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Discussion Starter · #1 ·
Hi folks

Since my postings a few months ago, I have been adding track to my somewhat small layout! It is taking time since the cost is a bit tough to swallow!


Anyhow, I have a technical question... my understanding with DCC is that I do not have to isolate tracks as the complete layout is fed by the controller, and the digital signals can therefore reach any train on any track. This being the case I assume that electrofrog points can and are preferable for smooth operation. I have a couple of insulfrog points and the train tends to get a bit stuck unless you have enough power to take the engine over the insulating parts. Are there any problems with using electrofrog points on DCC layouts? Are there any issues with shorting if a point is switched over for example? Thanks in advance...

cheers
HM
 

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Basically, when using DCC you do not have to have any insulated sections of a simple layout.

Opinions vary but you will achieve smoother running using electrofrog and some form of external switching. The contacts on the points themselves will almost certainly give problems at some stage.

Should you cause a short by running a locomotive the "wrong" way through a trailing point the controller will cut the power very quickly.

If you use insufrog points wheel flanges can sometimes cause a momentry short if they bridge the tiny gap as they move over the frog area.
 

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Discussion Starter · #3 ·
Hi Brian

Thanks for your reply. I just need some further clarification...

"Opinions vary but you will achieve smoother running using electrofrog and some form of external switching." - by "external switching" I take it you mean electrical switching of the actual point?

"The contacts on the points themselves will almost certainly give problems at some stage." - by "problems", what sort of problems do you mean for example?

"trailing point" - sorry I don't understand what you mean by this, please explain, thanks.

How is it possible to run a loco through a trailling point the "wrong way"?

Sorry, new to this and all this terminology!

Thanks
HM
 

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QUOTE (hawkmoth @ 10 Jun 2008, 18:20) <{POST_SNAPBACK}>Hi Brian

Thanks for your reply. I just need some further clarification...

"Opinions vary but you will achieve smoother running using electrofrog and some form of external switching." - by "external switching" I take it you mean electrical switching of the actual point?

"The contacts on the points themselves will almost certainly give problems at some stage." - by "problems", what sort of problems do you mean for example?

"trailing point" - sorry I don't understand what you mean by this, please explain, thanks.

How is it possible to run a loco through a trailling point the "wrong way"?

Sorry, new to this and all this terminology!

Thanks
HM

***Hi

The way Electrofrog is supplied "in the box" by Peco works but long term it will give some reliability issues, as will their insulfrog for that matter.

Peco make it easy to make some simple mods to the current electrofrog points. They are explained (sort of) in their instructions.

These are

(1) They leave a gap in the webbing under the point to make it easy to electrically bond together the stock rails and their adjacent closure rails - this bonding should be done

(2) they provide a simple cuttable wire link to join the closure rails and the part of the closure that forms the knuckle/common crossing - these links should be cut to make the whole frog area electrically separate from the rest of the point

(3) they provide a wire tail at the frog to solder a wire to. Connected via aswitch, this allows the frog polarity to be powered according to the way the point is set.

To switch the frog polarity you need wither a peco switch addded to the point motor or any other product that will carry out this function.

Making these mods is well worth doing as it will result in a far more reliable layout that will not let you down and allow stalling due to loss of contact anywhere, shorts due to differential in stock and closure rail polarity or loss of contact between point blades and stock rail.

regards

Richard Johnson
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Peco make it easy to make some simple mods to the current electrofrog points. They are explained (sort of) in their instructions.
These are

(1) They leave a gap in the webbing under the point to make it easy to electrically bond together the stock rails and their adjacent closure rails - this bonding should be done

(2) they provide a simple cuttable wire link to join the closure rails and the part of the closure that forms the knuckle/common crossing - these links should be cut to make the whole frog area electrically separate from the rest of the point

(3) they provide a wire tail at the frog to solder a wire to. Connected via aswitch, this allows the frog polarity to be powered according to the way the point is set.

