Hey Everyone!
Elecrical work is my nemisis and thought I was pretty much done with it. But, in order to facilitate betteer operations at my turnouts I am replacing all pf my old Atlas ones with Fast track Turnout (#4). First one is done and in place and like the way practice trucks run through it. But in the process of wiring it, I am having fits.
Layout is operated by a Prodegy Advance system. I have Tortoise machines on all of the existing turnouts with the machines on a separate power source and each is wired through a DPDT toggle with power wires going to terminal one and eight on the Tortoise. No problems - switches switch and point rails move well and contact nicely. Have wires going from terminal two and three to the track power bus wires for layout. Terminal 4 is wired to the isolated frog.
Here is the problem: When turnout is thrown and point rails are set for the locomotive to run on the straight path through the turnout everything functions fine. But when I throw the toggle and point rails are now set to divert the loco through the turn I get a short as soon as the loco's wheels hit the frog.
When using an inexpensive buzzer attached to two aligator clips to test condictivity, everything works fine when point rails are set going straight. But when the switch it thrown to set the point rails to make the turn, no connectivity exists from the outside stock rail and the frog.
I have checked everything to make sure all PC board ties are gapped properly and switched wire leads 2 and 3 at the toritoise to see if that would make a difference. Nothing. I know that someone with a decent understanding of wiring could likely spot the issue in an instant. Sadly, I am NOT that guy - so I need help before I start breaking things.
Could it be that the internal part of the tortoise that is supposed to recognize the polarity change and switch the frog accordingly when the turnout is thrown may not be functioning any longer? The Tortoise is not new and has been on the layout for about ten years, but not hooked up to any frogs during that time. I have gone over everything with a fine toothed comb and see no issues, but things are not functioning properly and I am stumped!
Hopefully I have described the issue well enough that someone better at this stuff will immediately discern where the issue exists.
Thanks in advance, Dan
Fast Tracks turnouts are dead frog types. Did you cut gaps before and after the frog as shown on the template?
If those gaps are cut, the switch and point rails are completely isolated from each other. If there is no gap on the point rails you would have an immediate short. If there is no gap at the toe of the frog, there is the potential to short when one wheel crosses the gap in the point rails and another wheel is still in contact with the wing or point rail before the gap.
Also verify all the gaps were cut in the PCB ties. There are a few that are hard to see, such as at the frog.
If you have a continuity tester or an ohmmeter, verify the frog is completely isolated.
The tortoise has nothing to do with this, unless you wired its contacts to control the phase of the frog. If that is the case you may have miswired something.
betamaxThe tortoise has nothing to do with this, unless you wired its contacts to control the phase of the frog.
That's exactly what he said he did, but it sounds correct.
Henry
COB Potomac & Northern
Shenandoah Valley
You only need 3 terminals of the Tortoise to power the frog. 2 and 3 should go to your bus wires, and 4 to the frog. If you have the bus wires connected wrong to pins 2 and 3, you'd get a short regardless of the point position, so you would need to flip 2 and 3 around. Make sure 2 and 3 are connected to opposite bus lines - what you describe could happen is both 2 and 3 were connected to rail a instead of one to rail a and the other to rail b.
PCB ties can be tricky - even if it looks like you have a gap cut across the copper, because of the way they are cut with a shear, there could be slivers of copper on the cut edges making contact witht he solid copper on the back side, causing a sneak path. You need to use a meter in continuity mode and check on both sides of where a gap is supposed to be, any continuity at all where there should be a gap in the tie will cause a problem, and depending on where it is, it easily could be a short only for one direction. Compare the Fast Tracks diagram with where you have filed your gaps, and make sure they are all actually gaps - visual inspection is not enough, all it takes is a sliver of the copper.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks for the replies guys.
Yeah, gaps were cut at both ends of the frogs.
The two terminals (two and three) on the Tortoise are connected to bus rail wires.
