Any prefference electro or uni for Peco frogs.

[Barnaby]

Now Rod that is a very good question.

I would think that if the points are hand driven then they can't possibly change the points over so I would expect a derailment to occur. That would seem to make the juicer somewhat irrelevant.

So if hand driven point work you will have to make certain the right road choice has been made or kerrr-boom derail occurs.

 

Best

[rodshaw]

Rather than have a derailment, I think I'd rather have a short circuit - easily corrected just by switching the points and pressing reset on the controller!

[south_tyne]

12 hours ago, kevinlms said:

Yes, but just in case you aren't aware, frog juicers can only be used on DCC.

 

Thanks Kevin. I know it is such a basic question but thanks very much for the clarification. It's useful to know!

[kevinlms]

17 hours ago, rodshaw said:

Presumably a frog juicer doesn't actually change the direction of the point? So you'll still get a derailment if you forget to do that.

Sorry I don't see the connection.

 

Changing the point direction is a different function to changing the electrical polarity.

 

Another way of stating it, is that a mechanical switch doesn't change the direction of the points either. What you want to achieve, is a method of changing the points AND switching the frog polarity at the same time, so that one or the other, doesn't get forgotten.

 

The prototype has a term for this, fail safe interlocking (on the mainline at least!).

[Barnaby]

I think you are missing the point here Kev, Rod is saying the same thing as I am also.

If the points are mechanically set via push rods but you fail to notice they are against an approaching train then you will get a short.

Even with a Frog juicer fitted that will try to swap the polarity over it can't change over mechanically driven points therefore you would get a derail as well.

 

Therefore I'm assuming that a frog juicer will only work with DCC controlled actuators unless...……………………..

we are to assume that a train approaching the Y end of a point would have its wheels push over the points to the right path as it passes.

That's not something I would like to plan for though.

 

As I mentioned in my opening post I've never used Frog juicers for all these doubts but if somebody can quote the definite operation of them I'll file it away in my ref folder for future use.

 

Best

[kevinlms]

2 hours ago, Barnaby said:

I think you are missing the point here Kev, Rod is saying the same thing as I am also.

If the points are mechanically set via push rods but you fail to notice they are against an approaching train then you will get a short.

Even with a Frog juicer fitted that will try to swap the polarity over it can't change over mechanically driven points therefore you would get a derail as well.

 

Therefore I'm assuming that a frog juicer will only work with DCC controlled actuators unless...……………………..

we are to assume that a train approaching the Y end of a point would have its wheels push over the points to the right path as it passes.

That's not something I would like to plan for though.

 

As I mentioned in my opening post I've never used Frog juicers for all these doubts but if somebody can quote the definite operation of them I'll file it away in my ref folder for future use.

 

Best

Sorry, I've read this through several times and really have no idea of what you're saying.

I understand what your saying about a loco, approaching a point being set up for the wrong direction (from the frog end of the point), but somehow, your expecting a frog juicer to change the point blades on its own?

 

If you don't want a derailment, then the point blades have to be set correctly, or you want power to switched off, to prevent the loco from incorrectly set blades.

Changing the polarity, by mechanical means or a frog juicer won't prevent a derailment.

 

 

[rodshaw]

One problem with Peco electrofrog is that they rely on contact between the switchblade and the stock rail for electrical continuity. I modified mine by cutting the rails to make a dead frog, and bonding each switchblade to its adjacent stock rail. Effectively, I converted them to unifrog design and achieved the polarity switch with under-baseboard microswitches manually actuated by the point rod.

As regards frog juicers, I only have six turnouts, one operator and one loco in operation at a time, and I'd rather have a short to cope with than a derailment if I forget to change the points. All I do if I get a short is set the points correctly and press a button on my DCC controller to reset it. But I can see how on a large layout, with more than one loco on the go and several operators, you don't want a short if you forget to change the points, as everything would stop and confusion would reign - so a frog juicer would come into its own there.

[Dungrange]

2 hours ago, kevinlms said:

Sorry, I've read this through several times and really have no idea of what you're saying.

I understand what your saying about a loco, approaching a point being set up for the wrong direction (from the frog end of the point), but somehow, your expecting a frog juicer to change the point blades on its own?

