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Discussion Starter #1
Being new to this I'm unsure why somebody would use one of these instead of the other. I'm hoping there's a clear reason and not just personal preference. Surely there's situations that demand each.

Can someone explain it to me simply?
 

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Where rails cross each other, there has to be some electrical isolation/insulation.

Many commercial turnouts have plastic insulated frogs where the rails cross to insulate them.

Some turnouts (and especially any hand-built turnouts) have metal frogs, either a metal casting or fabricated from soldered-together rails when scratchbuilding/hand-laying a turnout. Since the frog still has to be isolated from the stock and point rails or everything will be dead-shorted, insulating gaps are cut around all sides of the frog.

At this point you have two choices - leave the frog "dead" and not add any additional wiring, but this has a potential disadvantage of having a short piece of dead rail and the possbility that a short wheel-base switcher could lose power and stall.

So you can add a wire to the frog and power it to eliminate the dead spot. However, you need to be able to "switch" the polarity of the frog power to match the rail(s) for the direction the switch is thrown. This can be done using auxiliary electrical contacts on the switch machine or control linkage or an electronic auto-reverser. AFAIK the auto-solution is designed specifically for DCC and I'm not sure that it will work on DC. Switching the frog power along with the turnout control/position can be done for any power system.

One disadvantage of a switched powered frog is that if an engine rolls into the frog from the "wrong" way it will cause an electrical short. With an auto-reversed frog (or an unpowered "dead" frog) the engine will keep going across the frog until it hits the points and may or may not successfully make it through without derailing, depending on the spring of the switch points and throw linkage and the weight of the engine. (Either way, operators kind of need to pay attention to running into turnouts lined against them...)
 

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The terms of ELECTROFROG and INSULFROG are used by Peco. However,
the electrical characteristics of these models are available in other brands, but
for simplicity I'll use the Peco terms in this post.

The reason some modellers choose ELECTROFROG turnouts is that they have short 4 wheel locos
or older locos that do not have all wheel power pickup. They lose electrical contact
on a nonpowered plastic frog. Most of today's locomotives have
all w\heel power pickup and have no need of the powered frog. The frog of an
Electrofrog changes phase or polarity when it moves. That would cause a short
circuit unless you install insulated joiners in both frog rails

In most cases the INSULFROG type orf turnout is going to be the best choice.

Don
 

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Discussion Starter #7
The reason I ask is that some of the turn outs that I bought from a friend were used on a DC layout 15 years ago, and have been in a box for 10 years. He sold them to me along with a lot of other track and trains. I've now been able to identify them as Atlas insulated frog turn outs.

This one in particular just yesterday started to misbehave by causing the train to stop on it. The controller beeps and then sometimes the train starts up again. Sometimes not. I took this picture hoping that someone can see something when it's enlarged that is the problem. The wires off to the side are not connected to anything and are not touching each other on the ends. They're only to move the switch anyway and as I understand it they're in no way connected to the rails.

547951


I was moments away from placing an order online for a bunch of replacements but decided to see if anyone here could identify the problem before I did. I'd rather not buy 8 turnouts today if I can avoid it.
 

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Discussion Starter #8
Here's what happens when the train rolls over it.

 

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I would look closely at the joiner on the left side, bottom rail in the photo. It looks like it’s only slightly making contact with the rail leading off to the left. I would try to center the joiner so it’s equally contacting both rails. It could be that it’s not currently making good contact and that’s causing a dead spot.

I don’t know what would be causing the beeping that you hear from the controller. Check what the manual says about that. For some systems, that means a short has been detected. Your turnout appears to have a wide gap between the rails that meet at the frog, so I’m doubtful you’re getting a short at that spot.
 

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Discussion Starter #10
Mark, that may have been it. I took the entire turnout off the table to look it over and then put it back, making sure that all the joiners were centered.

If that wasn't the problem then I changed something else without realizing it. That's how things get fixed sometimes I guess.

It's been running trains over it for a half hour just fine. Thanks!!
 

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From viewing the video in post 8 above...

Run the engine through the turnout again, same way.
Only this time when it stops, don't push against the engine.

Instead, put a little pressure against the switch points where they touch the outside rail (I think it's called the stock rail). Or, touch the shaft of a small screwdriver to both the stock rail closest to us (as we view the video) and the rail immediately behind the tender.

I'm wondering if (at least with that particular engine)
- the lead truck on the tender isn't picking up power as well as it should
and
- the trailing truck is picking up power, BUT, you have a "dead" or "flaky" section of rail between the switchpoint and the frog (as in "intermittent connection").

If you substitute A DIFFERENT left-hand turnout for the one we see in the video, do you still have exactly the same problem?
 

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i run small steamers , like a 0-4-0, on atlas custom line no.6 turnouts, and while i do have frogs that can be powered, i never did hook them up .... no need ??
 

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I've never done it, and I have a 0-4-0T and a GE 44 Tonner. No issues.
 

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The terms of ELECTROFROG and INSULFROG are used by Peco. However,
the electrical characteristics of these models are available in other brands, but
for simplicity I'll use the Peco terms in this post.

The reason some modellers choose ELECTROFROG turnouts is that they have short 4 wheel locos
or older locos that do not have all wheel power pickup. They lose electrical contact
on a nonpowered plastic frog. Most of today's locomotives have
all w\heel power pickup and have no need of the powered frog. The frog of an
Electrofrog changes phase or polarity when it moves. That would cause a short
circuit unless you install insulated joiners in both frog rails

In most cases the INSULFROG type orf turnout is going to be the best choice.

Don
How would you classify an Atlas snap switch? would it be an electro- type or an insul- type, or something else all together?
 

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How would you classify an Atlas snap switch? would it be an electro- type or an insul- type, or something else all together?
Atlas switches have insulated plastic frogs so it's similar to an "Insul-Frog".

"Electro-Frog" and "Insul-Frog" are brand/model names used specifically by PECO.

Electro-Frog has an all-metal frog and selectively "routes" power based on the switch points contacting the stock rails - so only one route beyond the switch will have power. The advantages and disadvantages of this are that you can kill or provide power to a spur simply by lining the turnout, however you're relying on the physical contact of the points to provide that power, and if there is any power feed from beyond the frog you have to gap/isolate the rails to prevent it from shorting out.

Insul-Frog has a plastic frog with jumper wires around the gap much like the Atlas switches.
 

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Atlas 'snap' switches have an insulated [read plastic] frog on them .... which are different than the Atlas Custom Line switches, which have a metal frog, that can be set either insulated [no power at the frog], or electrified [power at the frog]
 

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Thank you. My 2-axle engines pass across the Atlas snap switch frogs with no problem. So, when I expand my layout to include Peco insulfrong turnouts, the 2-axle engines "should" be okay with them?
 

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Most likely, yes. I'm glad to see that you'll be upgrading your turnouts. Atlas Snap Switches leave a lot to be desired in the quality department.
 
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