Loco's stop/ stop starting in black spots.

[Railway_Ron]

Hi Guys'

I am new to this DCC concept, but I'm slowly getting my head around it. I have an 8 x 6 foot, 3 ring layout. I laid it all out first, checked it - yes, power to all parts of the layout. Tested it (I'm using Hornby eink) with 2 loco's running

 

around in different directions crossing points an so on, 2 loco's on the same line. All worked well.

I have began to fasten the track down and started creating scenery for my layout and test it at regular intervals, but I have now noticed that on the back

 

straight the loco's hit a specific spot and the loco's either stop fully or they have intermediate stop start at slow to medium speed. The only way they keep running is if they are at almost full speed. Tested the track and there is power, its even got power

 

directly under the loco where it has stopped. I have cleaned the track with a track rubber, lightly sanded the rails to ensure that there is no clue of paint on them, I've even been along with white spirits - but the trains keep on stopping and I don't know

 

why. I have spoken to a local stockist how suggested that I may not have enough power. To check this I have created just the 1 single track and an the loco again, still has stop start issue's. It's not a particular loco that's a fault, as it does it no matter

 

which one I run on this line. Has anyone got any Ideas?

 

[Fishmanoz]

Hi RR, for a start, take that piece of sandpaper and throw it in the bin. Sanding leaves fine scratches that accumulate dirt, not a good idea at all. Isopropyl alcohol is the suggested cleaner, either bought straight or as part of any number of proprietary

 

cleaners.

 

The only thing I can think of is that one track section doesn't have good contact from fishplates at either end and so has current limitations. Is that a possibility?

[58001]

I agree, it doesn't take much to upset the digital signal. I have one blackspot on my layout that upsets a few locos working on DCC, the track isn't completely level so there is a small step between two sections of track. That can be enough to interrupt

 

the signal.

To test you connection identify the join nearest the point at which the loco stutters using a short piece of wire slid between the rail underside and the sleeper ensuring good contact with the underside of the rail(just like a power clip). This

 

will ensure a good electrical connection. Do this to both rails and see if the problem is resolved or not.

 

[Railway_Ron]

Fishmanoz said:

Hi RR, for a start, take that piece of sandpaper and throw it in the bin. Sanding leaves fine scratches that accumulate dirt, not a good idea at all. Isopropyl alcohol is the suggested cleaner, either bought straight or as

part of any number of proprietary cleaners.

The only thing I can think of is that one track section doesn't have good contact from fishplates at either end and so has current limitations. Is that a possibility?

Thanks for the suggestions.

I was considering taking the track up as a last resort, I'll check out the fishplates.

[Railway_Ron]

58001 said:

I agree, it doesn't take much to upset the digital signal. I have one blackspot on my layout that upsets a few locos working on DCC, the track isn't completely level so there is a small step between two sections of track. That

can be enough to interrupt the signal.
To test you connection identify the join nearest the point at which the loco stutters using a short piece of wire slid between the rail underside and the sleeper ensuring good contact with the underside of the rail(just

like a power clip). This will ensure a good electrical connection. Do this to both rails and see if the problem is resolved or not.

I had problems with the points previously, but found it best not to fasten them down and I used a thin sheet

of card underneath resolved this problem. I'll give your idea a try. Thanks.

[Culp]

You can get odd things happen with a digital signal. A few things I would check are:-

1. check the way any points are included in the layout. There is lots of advice on the net about this but to be safe always feed power in from the 'bottom' of the

 

letter Y shape and insulate the others (If you read the many help pages there are much better ways and they aren't hard - but for starter this works)

2. consider breaking the oval into sections with rail insulators and using a power line to each section.

 

This creates independent sections.

 

I find this really good as later when odd sections 'go down' you can track back to where the problem is. Look up POWER BUS on the net. Effectively it is a pair of good quality cable running under the board and with

 

links up the track at intervals. As each section is independent ----It makes sure that you have a good supply of power to each section rather than rely upon fishplates to send the power round the whole network and cause interference . This way power is run

 

perhaps over two or three fishplates only.

 

Finally you can get problems like this on DC so it has got to be possible on DCC where as others have said the odd distortion!!!

 

NB fishplates that are Ok today may not be next miknth!

 

Power Buses

 

are really the way to go if like me your layout will develop and adapt and it is so easy to forget where that feed came from.

[Fishmanoz]

Culp, there is no need to make separate sections of a layout with DCC, in fact insulated rail joiners should only be used with reversing loops, boosters or live frog points as per their instructions. Otherwise leave as a single section.

 

DCC bus

 

is considered best practice but a single connection and DCC point clips work long term for many. And with either of these, there is no need to feed a point from a particular end.