As stated in original post, when the point rails are set to go straight then the straight section works fine, including frog. The curved rails work fine up to the frog. Throwing the point rail to go curved results in a total short.
Swapped the wires on the two Tortoise contacts (two and three) and the result was that when the point rails are set to go straight, there is a total short. When the point rails are set to go curved, the curved rails work fine up to the frogs. The straight rails work fine.
Went back and checked the gaps on the PC ties and have them everywhere they are supposed to be. Even went over each one again to make sure they were clear and not accidentally arcing somehow. Guess I will go through them again.
Will try the continuity test with a meter to see if I can find the culprit.
Since the problem flipped sides with the swapping of the Tortoise feeds, you have a short between one of the stock rails and the frog. Or possibly the points - did you cut a gap in the throwbar tie?
If it's now good when switch to the diverging route, but shorts when switched to the straight route, the short should be between the curved stock rail and the frog.
rrinker Since the problem flipped sides with the swapping of the Tortoise feeds, you have a short between one of the stock rails and the frog. Or possibly the points - did you cut a gap in the throwbar tie? If it's now good when switch to the diverging route, but shorts when switched to the straight route, the short should be between the curved stock rail and the frog. --Randy
Disconnect just the wire to the frog. Does it work now with a dead frog?
If you're not using the other SPDT side of the Tortoise, try they instead of 2-3-4.
It takes an iron man to play with a toy iron horse.
You can quickly test the turnout with the frog wire off as well. Clip one lead to one of the stock rails, the other to the frog. It should be open circuit, no continuity, no matter which way you move the points. Repeat with the other stock rail.
If one of them DOES show continuity, check every tie where both the stock rail and part of the frog inside the rail gaps are soldered to.
For reference, the 'other' contacts on the Tortoise would be 6 and 7 to the rail a and b bus wires, and 5 to the frog.
Unhooked the frog from Tortoise and tested. Regardless of which way the points are activated, there is no continuity between curved stock rail and frog. But, there is constant continuity between straight stock rail and frog. So the problem appears to be between the frog and the straight stock rail. Need to go through and check gaps and soldering until that continuity is eliminated - correct?
At this point, I am thinking that I should just pull this turnout and put it aside and build a new one and pay closer attention to continuity as I do. May be faster than trying to figure out where the issue is with this one. Then later, I can disect the offending turnout to find the issue, fix it, then use it somewhere else.
My money is on an incomplete or missing filed gap in one of the ties. Possibly creeping solder right under the frog that bridges one of those oh-so-critical gaps.
reasearchhoundBut, in order to facilitate betteer operations at my turnouts I am replacing all pf my old Atlas ones with Fast track Turnout (#4).
It doesn't relate to the electrical issues that you are seeing, but you might want to bear in mind that the Atlas “#4s" are actually about a #4½ frog: so they are a little less sharp than a “true” #4 such as Fast Tracks. So some longer or tighter equipment that negotiated the Atlas turnouts OK may not work over a “true” #4. Something to consider and perhaps test before you undertake a wholesale replacement.
Good luck with your layout.
Byron
Layout Design GalleryLayout Design Special Interest Group
selector My money is on an incomplete or missing filed gap in one of the ties. Possibly creeping solder right under the frog that bridges one of those oh-so-critical gaps.
cuyama It doesn't relate to the electrical issues that you are seeing, but you might want to bear in mind that the Atlas “#4s" are actually about a #4½ frog: so they are a little less sharp than a “true” #4 such as Fast Tracks. So some longer or tighter equipment that negotiated the Atlas turnouts OK may not work over a “true” #4. Something to consider and perhaps test before you undertake a wholesale replacement. Good luck with your layout. Byron
Thanks for the heads up.
My layout is pretty small so I don't run anything large through it. My biggest unit will likely be my Alco RSD 4/5, so thinking it should be okay.
If anyone suspects otherwise, throw me another heads up.
