I did not mention the "transition curve.." because we are dealing with small scale models where curved trackage does not usually have a transition.
As you said " ...Obviously this doesn't work too well with Märklin C-Track, since transition curves don't really exist to begin with."
So for practical modelling most of us are dealing only with fixed radius curves.

And you are correct in the real railroads where curved transitions are MANDATORY, otherwise trains would never negotiate a "bend" or curve.
The horizontal transition in mathematical terms is a cubic parabola, like the spiral rings in a seashell.
And the radius from the straight starts at infinity, and gradually decreases to the "fixed" radius of the curve itself.
This must also be accompanied by a vertical transition in the outer rail, so the superelevation increases from zero at or before the tangent point, to the maximum in the fixed curve.

While the NEM standards mention transitions, they are rarely done in model layouts for practical reasons.
(In C track, a reasonable transition can be achieved for any R1-R4 curve by using the R5 as a start piece at both ends of the curve)
Regarding their 1mm standard, I disagree.
In successful layout building with large radius curves above 1 metre, I have used 2mm superelevation for two reasons:
1. it looks better
2. it works
I never had a train fall over.

You say "So the changes in super elevation would basically be achieved by having other pieces bend?"
My answer is yes in my opinion. It works fine on my C track layout.

Let us not forget that a main line railway curve is normally 1/2 a mile radius or more (804 metres +). (Molesworth Engineering Handbook, 34th edition, 1951)
In HO scale that is a radius of 9.25 metres, which is unavailable to 99.999% of model layout builders.
So we are talking overall of practical track-laying in miniature.

I am really glad that Maerklin and others have done all the hard work, and given us model track pieces that easily fit together, look fine, and work terrific.
And you don't need to know about cubic parabolas.

Kimball
HO Scale - Märklin (ep II-III and VI, C Track, digital) - 2 rail HO (Queensland Australia, UK, USA) - 3 rail OO (English Hornby Dublo) - old clockwork O gauge - Live Steam 90mm (3.1/2 inch) gauge.
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Offline kimballthurlow  
#36 Posted : 22 July 2018 04:31:53(UTC)
kimballthurlow

Australia   
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Location: Brisbane, Australia
I can only hope that Harvey who asked the original question in the topic, has been answered.

And probably in the first few replies. :-)

Kimball
HO Scale - Märklin (ep II-III and VI, C Track, digital) - 2 rail HO (Queensland Australia, UK, USA) - 3 rail OO (English Hornby Dublo) - old clockwork O gauge - Live Steam 90mm (3.1/2 inch) gauge.
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Offline GlennM  
#37 Posted : 22 July 2018 12:37:02(UTC)
GlennM

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Posts: 2,877
Location: Somewhere, But Nowhere Near Manchester, England
Originally Posted by: kimballthurlow Go to Quoted Post
I can only hope that Harvey who asked the original question in the topic, has been answered.

And probably in the first few replies. :-)

Kimball


LOL LOL LOL LOL LOL LOL LOL
Don't look back, your not heading that way.
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Offline fusionfaded  
#38 Posted : 23 July 2018 00:30:53(UTC)
fusionfaded

Switzerland   
Joined: 04/01/2018(UTC)
Posts: 33
Originally Posted by: kimballthurlow Go to Quoted Post


Hi ff,
Thanks for your investigation on the NEM standard. That is really useful

Yes, you are correct when you say "...the superelevation is changed in the transition curve between a straight tangent and the curve itself...".
I did not mention the "transition curve.." because we are dealing with small scale models where curved trackage does not usually have a transition.
As you said " ...Obviously this doesn't work too well with Märklin C-Track, since transition curves don't really exist to begin with."
So for practical modelling most of us are dealing only with fixed radius curves.

