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Advice on wiring a fiddle yard for reversing Track and electrical/DCC
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Active Member 84 posts NormanW Active Member 84 posts
NormanW

Please may I ask for members expert advice on how I should wire my proposed fiddle yard correctly for DCC?

This will be my first DCC layout.  I have read and understand the principles and have seen and used DCC in operation, but this fiddle yard will involve reversing direction.  My plan for the non-scenic fiddle yard is below. I think I will need an auto reverse circuit and a power boost, but I am not really sure.

rds%20V3.png 

The design fits my rail room shape.  The grey area is the reinforced concrete house support (immovable object) end of the 5 metre (15ft approx) long scenic section, and is where the fiddle yard joins at 90 degrees through a scenic break..  At the other end of the scenic run is a rotating sector plate, which will hold trains of 900mm length, maximum, so the length of each spur in the fiddle yard is 1 metre.

The direction of travel of trains is clockwise.  There are three possible train movements.

1)  A train can run round the loop completely and back out onto the scenic section, changing direction from Up Main, to Down Main, but without actually altering its direction of travel or entering the fiddle yard.

2)  A train can use the turnout at 'A' to enter the fiddle yard from the Up Main and then be directed into a spur.

3)  A train can enter the yard via the curved turnout at 'D' and then reverse into a spur.

The small black arrows indicate where I think the fiddle yard needs isolating.

To follow normal UK practice of left track (clockwise) running, to get a full length train from the fiddle yard onto the main line, a train in spur 1, would reverse through the three way turnout 'B', across the turnout 'A' then once the locomotive is clear of the three way, it would change direction to move forward and out onto the main line at turnout 'C'.  Shorter length trains, and those stabled further up the ladder could reverse inside the yard confines and out via turnout 'C'.  So far so good, as all of those movements follow the clockwise running principle, but the yard at turnout 'D' would have to be isolated.

In one of my early plans I had put a single slip crossover at turnout 'A', but I simplified it, accepting an un proto-typical need to reverse part of a train through the turnout to get it clear of the three way.

Also, I could of course simply do away with turnout 'D', so the whole yard is always in clockwise running order.

I have included turnout 'D', more for flexibility as a just-in-case, so I can get a train off the main at 'D' and then reverse it into a spur.  This would be the time when reversing the running direction in the fiddle yard would be required, with of course the isolation at turnouts 'A' and 'C'.  

The constraints of dense reinforced concrete pillars restrict what I can do in terms of layout shape and the 'L' shape with the rotating sector plate gives me the best options for a good operational length to run.  I have purchased an NCE Power-Pro system as my DCC of choice, so will be installing NCC gear..

My scenic section is modeled in and around the station at Redmire on the Wensleydale Railway, a UK Heritage branch line in deepest North Yorkshire.  Trains tend to be short.  The YouTube video gives a nice view of the railway today

 

These link to the Wensleydale Railway websites

http://en.wikipedia.org/wiki/Wensleydale_Railway
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http://www.wensleydalerailway.com/
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http://www.wensleydalerailwayassociation.com/
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Any suggestions would be welcomed.

Norman
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rocdoc Regular poster 190 posts
rocdoc

Reverse fiddle yard

G'day Norman

I think you're making things unnecessarily awkward for yourself with that design. The location of the 3 way points is a big problem as they form a reverse loop which must be gapped where you have shown, but then to shunt on the Up to the left of them means going in and out of that block. I would suggest simplifying the design in order to also simplify the wiring (and incidentally reduce the number of turnouts required) as follows: Do away with turnouts A, B, C and D so that you are left with a single loop of track that enters the yard as the Up line and leaves it as the Down. Stub sidings can be placed anywhere you like within the loop, and can be more or less situated where you have them at present, but without siding 1 because you've lost turnout B. Then place your gaps in both tracks somewhere around the position of the green arrows (to allow room for shunting the stubs), thus making the loop and its included sidings one block which requires the reversing unit.

Further, I would consider making some or all sidings into double ended loops (or sidings I think for our American friends) for added flexibility, but keeping them all within the same block. I have done this and it works a treat.

Best of luck

Tony in Australia
Tony in Gisborne, Australia
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HVT Dave Prolific poster 1,213 posts
HVT Dave

Suggest 3 changes

Hi Norman,

I make 3 suggestions.

1 - Move turnout A to the left far enough to lengthen the center track so that a train can back out of the spur 1 without fouling the main line.

2 - Make one reversing section from the right leg of the 3-way switch to the diverging leg of D.  It would include 6 spurs.

3 - Make a second reversing section from the continuing leg of D on the Down Main Line longer than your longest train.

That should simplify wiring.

Regards,

Dave

Dave

Member of the Four Amigos

 
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NormanW Active Member 84 posts
NormanW

Reverse fiddle yard

Hi Tony

Thank you for your constructive comments.  I have a constraint in that the width of the fiddle yard is 800mm, so there is just room for 4 pieces (180 degree turn) of 370 degree 1st radius track.  This means the potential for double ended loops is reduced.  But this is what I have drawn, which is I think what you mean.

rds%20V4.png 

Removing the 3-way is a good idea.  I can get one loop in, as at the top, or just leave it simple, as at the bottom.  Using flexi track (as I don't intend hand building this track) I could get a second curved loop, but it would be VERY tight.

Was this what you were suggesting?

 

Norman

 
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