To switch the frog polarity you need wither a peco switch addded to the point motor or any other product that will carry out this function.

Making these mods is well worth doing as it will result in a far more reliable layout that will not let you down and allow stalling due to loss of contact anywhere, shorts due to differential in stock and closure rail polarity or loss of contact between point blades and stock rail.

Using peco code 55 electrofrog point i power the toe and insulate the centre rails coming out of the point picking up power on all four rails after the point would this give the same performance and reliability as bonding the stock and closure rails?
 

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QUOTE (upnick @ 12 Jun 2008, 04:41) <{POST_SNAPBACK}>Peco make it easy to make some simple mods to the current electrofrog points. They are explained (sort of) in their instructions.
These are

(1) They leave a gap in the webbing under the point to make it easy to electrically bond together the stock rails and their adjacent closure rails - this bonding should be done

(2) they provide a simple cuttable wire link to join the closure rails and the part of the closure that forms the knuckle/common crossing - these links should be cut to make the whole frog area electrically separate from the rest of the point

(3) they provide a wire tail at the frog to solder a wire to. Connected via aswitch, this allows the frog polarity to be powered according to the way the point is set.

To switch the frog polarity you need wither a peco switch addded to the point motor or any other product that will carry out this function.

Making these mods is well worth doing as it will result in a far more reliable layout that will not let you down and allow stalling due to loss of contact anywhere, shorts due to differential in stock and closure rail polarity or loss of contact between point blades and stock rail.

Using peco code 55 electrofrog point i power the toe and insulate the centre rails coming out of the point picking up power on all four rails after the point would this give the same performance and reliability as bonding the stock and closure rails?

***No: The only way to get maximum electrical benefit and optimise reliability is to modify the point itself - this is equally true for both the N and 00/H0 scale pointwork. You must keep all rail live and remove dependence on rail and point blade contact completely. see the detailed description below - it applies equally to all scales and both DC and DCC layouts

---------------------------------

Peco code 75 turnouts are actually now made wiring them correctly easier but they still need a few minor modifications.

The objective is to divide the turnout up into 3 electrically separate areas: the two stock rails and related closure rails (which remain powered always) and the crossing Vee which is fed via a switch, the polarity of which is determined by the position of the turnout.

The first modification is to break the wire jumpers on the underside of the turnout marked with yellow lines. On the top side, there is already an insulated break in the rails.

Code 100 turnouts don't have this insulated break, therefore it's necessary to use a cutting disc to cut the rails. The next modification is to electrically bond the switch rails to the stock rails, marked by red lines. There's a gap in the sleeper webbing to help you do this. On older Peco products such as code 100, it is quite easy to cut the same gap using a knife.
The purpose of this modification is to remove the reliance on the switch blades making electrical contact with the stock rails. It also ensures that the switch rails are always at the polarity of their neighbouring stock rail and therefore stops any shorting (sparking) occuring between them due to out-of-gauge or course scale wheels.

In the picture there is a Peco switch as these are often used because they fit easily to Peco motors. Any switch will be suitable so long as it is a two-way switch. (Single Pole Double Throw type)

The wiring should be connected to the switch as shown by the red and blue lines.

Finally, insulated fishplates should be fitted to both of the crossing V rails, marked with green lines. This ensures that the entire crossing V area is a single electrically isolated unit with its own feed. This prevents the turnout causing shorts due to back-feeding.
The turnout is now ready for installation on your layout.

While its shown applied to a Peco product, the technique is exactly the same as for hand-made turnouts, no matter how they are made. The technique applies equally to all model scales, although is more difficult to implement in the smaller scales such as 'N'.

This is the ONLY correct way to wire live frog turnouts, regardless of scale, DC or DCC.

I've attached an image of a peco point and the changes needed

Regards

Richard
DCCconcepts
 

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Hi Richard,

Thanks for the information very useful.
 

