Laying track, testing, and how do I address this?

Mark Truelove May 26, 2023

  1. Mark Truelove

    Mark Truelove TrainBoard Member

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    I wrote awhile back about laying an 8" radius track with flex track, to see what could negotiate it. I'm now working on the small layout that incorporates this in it.

    Not related to the 8", I've laid my main loop and some sidings and I'm testing with an assortment of locos, both DC and DCC.

    I have this one older DC loco (not sure what it is, that was a discussion awhile back also) that stutters/freezes on an insulfrog in one direction only. I don't understand how this can happen, electrically. It's the same wheels going over the same frog, the same distance from the wheels on the other end, yet it only happens when moving in one direction. The other way, it is dead smooth.

    Any ideas or suggestions? Have you seen this kind of behavior before?

    Thanks for your thoughts.
     
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  2. Hardcoaler

    Hardcoaler TrainBoard Member

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    I suspect that one side of the truck is somehow lifting off the rail. Run it through the switch and when it stalls, take a jewelers screwdriver and press down lightly on the side of the truck that's over the frog. If the locomotive comes alive, you'll then know it's losing contact and a deeper look might identify which axle. Trucks should be able to rock side to side a little bit, though I have some that do not do that.
     
  3. shider

    shider TrainBoard Member

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    Another possibility is that not all wheels are used to pick up power, either by design or fault. If it's a diesel, see if it will run with one or the other truck lifted. If it works with one and not the other, chances are that the truck isn't picking up power on both rails. If it's a steam loco, I've seen some designs where the drivers pick up on one side and the leading/trailing truck the other. (Not a great design, for sure.) This would cause asymmetric behavior over a short dead spot in the track.
     
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  4. BarstowRick

    BarstowRick TrainBoard Supporter

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    Okay guys! This is a very old problem with what sounds to be very old train equipment. As for me, it took a unreasonably long time to figure out what was going on. I played with the stalling locomotive and tried to add wires to the tenders wheels. As well as other nonsensical, nonproductive things.

    Once I got a hold of a Multi-meter and was able to test for conductivity and continuity... I then discovered the problem.

    In a nutshell. If you have a Insulfrog that simply means no power is present in the frog. Same thing can be said for any switch with a plastic frog. You can't feed power through plastic. Not going to happen.

    One of the reasons I made the change to Peco Electrofrog Switches and/or power routed switches.

    You can frustrate over this problem and blame the pick-up on the diseasel (sp intended) or locomotive. You can play with the switches and run wires all over the place add on a DPDT to reverse the frog. When you could simply switch over to Kato Switches, Peco Electrofrog and solve your problem.

    Something I've said and is worth repeating. Noting the radius of curves you are dealing with. Most N scale toy trains are made to run on 9 3/4" curves. Anything tighter and the trucks will fight it or simply leave the rails. "Wider curves are the best curves" other hobbyist and I have said.

    Just my two cents. Take it or leave it.
     
    Last edited: May 26, 2023
  5. Mark Truelove

    Mark Truelove TrainBoard Member

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    Awesome, great feedback. I happened to see a video today of someone having problems with an older engine on modern Peco points. In that case, the wheelset on the loco was slightly narrower than standard, and (long story: short) was causing the wheels to climb up on the frog as it passed. Also I've read about the larger flanges on older equipment that typically ran on less-proto rails. Running those flanges on modern rail can have similar effects.

    So, lots to think about and test. I'm not sure I know enough to successfully order more modern wheels for a loco, and I just need to pick and choose which ones I'll be continuing to run on the layout. We'll see...

    Thanks!
     
  6. Hardcoaler

    Hardcoaler TrainBoard Member

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    I'll bet you're correct. I read "insulfrog" and incorrectly thought it was a live frog.
     
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  7. Inkaneer

    Inkaneer TrainBoard Member

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    In all probability the wheel gauge was not the culprit. Rather the turnout was a Peco Code 80. I have commented on this several times on this forum about Peco Code 80 vs Peco Code 55 and do not want to do it all over. Do a search for Peco code 80. By the way, if you have a Peco Insulfrog turnout it is a code 80. If so, you should expect similar results as the video you watched.
     
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  8. BarstowRick

    BarstowRick TrainBoard Supporter

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    There are differences between the older or original Peco Switches and the newest ones.

    You'll get it figured out.
     
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  9. NtheBasement

    NtheBasement TrainBoard Member

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    What I found helpful: run it slow and take a video with your phone, first from one side then the other. Then run the video slowly on something with a decent sized screen. What I found was a wheel on the far (invisible) side left the rail long before it got to the turnout.
     
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  10. Mark Truelove

    Mark Truelove TrainBoard Member

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    Got it, thank you!
     
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