Can you post some clear close up pictures of the frog area to the side of the straight stock rail, like, showing the frog from rail gap to rail gap, and the ties and straight stock rail? There must be a missing gap or an incomplete gap in the ties.
I will try but at this point, I have virtually spent all day first trying different wiring configurations to see if it made a difference. Then pulled the turnout and checked continuity, rechecked a few gaps and actually thought I had it fixed. Put it back in and still have two PC ties giving me readings that power is going across. I have checked the gaps to see that I have them all and recut them so many times I think I am going crosseyed. About ready to yank out the two offending PCs, cut, gap, and put two new ones and see what happens. All the other PC ties are reading fine so don't know what gives with the two that aren't. They shouldn't be this twitchy and difficult to make function.
Thought perhaps there might be something under the turnout that might be causing issues but other than a little trace here and there of some ballast materials that is glued pretty solid to the homoisote, everything else is clean.
About ready to say **** it and give it a rest for a week.
If you are getting continuity across a place where you definitely filed a gap in the tie - I'm betting it's what I mentioned earlier - it's shorting around to the back side of the tie. Unfortunately the only wat to fix this is to pull the turnout and then cut a gap in the same tie but on the back side, so the copper is gapped on both sides.
This could be as simple as the solder for the stock rail going a bit over the edge of the tie, and same for the frog.
However, don't be fooled - if there is continuity across a very obvious gap, the continuity could be at another tie linking the frog to the stock rail. For example (not saying you did this, you indicate the rails are gapped as well), suppose you forgot to cut through one of the rails at the frog. Testing contiuity across the gap cut in one fo the frog ties, the current could pass all the way up the frog, the frog rail (where the gap should be) and then across at any of the ties that don't need gaps, then back down the stock rail. You can't pinpoint the faulty gap just by measuring across the gap in the tie. That gap may very well be perfectly fine. It's kind of like measuring an electronic component in circuit. If you remove the tie, you can test the gap, but unless you really were gentle and cut the barest minimum of gap in the tie, I'll be it's through. I tried my hand a fast Tracks a few years ago, I used a triangule file to cut the PC tie gaps, so the gap got slightly wider closest to the copper surface and what was deeper in was narrower.
My first turnout worked perfectly - I couldn't derail a truck even twisting it as it passed onto the frog. And that was the LAST good one I got, I couldn't get a good frog after that no matter what. And my point rails weren't great either, despite having both the point and frog jigs. Just not for me - and it seemed SO easy.
Thanks Randy. Took me a long time to finish my first turnout but the mechanical aspect of it turned out great. Hopefully I can repeat it, minus the electrical issues, on the rest. My next replacement turnout will be a curved one.
Are the rails cut (to isolate the frog) in the right location? Its easy to get it wrong and cause shorts. Ask me how I know.....
bad contact on tortoise?
greg - Philadelphia & Reading / Reading
So, posted about this problem some time ago and not wanting to be one of "those guys" who never shares about any resolution, I wanted to get back with an update. After driving myself crazy checking everything (so I thought) I could, I decided to build a new turnout to see what would happen. Did so and it worked perfectly in all aspects, mechanically and electrically. Then went and compared it carefully bit by bit to the old one and discovered that I had mistakenly cut the isolation gaps at one end of the frog one tie off from where they should have been (Wazzy, you were right). So, I filled the incorrect gaps, cut new ones where they should have been, and success! Everything now works like a charm.
Can't tell you all (but I suspect many of you know the feeling) how good it feels to have finally found the problem. Stupid mistake I know, and I can't figure out how I missed it all those times checking, but I did. Now I feel I can proceed with making more turnouts felling pretty confident I will at least avoid making that particular mistake again.
Thanks again to all of you that took the time to respond and try to help me out. I really, really appreciated it.
Dan
BTW - very impressed with the mechanical smoothness of the turnout. Hope I can achieve that with all of the rest that I'll be making.