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Hi Richard,

I might be wrong but I think you'll find that the construction of the Peco Code 55 points (N Gauge) is slightly different.

The hinge connection between the closure rails and the 'V'/frog is metal so the closure rails are connected electrically to the frog. The polarity of the closure rails is therefore changed when the frog polarity is changed and does not rely on contact with the stock rails to provide power to them.

I use the Seep PM1 point motors which are wired to change the frog polarity automatically.

Trevor.
 

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QUOTE (Expat @ 12 Jun 2008, 23:18) <{POST_SNAPBACK}>Hi Richard,

I might be wrong but I think you'll find that the construction of the Peco Code 55 points (N Gauge) is slightly different.

The hinge connection between the closure rails and the 'V'/frog is metal so the closure rails are connected electrically to the frog. The polarity of the closure rails is therefore changed when the frog polarity is changed and does not rely on contact with the stock rails to provide power to them.

I use the Seep PM1 point motors which are wired to change the frog polarity automatically.

Trevor.

*** Trevor I've modded many in both scales: Electrically they are actually almost exactly the same as the OO ones in the picture.
The N scale ex factory have the closure rails connected to the frog, and therefore they are the same polarity, and they should be separated and different polarities.

That is a key point of the modification, as leaving them like this with the closure rail and frog as one piece leaves the adjacent stock and closure rails at opposite polarities which they should not EVER be as it is a recipe for problems with easy derailment based / back to back based shorts.

For best practice the frog, left and right closure rails should ALWAYS each be electically separate and the adjacent stock and closure rails ALWAYS permanently bonded. Even blind and stubborn Peco really acknowledge this by making it so easy to do it right in their latest point tooling/assembly.

In your setup you are half doing the job really: yes, polarity is changed with the change of blade position but you are leaving the opposite polarity thing to happen and it will cause you operating grief long term. the extra mods actually take 5 only minutes!

Richard

PS: Actually to be a perfect mod you should also solder a flexible link between each point blade and its closure rail, as the Peco hinge loses electrical reliability after a while too...
 

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Hi Richard,

Not sure I fully understand how to do the mod on a N Gauge Point.

On the attached photo you will see that there is a fine wire on the underside of the point which connects the Frog to the Closure Rails.

Line Font Parallel Music Camera accessory

If I cut this the Closure rails can only draw current from the Blades when they contact the Stock Rails which would not be a very satisfactory situation. The two closure rails seem to be electrically connected together so cannot be connected to the stock rails as can apparently be done with the OO Gauge points.

Your help would be much appreciated.

Regards,

Trevor
 

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QUOTE (Expat @ 13 Jun 2008, 15:43) <{POST_SNAPBACK}>Hi Richard,

Not sure I fully understand how to do the mod on a N Gauge Point.

On the attached photo you will see that there is a fine wire on the underside of the point which connects the Frog to the Closure Rails.

View attachment 458

If I cut this the Closure rails can only draw current from the Blades when they contact the Stock Rails which would not be a very satisfactory situation. The two closure rails seem to be electrically connected together so cannot be connected to the stock rails as can apparently be done with the OO Gauge points.

Your help would be much appreciated.

Regards,

Trevor

***Hi Trevor.

Here is your drawing marked simply and an added line drawing.

I didn't mark on your drawing but if the wire you indicated as a bond IS a bond to the closure rails from the frog it should be cut - however I believe it is only a wire to the frog as the frog and closure rails are already one piece as they build it, and is merely the right place to atach the frog wire after the other mods are done.

As per the line drawing which I hope is clear you end up with 3 separate electrically bonded parts to the point.
(1) Left stock/closure/point blade
(2) right stock/closure/point blade
(3) frog

Richard
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[quote however I believe it is only a wire to the frog [/quote]
Hi Richard,

On closer examination I think you may be right. The fine wire connects the 'V' and the Frog and, in turn, the point blades themselves. i.e. the polarity of both point blade is set to the same as the frog. Cutting the rails as you suggest means that each point blade has a different polarity. All is now clear Richard. Thanks very much.

