Large Corner Layout Complete Track Question

[WestRail 642fan]

So, has R7277 'Large Corner Layout Complete Track' bee retired already? Its still listed as pre-order but when viewing its page, it says its out of stock with no new stock to arrive. I was looking forward to buy this honestly.

[Going Spare]

A quick internet search shows it still available from a number of retailers.

[Chrissaf]

But before you expend the amount of money this layout costs. It would be prudent for you to research this design and understand that it has numerous 'Reverse Loops' in it that generate 'short circuits'. Easy enough to resolve on a DCC layout, but not so easy to resolve on an Analogue DC one.

 

See these previous threads.

 

Hornby R7277 Large Corner Layout DCC Reverse Loop solution.

https://www.hornby.com/uk-en/forum/post/view/topic_id/30963/?p=1

 

Hornby R7275 Small Corner Layout DC Reverse Loop Solution.

https://www.hornby.com/uk-en/forum/r7275-layout/?p=1

 

[Rog RJ]

Basically, a badly designed layout that needs a fair bit of time and money spending on it to make it fit to use.

[WestRail 642fan]

hmmm :/ looking and the other forum posts and it does seem to be flawed plan, quite the same really, it peaked my interests

[JJ73]

Good news (Kinda) This Layout is also on Pages 58-59 of the Track Plans Edition 14...

 

/media/tinymce_upload/8969ba016ab9f190b003b7147de0f41e.png

 

/media/tinymce_upload/9abcbc17d4972a432a58a385a4344c5c.png

[JJ73]

If you can think that you can get it to work  - then those are all the bits above to get!!! Well you did say "it peaked my interests"!!!

[Derek 19B]

@Blue992

If the track plan has your interest go for it ! You know it has issues before you start. Treat yourself to a multimeter and go for it slowly, get one loop running at a time , and test , before adding a new section test then connect the new section and test. Test everything before and after be prepared to take things up .

Just think the rails are one red one black and they don't go together.

Accept the challenge and go for it .

Derek 19b

[WestRail 642fan]

i am/was intending to use this layout in DC only, would using isolating rail joiners help leaviate the short circiting issues faced when using DCC on the same layout?

[Chrissaf]

No not really, you need to get a handle [understanding] on why and how a 'Reverse Loop' creates a 'short circuit'. All adding IRJs will do is prevent the 'short circuit' being there all the time. Once a metal wheel of any rolling stock bridges across the IRJ, the metal wheel will bridge two different rail polarities and trigger the short.

 

Although written for DCC, my Reverse loop Tutorial document will provide a good grounding in the issues to be consided when dealing with reverse loops.

 

The only saving grace is that in a DC Analogue layout using Hornby points, the Hornby points are 'self isolating'. And in the case of the Hornby R7277 layout design, there are numerous points in the route of the reverse loops. This means that subject to which points are switched in what route that the 'short circuits' will appear random and ad-hoc in nature. Whereas, in a DCC layout where all track is all live [DCC point clips fitted to the points], the 'shorts' will be permanent.

 

But there is also something else that nobody has yet mentioned regarding the R7277 layout when used in a DC Analogue layout. The distribution of the controller power to the track. Power should always be applied to the common end [toe end] of a point, else you end up with 'dead track' sections. The R7277 layout design is a very complicated design with lots of points and will need an awful lot of design skill to devise a DC Analogue power distribution plan that not only deals with the 'reverse loops' but also eliminates dead track sections. This R7277 layout design is not really suitable as a starting project for novices.

 

You can download my PDF tutorial from here:

https://btcloud.bt.com/web/app/share/invite/TVjeV58CqN

 

[5Dublo2]

You will need Insulating Rails Joiners for both DC(analog) and DCC (Digital) operation.

 

For DC (Analog) operation, as locos and other metal wheeled rolling stock crosses over the insulated joiners, when entering or leaving the reverse loop, a short circuit will still occur, so as well as isolating sections of track in the loops you still have to use polarity reversing switches to manage the power inside the reverse loops to match the power outside the loop at the point that the train enters or leaves the loop.

 

For DCC (Digital) operation the Automatic Reverse Loop Module actually makes use of the loco briefly shorting out the circuit as it crosses an insulated join, as this short is detectable by the module which then flips the polarity,  all within a fraction of a second and before the short has chance to cause any other issues.

 

I suspect it will get very interesting/complicated (but not copletely impossible) if you try to mix DCC and DC control in a layout with multiple reverse loops like this one 

 

EDIT: I think I was answering while someone else also was, so my comment relates to the query about using insulators with DC to avoid ths problem seen with DCC

[The Doc]

Here are the areas causing problems with this layout:

/media/tinymce_upload/72dc3e54e4ad823cbf91f3c9458f9e26.png

 

And here one simple solution to avoid short circuits (omit the features causing problems):

/media/tinymce_upload/f505532a959763789f174eeada8fe649.png

I hope that helps a little.  As this post has to be held for approval, someone else may get in with other ideas first.

[WestRail 642fan]

Here are the areas causing problems with this layout:

/media/tinymce_upload/72dc3e54e4ad823cbf91f3c9458f9e26.png

 

And here one simple solution to avoid short circuits (omit the features causing problems):

/media/tinymce_upload/f505532a959763789f174eeada8fe649.png

I hope that helps a little.  As this post has to be held for approval, someone else may get in with other ideas first.

I was planning of removing most if not all of the sidings thats are inside the mainline loop

[Simmo009]

I think it is very poor of Hornby to no longer indicate power input locations in their track plans. To be fair, they do indicate which ones are not analogue suitable. People of all skill levels will always be drawn to the more complex layouts, and will get very frustrated when the thing won't work. This could turn people away from the hobby, which is to nobody's benefit. Maybe a difficulty rating for various aspects would be beneficial. 

[The Doc]

@Blue922

Surely you can never have too many sidings, because you can never have too many trains? 😆

[Going Spare]

But if all you are thinking of using are the two main ovals, does it make financial sense to buy the pack in the first place?  The turntable alone is around £70.