And you are correct in the real railroads where curved transitions are MANDATORY, otherwise trains would never negotiate a "bend" or curve.
The horizontal transition in mathematical terms is a cubic parabola, like the spiral rings in a seashell.
And the radius from the straight starts at infinity, and gradually decreases to the "fixed" radius of the curve itself.
This must also be accompanied by a vertical transition in the outer rail, so the superelevation increases from zero at or before the tangent point, to the maximum in the fixed curve.

While the NEM standards mention transitions, they are rarely done in model layouts for practical reasons.

There's still flexible K-track or the possibility of equipping other flex-track with stud-contacts, for a realistic layout. Tongue
But I am aware that many of us don't have the possibilities to model a realistic curve. Still, for the prototypical side of this issue, the change in super-elevation doesn't usually happen on a straight. Now, obviously when we look at model trains, this cannot be applied 1:1. And then you can make the decision where you start your superelevation.
Personally, I find it weird when my trains start rolling before actually starting to turn, which is something you don't see in real trains. I therefore decided to add the superelevation in the first curve, despite not being prototypical either.

Originally Posted by: kimballthurlow Go to Quoted Post

Regarding their 1mm standard, I disagree.
In successful layout building with large radius curves above 1 metre, I have used 2mm superelevation for two reasons:
1. it looks better
2. it works
I never had a train fall over.

In regards to the height of the cant, I've been using 2mm cardboard too and don't think it caused any issues either. But at least from the perspective of a manufacturer it might make sense to follow the rather conservative standard to ensure compatibility with everything. If that would happen, you'd still have to add 1mm cardboard.

Originally Posted by: kimballthurlow Go to Quoted Post

You say "So the changes in super elevation would basically be achieved by having other pieces bend?"
My answer is yes in my opinion. It works fine on my C track layout.

Doesn't sound too stable tbh, I'd rather use separate transition pieces, especially for temporary layouts on the floor.

Funfact: The old Gotthard and Lötschberg lines have a minimal radius of 300m, the Semmering line in Austria even gets down to 200m
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Online Harvey  
#39 Posted : 23 July 2018 02:21:34(UTC)
Harvey

United States   
Joined: 17/02/2008(UTC)
Posts: 591
Location: Glen Oaks, N.Y.
Originally Posted by: TEEWolf Go to Quoted Post
Originally Posted by: Harvey Go to Quoted Post
The current issue of Marklin Magazine (June/July 2018) mentions on page 48 'A cant given to the outer rails on curves offers a more realistic appearance and improves operational safety when you get to grips with such kinks.

The explanation is very brief and unclear - obviously this the article assumes greater knowledge by the reader, which I don't have. Does anyone have a link to an instructional video? Or explanation?

Regards
Harvey


Hi Harvey,

in the German Version of the MM 03/2018 page 48 is the first part of the article (great driving experience) about the MS 2.

To which article does your question refer? Is it the one "electronic milestone", the "project digital track" describing the ETCS system? (This is at the German Issue on page 94 et seqq). Or another one? Or does your issue have even articles which are not in the German issue?

Thanks

Regards

Wolfgang


Wolfgang,

My June/July issue (English), on page 46 starts Part 3 of 'Tracks and COntrol'. The mobile station article (Part 2) titled Just Start, begins on page 32. Go figure, similar issues have different articles.

Harvey

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Offline kimballthurlow  
#40 Posted : 23 July 2018 02:25:15(UTC)
kimballthurlow

Australia   
Joined: 18/03/2007(UTC)
Posts: 6,653
Location: Brisbane, Australia
Originally Posted by: fusionfaded Go to Quoted Post
...
There's still flexible K-track or the possibility of equipping other flex-track with stud-contacts, for a realistic layout. Tongue
But I am aware that many of us don't have the possibilities to model a realistic curve. Still, for the prototypical side of this issue, the change in super-elevation doesn't usually happen on a straight. Now, obviously when we look at model trains, this cannot be applied 1:1. And then you can make the decision where you start your superelevation. .....


Hi ff,
Thanks for that.
In a previous life I built extensive 2 rail layouts and modules for Club and myself.
I used flexible track, and always modelled the transition and superelevation, usually upward of 1m radius. It was magnificent.

