What does a frog juicer do that the contacts on a switch machine do not do?
Ed
depends on the contacts. I use ground throws that don’t have contacts except for unreliable ones on some.
Unless you have the “timing” perfect you can get a quick short if the switch machine contact makes before the point contact breaks.
If your points stick for whatever reason, you get a longer duration short.
I had that headache on a few power-routing turnouts. Since replaced with all-live turnout with a powered frog, some using the Tortoise contacts and others with Hex Frog Juicers.
The Frog Juicer switches phase as needed and detects the change faster than the DCC circuit breaker does.
Regards, Ed
With “DCC friendly” turnouts the frog should be isolated from the points and that wouldn’t be a problem.
I have seen examples of complex trackwork where a frog juicer was handy, and I can see the advantage with power routing turnouts if you don’t want to rely on the points for good electrical contact; however, with regular “DCC friendly” turnouts I don’t see any advantage to using it over switch machine contacts if available. In fact, I prefer the switch machine contacts because the frog juicer detects a problem and corrects it, while the switch machine contacts would prevent the problem from occuring.
Yeah, I can see that. So far, for ground throws I’ve used separate micro-switches. But: if ya don’t have reliable contact switching (or none at all), I can see using the thing.
Ed
And, Ed and Robert, I am getting the point about how one has to be careful about the switching and the timing thereof.
I will not be using switches that are the old style metal tie-bar (DCC un-friendly), so that’s taken care of.
Thanks guys for the explanation. So far, I don’t see the need IF the things you point out are dealt with.
Ed
Precicely why I went to all-live turnouts.
[all-live = DCC Friendly] I dislike all the conventions used to describe turnout functionality.
Peco throws even more confusion into the fray with Electro; Insul; and now Uni Frog [:S]
Scroll down to mid-page here: https://dccwiki.com/Turnout
IMG_8651_fix by Edmund, on Flickr
On the Shinohara power-routing turnout, top, if the bronze strip contacts the stock rail before any auxiliary switch opens (or “breaks”) you will get a short. In DCC this is enough to trip a breaker and stall operationns for agonizingly long seconds before resetting.
The “DCC Friendly” All Live turnout is below.
Cheers, Ed
This is a problem on DC layouts also, but frog juicers are not an option.
If the contacts on the switch machine MAKE before the switch points BREAK, you can have a circuit breaker open.
My solution was to use two rocker switches added to the Tortoise, because I exploit the power routing functions as much as possible.
-Kevin
Good workaround there, Kevin.
I know a modeler who opened up every Tortoise and cut the PC traces so that the wiper did not make contact until the very end of the actuator travel.
You can still use the internal DPDT for signaling.
Good Luck, Ed
Since I won’t be using switches with metal tie-bars, I don’t see this as a problem.
Ed
You still need a way to power the frog, even in DCC freindly turnouts. And even the old Shinohara turnouts can be made DCC friendly but juicers involve onyl running two wires to any power conection and of course the wire to the frog. Very simple.
To add even more, I cut an electrical instalation corner on one siding and shorted out the juicer (it was only a mono one) so fixed the short with a cut and a wire and the juicer still worked, how is that for engineering. A lot of technoligy today is overly complex and can allow you to do more than the average person needs. It is nice to have something simple that just works without dealing with a bunch of things.
Most switch machines have contacts for that purpose.
And they, too, need only three wires.
So why spend an additional $15?
Ed
You are asuming switch machines and even there you end up many times needing to add componints to make it work a hex costs $11 per turnout, singles are $2 more.
After years of scratchbuilding all rail turnouts I moved to the same opinion as Ed.
I use Atlas and newer all live, isolated frog Walthers turnouts.
I found them much more friendly to the features of my advanced DC cab control.
My mainline turnouts are Tortoise powered, and the Tortoise machines are controlled by relays that allow multi location pushbutton control. The relays and the switch machines provide plenty of contacts for powering frogs, providing power routing that does not rely on switch points, as well as input into the interlocking signal logic.
Manual turnouts use sub mini slide switches as the actual “ground throw”, also providing frog power and position feedback for power routing and signaling.
Even if I used DCC, I dislike the idea of the auto reverser or the frog juicer.
One day I will get the time and post the whole interlocking control wiring schematic and show how I get automatic train control protection, powerrouting, interlocking signals, and one button route selection with less wires than you think. And the only solid state device I use is Dallee inductive detectors.
If the turnouts and train permission are not correct, you have red signal, if you have red signal, the trackage past the signal is dead, your train stops…
Sheldon
Yes, I am assuming switch machines WITH contacts. Which is what I would buy.
Well, unless I can get one without and add the contacts for about the same price.
Then it’s a wash on cost.
So, like I say, why do I need to spend extra money and time on something that I don’t need? That’s why I asked the question, in case I’m missing something.
Now, I see that WITHOUT having contacts, the Juicer can make sense. And if you want to have the standard-ish Caboose ground throws up top, a Juicer underneath might be a good/great idea.
So far, since my ground throws are in an area that will not be scenery-ied, I have put in micro-switches at the other end of the throw bars. At about 35 cents each.
Let me note that I do NOT depend on points contact to power the frog. Or the points, for that matter.
Ed
Yeah there are a lot of solutions depending on what you run. I notice a lot of people make asumptions (me to at times) but the best solutions in model railroading depends a lot on what you use. I see this to the extreme in when people talk about radius of track.
No desire to use frog juicers. I use a different approach to power my frogs. I have a bipolar power supply buss. I run two wires to the turnout which has an isolated frog with hard wired points and closure rails (DCC Friendly).
The DPDT switch at the panel throws the motor direction on one side and the frog polarity on the other so only two wires run to the turnout - one to the motor and one to the frog. Very straight ahead an much less under the layout wiring at the switch machine.
BTW: auto reversers work great for turntables and reversing loops.
Guy
Why frog juicers?
Because, according to some folks (especially over on the “other” forum), if you don’t use frog juicers, along with decoders on your Tortoises (in other words, if you don’t spend north of $50 per turnout), you’re not a “real” model railroader.
(So I’m not a real model railroader. I don’t use frog juicers or stationary decoders at all, and Tortoises only where the turnout is hard to reach. In total, I spend less than $10 per turnout).
I guess I ran into the most “un-real” model railroader ever. He placed a slide switch on the edge of his layout, drilled a hole in the handle, and ran a rod through a brass tube over to throw the (track) switch. The slide switch had contacts, and he used those to feed his frog, etc.
Cheap as dirt, very reliable, didn’t show on the layout (so he could put scale switchstands out there).
VERY nice idea!
Ed