 

If you don't want a derailment, then the point blades have to be set correctly, or you want power to switched off, to prevent the loco from incorrectly set blades.

Changing the polarity, by mechanical means or a frog juicer won't prevent a derailment.

 

 

 

I think the point that is being made is that if the polarity of the frog is switched with with the point blades and the point blades are set correctly for the approaching train, then there should be no need for a frog juicer.  The electrical short that the frog juicer would correct for would be caused by the points being set incorrectly.  As such, what is the point of eliminating that electrical short at the frog and allowing the train to continue into the turnout if you are then going to derail the train?

[Junctionmad]

22 hours ago, Dungrange said:

 

I think the point that is being made is that if the polarity of the frog is switched with with the point blades and the point blades are set correctly for the approaching train, then there should be no need for a frog juicer.  The electrical short that the frog juicer would correct for would be caused by the points being set incorrectly.  As such, what is the point of eliminating that electrical short at the frog and allowing the train to continue into the turnout if you are then going to derail the train?

 

A frog juicer is simply a automatic replacement  for a mechanical switch or relay , switching the frog polarity. The quote above is very confused , if you switch the frog by a juicer , you don’t need another frog switch and vice versa. 

 

Its only used in situations where the frog polarity needs to be switched , it’s very handy in complex trackwork like double junctions ,scissors ,  slips and three ways , as to some extent , you can forget about complexity and just treat each frog on its own , this you can’t do woth microswitches and relays that are switched from the point position 

 

the good frog juicers , like the fully electronics tam valley ones , work , in my experience , absolutely faultlessly , zero issues. The only downside is cost 

 

With all DCC sound  locos , I MUCH prefer a protypical derailment , then a layout wide short, as restarting some sound equipped locos literally can take minutes.  So much so , that where, in the fiddle yard, , for economy reasons we switched the frogs, using the switch in the cobalt , we had to isolate the whole fiddle yards as incorrect points caused shorts rather then derailments and we are seriously considering retrofitting frog juicers. 

( our deltic has an engine start taking over a minute , and this is an exhibition layout ) 

 

my experience has been they remove considerable amounts wiring, confusion and ,complexity in complex track and “ they just work “  If you have the budget , they are the very best way to switch frogs 

 

 

juicers can  be used in auto  reversing loops and turntables also to automate polarity switching , they are useful in circumstances where mechanical switches arnt built in , to point motors , like using servo units , overall a great bit of kit. Wher  they cheaper,  they’d be everywhere imho.  While the technology could be deployed in DC , it’s much more complex and in DCC , most live frogs need external polarity switching , a case that’s not always true in DC 

 

dave 

Edited February 24, 2019 by Junctionmad

[Junctionmad]

By the way , to answer the OP original post 

 

a live frog point IS  ALWAYS better constructed electrically, by having each switch rail connected to its adjacent stock rail , and hence each switch rail isolated from its counterpart . By definition if you do that and wish to power the frog ( or more correctly the common crossing , and potentially some or part of the closure rails ) , then you must  switch the polarity of the frog by some external means. 

 

Hence electrofrog or unifrog, points constructed or modified to meet the best electrical arrangement , are in essence the same thing. 

 

Note that the timing of switching the frog doesn’t  have to be conincident with the switch blades movement  in a point constructed to the above citeria . It merely has to be switched in advance of a train bridging the switch rail to frog  electrical break point ( or in effect , simultaneously, as a frog juicer does )

 

hence frog switching could in theory be controlled by any number of methods , including track occupany, rfid , etc etc , however most are derived from point movement ( or the command to move points )  

[south_tyne]

I can appreciate people want to get things right and clarify the terminology but, reading some of the above, it is no wonder many people run scared when it comes to wiring up points correctly and sorting out polarity switching.

 

Oh for a rise in radio control......

[Junctionmad]

53 minutes ago, south_tyne said:

I can appreciate people want to get things right and clarify the terminology but, reading some of the above, it is no wonder many people run scared when it comes to wiring up points correctly and sorting out polarity switching.