The superelevation always started on the transition curve side of the tangent point, just like in the prototype as you say.
In my opinion fixed radius requires a slightly different approach. But anyway these are our models and we do what we like.

Kimball
HO Scale - Märklin (ep II-III and VI, C Track, digital) - 2 rail HO (Queensland Australia, UK, USA) - 3 rail OO (English Hornby Dublo) - old clockwork O gauge - Live Steam 90mm (3.1/2 inch) gauge.
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Online Harvey  
#41 Posted : 23 July 2018 02:32:29(UTC)
Harvey

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Joined: 17/02/2008(UTC)
Posts: 591
Location: Glen Oaks, N.Y.
Originally Posted by: kimballthurlow Go to Quoted Post
I can only hope that Harvey who asked the original question in the topic, has been answered.

And probably in the first few replies. :-)

Kimball



I have placed cardboard under some curve tracks and so I have canted. What I don't understand is the need to and how (where, how much, etc) to notch the track with a handsaw and bend the track upward. (paraphrasing the article.

I'll look at the links and see if that is explained.

Regards
Harvey

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Offline DaleSchultz  
#42 Posted : 23 July 2018 04:53:18(UTC)
DaleSchultz

United States   
Joined: 10/02/2006(UTC)
Posts: 3,997
no need to cut or bend the rails. So long as the other rail is higher than the inner one, it will look great.
Dale
Intellibox + own software, K-Track
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Offline kimballthurlow  
#43 Posted : 23 July 2018 06:04:19(UTC)
kimballthurlow

Australia   
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Posts: 6,653
Location: Brisbane, Australia
Originally Posted by: fusionfaded Go to Quoted Post
...
In regards to the height of the cant, I've been using 2mm cardboard too and don't think it caused any issues either. But at least from the perspective of a manufacturer it might make sense to follow the rather conservative standard to ensure compatibility with everything. If that would happen, you'd still have to add 1mm cardboard.

...


Actually ff, if you use an engineering formula to calculate superelevation, you get the following results:
100kmh on a radius of 800 metres on standard gauge track = superelevation E of 146mm (= 1.7mm in HO gauge).
Slower or faster will give a different result.

I think (as does yourself, Harvey and Dale) that 2mm works well.

Kimball
HO Scale - Märklin (ep II-III and VI, C Track, digital) - 2 rail HO (Queensland Australia, UK, USA) - 3 rail OO (English Hornby Dublo) - old clockwork O gauge - Live Steam 90mm (3.1/2 inch) gauge.
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Offline DV  
#44 Posted : 23 July 2018 06:11:30(UTC)
DV

Australia   
Joined: 29/11/2009(UTC)
Posts: 954
Location: Mount Barker, South Australia
Originally Posted by: fusionfaded Go to Quoted Post

Are you talking about "Transition Curves for Highways" by Joseph Barnett? Are those some special curves or are you referring to transition curves in general?


Yes. No. Yes.

Hope this has answered your questionsBigGrin ThumpUp
Dusan V
'I find your lack of faith (in Märklin) disturbing'
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Offline Bones  
#45 Posted : 12 March 2019 03:55:38(UTC)
Bones

Australia   
Joined: 15/09/2015(UTC)
Posts: 105
Location: Queensland
Hello All

Just thought I'd add my 2 cents worth

Cant or super elevation serves two purposes

1. When travelling at high speed the train will tend to lean outwards on a curve and by canting the track it helps keep the wagon or carriage from hitting the inner walls of tunnels

2. It helps reduce the wear on the outside wheels of a wagon or carriage as the curve tightens from the straight

From my point of view it's really not necessary on a layout since the centrifugal forces aren't that significant and most outside observer's wouldn't notice anyway
BigGrin
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Offline DaleSchultz  
#46 Posted : 12 March 2019 15:56:40(UTC)
DaleSchultz

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Joined: 10/02/2006(UTC)
Posts: 3,997
Originally Posted by: Bones Go to Quoted Post

From my point of view it's really not necessary on a layout since the centrifugal forces aren't that significant and most outside observer's wouldn't notice anyway
BigGrin


Indeed the models do not need it for wear and centrifugal forces. In fact a train friend did all the physics of it and found that at HO scale with the very light mass of our trains, we would actually do better with a reverse superelevation (inner rail higher) to prevent trains being pulled off curved tracks by the drawbar forces.