Incidentally, how do you recommend cutting the rails ? I suspect a Dremel + cutting disc might generate too much heat and end up melting the adjacent sleepers. On the other hand I'm concerned that using track shears might distort the rails.

Thanks again,

Trevor
 

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QUOTE (Expat @ 13 Jun 2008, 22:05) <{POST_SNAPBACK}>[quote however I believe it is only a wire to the frog
Hi Richard,

On closer examination I think you may be right. The fine wire connects the 'V' and the Frog and, in turn, the point blades themselves. i.e. the polarity of both point blade is set to the same as the frog. Cutting the rails as you suggest means that each point blade has a different polarity. All is now clear Richard. Thanks very much.

Incidentally, how do you recommend cutting the rails ? I suspect a Dremel + cutting disc might generate too much heat and end up melting the adjacent sleepers. On the other hand I'm concerned that using track shears might distort the rails.

Thanks again,

Trevor

Hi Trevor

a Dremel does it well - just be quick and precise. Better ina flexible shaft than diretly to the dremel.

Thats what I always use. try to find a small sized cutoff wheel though as there's not much space between the rails.

If U are worried about the dremel, a jewellers saw does it nicely.

Richard
DCCconcepts
 

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QUOTE there's not much space between the rails.

TELL ME ABOUT IT !!!

The Dremel with the flexi drive works fine as you say but I definitely need some smaller cutting wheels.

I now have one very sad looking point.

It's Ok though as I've been using it to practice soldering connections to anyway so it was already pretty battered.

Thanks again for your help,

Trevor
 

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Discussion Starter · #16 ·
Hi all

Sorry, I have had a busy few days since I wrote the original thread. Anyhow, thanks for all your replies. I have Fleischmann Piccolo (N gauge) with a Twin Center. I guess there are not going to be too many differences either by gauge or manufacturer. I have bought some electrofrog points and will study them and compare them to the insulfrog ones I already have. Then using your suggestions will hopefully minimise some potential problems.

BTW, can anyone recommend a good book on DCC? There seems to be quite a few but which one to buy?

The learning curve continues...

cheers
HM
 

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[quote BTW, can anyone recommend a good book on DCC? [/quote]

Hi Hawkmoth,

I bought "Aspects of Modelling - Digital Command Control" by Ian Morton and can thoroughly recommend it. It covers just about every aspect of DCC in language even I can understand and is very well illustrated. I bought mine from Amazon for £12.99.

Regards,

Expat.
 

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Richard,
Thanks for clearing the wiring up, two questions remain in my mind though are the two centre V rails to be insulated as per normal using the method you outline, also do i have to put a switch in to transfer power for the point depending on direction is this known as power routing ?
Sorry but i am electrically challenged you see .... lol

many thanks.
 

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The 'V' of the point as you call it needs to have the power switched either by the moving point rails which steer the train or if you have broken the connection from these to the 'V', the power is switched by an external switch which is "thrown" at the same time as the point blades.

If you want to see all this information in printed form, the current issue (13) of Hornby Magazine has a two page spread on live frog points. Available on an obscure bottom shelf at Smiffs now. (at least my branch of Smiffs had it on the bottom shelf slightly away from the other model railway mags. I had to hunt a bit to find it)

David
 

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After searching for some other stuff i have found a link with 'how to' type vids you all may find useful in some way, it seems the site is for handbuilt track but the principles are the same no matter. http://www.handlaidtrack.com/turnout-videos.php
I am contemplating using a jewellers saw now to cut the points after seeing the step 12 vid (lot neater cut line as the cut off disc is quiete wide when used in N gauge.
TREVOR many thanks for the reccomendation of the 'digtal command control Ian Morton ' book it really is invaluable information there.
 
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