 

Oh for a rise in radio control......

unfortunately , if you read through forums and other online stuff, you get a whole host of incomplete , incorrect or just plain mis-informed advice .  This tends to generate confusion as expertise is hard to determine on the internet and people who dont know tend to equate "good" advice and " bad " advice equally 

 

Theres nothing complicated in track wiring , either DC or DCC , nor is there anything complex in electro/uni frog or even converting PECO points to better electrical operation . it just that confusion has been allowed to gain ground over the simple realities 

 

If you have a live frog and you want to wire the point up in the electrically optimum way , you have to switch the polarity of the frog , you can do this in a number of ways .  If you dont wan to modify PECO electrofrog points , then you dont " need " to , they work as live frogs out of the box 

 

Uni-frogs are only different in that they work as Insulfrogs out of the box, if you want live frog , you must switch the frog polarity 

 

Thats it , theres nothing else , in situations where a electrofrog is modified , then its identical electrically to a switched polarity Uni-frog 

 

[Pete the Elaner]

On 23/02/2019 at 15:15, rodshaw said:

One problem with Peco electrofrog is that they rely on contact between the switchblade and the stock rail for electrical continuity. I modified mine by cutting the rails to make a dead frog, and bonding each switchblade to its adjacent stock rail. Effectively.

This is true for older points but Peco changed the design some time ago. I think they may still use the older design for 1 point because the tooling has not worn out yet.

 

More modern Electrofrog points have a cut-out in the webbing allowing the user to solder a wire between stock & switched rails. If you do this, you need to snip 2 small links from the switched rails to the crossing then power this by a switch.

They are supplied this way for those who want to buy a point & use it straight away. It would not be RTR is you had to fit a switch before it works.

[Dungrange]

19 hours ago, Junctionmad said:

A frog juicer is simply a automatic replacement  for a mechanical switch or relay , switching the frog polarity. The quote above is very confused , if you switch the frog by a juicer , you don’t need another frog switch and vice versa. 

...

where, in the fiddle yard, for economy reasons we switched the frogs, using the switch in the cobalt , we had to isolate the whole fiddle yards as incorrect points caused shorts rather then derailments and we are seriously considering retrofitting frog juicers. 

( our deltic has an engine start taking over a minute , and this is an exhibition layout ) 

 

Okay, just ignore my ignorance of frog juicers - I've never actually used one, so I'm a little hazy as to the wiring.

 

Regarding your comment on the use of Cobalts in a fiddle yard, that is my intended course of action on the layout I am planning.  I'm therefore interested in the reasons for your shorts.  Surely if all the frogs are insulated from the surrounding track-work, a short can only materialise from rolling stock bridging the gap between the frog and the 'wrong' running line, in which case you probably don't have sufficient clearance for a train to pass on the set route anyway.  I appreciate that sound locomotives take a while to start up, but the whole layout doesn't need to shut down if you've wired a number of power districts or sub-districts.

 

[south_tyne]

6 hours ago, Junctionmad said:

unfortunately , if you read through forums and other online stuff, you get a whole host of incomplete , incorrect or just plain mis-informed advice .  This tends to generate confusion as expertise is hard to determine on the internet and people who dont know tend to equate "good" advice and " bad " advice equally 

 

Theres nothing complicated in track wiring , either DC or DCC , nor is there anything complex in electro/uni frog or even converting PECO points to better electrical operation . it just that confusion has been allowed to gain ground over the simple realities 

 

If you have a live frog and you want to wire the point up in the electrically optimum way , you have to switch the polarity of the frog , you can do this in a number of ways .  If you dont wan to modify PECO electrofrog points , then you dont " need " to , they work as live frogs out of the box 

 

Uni-frogs are only different in that they work as Insulfrogs out of the box, if you want live frog , you must switch the frog polarity 

 

Thats it , theres nothing else , in situations where a electrofrog is modified , then its identical electrically to a switched polarity Uni-frog 

 

 

No I competely apppreciate that. I for one am glad that folk such as yourself are there to advise and give the right information. It does seem to be an issue that causes lots of confusion though. 

 

As with most things in life, if you follow the instructions then it is simple..... just three wires to deal with ultimately (if I have been doing things right all these years!)

[kevinlms]

11 hours ago, south_tyne said:

I can appreciate people want to get things right and clarify the terminology but, reading some of the above, it is no wonder many people run scared when it comes to wiring up points correctly and sorting out polarity switching.

 

Oh for a rise in radio control......