However, I think you are missing the point by assuming that the reasons it is done in the model are the same as the reasons it is done in the prototype. This is not so.

A side effect of doing superelevetaion in the prototype, is that the train twists longitudinally as it transitions from non-superelevated ares and vice versa.

By doing the superelevation in the model it has the same effect, and thus makes the motion and visual gestalt of the train match the prototype. i.e. it looks much more realistic.
Dale
Intellibox + own software, K-Track
My current layout: https://cabin-layout.mixmox.com
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Offline Ian555  
#47 Posted : 12 March 2019 17:38:29(UTC)
Ian555

Scotland   
Joined: 04/06/2009(UTC)
Posts: 20,235
Location: Scotland
Photo shows Bing O gauge clockwork track from the early 1900's with built in Cant.

Ian.

UserPostedImage
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Offline DaleSchultz  
#48 Posted : 12 March 2019 18:21:46(UTC)
DaleSchultz

United States   
Joined: 10/02/2006(UTC)
Posts: 3,997
I often wonder why the train manufacturers don't build in some superelevation on their curves. I guess it is the transition from curve to straight that would be a little problematic, but I am sure straight sections could absorb a bit of height on one edge.
Dale
Intellibox + own software, K-Track
My current layout: https://cabin-layout.mixmox.com
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Offline Bones  
#49 Posted : 04 April 2020 02:09:15(UTC)
Bones

Australia   
Joined: 15/09/2015(UTC)
Posts: 105
Location: Queensland
My reference to volvo's was because my now dearly departed brother didn't like them

On a small section of the M1 in Brisbane they deliberately reversed the camber on the road thinking it would slow the cars down

Two salient points arise from this - Since the cars are controlled by human's and they tend to do stupid things it failed miserably
Most people when they drive couldn't give a tinker's cuss about how the road was built they only know it's for you to drive on failed miserably
there too



Originally Posted by: GlennM Go to Quoted Post
Originally Posted by: xxup Go to Quoted Post
In Australia, the slope of a road from the center line is called Camber.. it's main purpose is for water drainage. On a two-way highway, the road's camber will start from the outer edge on a high-speed curve - Australian Engineers call this the bank angle of a curve or sometimes a banked turn - it stops Volvos from sliding off the road when it rains.. RollEyes

I am pretty sure that super-elevation is an American term..Cool


IMHO based on my construction experience;

In UK road construction the camber is the curvature of the road surface itself, the primary reason for camber is to allow for drainage of water from the surface. The highest point of the camber is known as the crown.

Whereas superelevation is the vertical distance between the height of inner and outer edges of the road surface (or inner and outer rails of rail track). The primary reason for superelevation it is to counter act centrifugal forces acting upon vehicle. Superelevation is often more commonly know as 'banking'.

The combination of superelevation and camber will be down to calculations undertaken to determine likely rain fall. The movement of excess amounts of water across a superelevated surface can lead to vehicles aquaplaning.

I am unaware of the origin of the term superelevation but I can assure you that it has been in common use in UK construction for at least 100 years

It is therefore correct that superelevation is there to stop Volvos (and other vehicles) from sliding off and loosing control, but in reality it is camber than possibly leads to more actual accidents, in particular in roadworks, which is one reason in roadworks when changing road surfaces or changing from one carriageway to another, the speed is reduced, because sudden camber changes, or adverse cambers, or reverse cambers can cause loss of control at speed, and if you add inclement weather into the equation the likelihood is even higher.

Drive safely

BR


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