No that just brings in a different set of problems. Making room for the control gear, batteries, recharging circuits etc.

Is going clockwork any easier? Probably not as you need to reinvent something largely forgotten, space for springs, how to rewind. etc.

[south_tyne]

33 minutes ago, kevinlms said:

No that just brings in a different set of problems. Making room for the control gear, batteries, recharging circuits etc.

Is going clockwork any easier? Probably not as you need to reinvent something largely forgotten, space for springs, how to rewind. etc.

 

about such systems recently that I have found quite interesting but it's definitely not mainstream and probably never will be. 

 

Returning to the main issue though, from a complete lay-persons point of view, I see the gradual roll-out of unifrog across the Peco range as a good thing. It offers the best of both world, insulfrog straight from the box or electorfrog with modification and wiring. At the end of the day, you pays your money and takes your choice......

[Harlequin]

3 hours ago, south_tyne said:

 

unifrog across the Peco range as a good thing. It offers the best of both world, insulfrog straight from the box or electorfrog with modification and wiring. At the end of the day, you pays your money and takes your choice......

 

Agreed but just to clarify: <Pedant mode on> unifrog becomes electrofrog without modification, of course, just needs additional wiring (unless you want the point blades to also be switched electrically like electrofrog, which would be strange).

 

And just to clarify further: Unlike both insulfrog and electrofrog, unifrog performs no electrical switching at all - and that is also a Good Thing ™.

 

<Pedant mode off>

 

Edited February 25, 2019 by Harlequin

[The Stationmaster]

I have long had a preference for points with a live 'frog' (common crossing) as it offers some benefits such as continuous supply of track power to passing current collecting wheels and no need to provide separate isolation for any dead end sidings which the point leads to.

But there is also a disadvantage because unless the point has built in contacts (as per Peco's Electrofrog) you have to provide something to switch the polarity of the 'frog'.  And of course the reliability of Peco's built in contacts can become suspect due to dirt and mechanical failure.

 

So with Unifrog points I have no option but to provide the 'something' to switch the polarity of the 'frog' (plus another mod to make it perform exactly like an Electrofrog point and provide the dead end siding isolation as well.

[Pete the Elaner]

26 minutes ago, The Stationmaster said:

So with Unifrog points I have no option but to provide the 'something' to switch the polarity of the 'frog' (plus another mod to make it perform exactly like an Electrofrog point and provide the dead end siding isolation as well.

You do have a choice with switching the frogs. The dead part of the frogs are so small that many do not have to bother providing power to them at all. This requires no modification either. As long as you feed that wire to below the board, you can leave the switch for if & when it is required.

 

Using points for isolation can quickly get out of hand, especially when loops are involved. Isolating & re-feeding keeps things simple as layout design grows & eliminates the reliance on rail joiners for good electrical contact.

 

 

[Chamby]

My own experience with the unifrog, after an initial enthusiasm for the OO bullhead points, has been more disappointing.  There is a critical design difference compared to the electrofrog, in that the electrical break between the frog and switch blades are right at the frog throat, whereas the electrofrog has the breaks further down the switchblade.  

 

 

The consequence of this unifrog arrangement is that a short can occur when the back of a wheel momentarily touches the opposite polarity switch rail next to the frog, particularly when traversing the curved road.  This might be the reason why the OP’s 08 stutters on the point, rather than being due to a dead frog.

 

It is therefore more critical with unifrog points to ensure that wheel back-to-backs are correct, a common issue with some OO RTR stock.  Also, if you run locomotives with dual-pivot pony trucks, such as the Hornby L1, O1, P2 etc, a similar shorting will occur due to the unnatural angle of the pony truck on curves.  A third reason for shorting can be with long wheelbase locomotives, I have surprisingly experienced this with some Pacifics and Co-Co’s.  A click, spark and stall...  it is obvious when and where it happens, when you know where to look. 

 

I have recently decided to modify all my unifrog points by relocating the electrical break farther down the switch blade.  This is not an easy task when the track is already laid and ballasted, but it does cure the problem 100%.  Five done so far, another nine to go...  

 

My advice would be to steer clear of the unifrog if you are ambivalent about which track system to use.

Edited March 1, 2019 by Chamby
Clarification