Fixing the hole between the frog and frog rails

[joelm]

Hey all:  I'm using Peco code 80 electro-frog turnouts and find that the wheels on the frog side of the truck drop down into the space between the end of the frog and the start of the frog rails. The flange hits the bottom and then the wheel pops/rolls back onto the top of the rail. This action sometimes causes derailments, and has kept me from running steam, because the pilots almost always seem to pop up enough to derail. 

Using wide metal wheels on the rolling stock seems to have helped a bit in reducing derailments (not quite sure how, but I'll take it.) 

The obvious fix is to fill the space with styrene to the height of the flange, so the wheel rolls right through on the flange. (Any suggestions on the thickness?)

I'm wondering if anyone has tried this fix or anything else to address this.  If so, would you please share what you have done? Thanks.  Joel 

[wazzou]

I've done just as you described on an older, now gone layout.  I used .010 x .040 I think in both the bottom and inside of the frog and then filed the ends to a point.
Just experiment a little, it will become obvious what lengths you'll require as you do more.

[peteski]

Peco (and other European) track are designed for the giant (larger than the pizza-cutter MTL wheels) flanges of the European N scale models.  The solution you proposed should take care of the problem. I proposed doing the same on friend's layout (which uses Peco track) after we noticed the same problem with the Kato FEF-3 loco (which has very small flanges). But until my friend upgrades all his boxcars eliminating the pizza-cutter wheels, we have to hold off on this modification.

[Dirk Jan Blikkendaal]

4 suggestions/remarks:

1. I had the same problem on some old Peco turnouts (in those days there were only wide threads and deep flanges. turnouts - also Peco - have since then been redesigned  to accommodate small flanges).
as far as I could dtermine it was not the dropping auction that caused the derailment but picking the point due to larger tolerances on these old turnouts.
2. if it's an old(er) turnout ad a shim .010 x .040 to the inside of the guardrail opposite the frog (full length of guardrail, no need to file anything because the guardrail is bent backwards at both ends, paint and it's almost invisible). if your wheels (small en deep flanges)are correctly gauged it will prevent them from picking the point. I did this with some Pecos located in an old (40 year) Ntrak module which I operate every now and that solved the problem.
3. check the gauge of the pilot truck (maybe you have done this already and then please ignore). I often find wheelsets even on new locomotives (diesel and steam) are not correctly gauged.
4. pilot trucks are often very (or too) light. on some pilot trucks I have glued 1 or 2 small pieces of leadsheet between the wheels, hardly visible or not even visible.

for what it's worth.... good luck, Dirk Blikkendaal

 
 

[Greg Elmassian]

If you are using a powered frog, and force the wheel to ride on the flange, instead of the rail heads, then some of your power pickup will be from the flange.

If this is true, you want to shim the frog with something conductive, not an insulator.

Also, by concentrating the weight on the relatively sharp flange, styrene would wear much more quickly than metal.

A way to get a brass shim in the frog would be my choice, and some way to ensure electrical conductivity between the shim and the frog.

Greg

[joelm]

Thanks guys for the quick and thoughtful responses.

* I am using older Peco electro frog turnouts, at least 20 years old, for the most part.
* Shimming the guard rail is SOP on the railroad; so the derailing is not from picking the frog.
* Power pick up isn't an issue, all the frogs have Frog Juicers and the point rails are jumpered (also SOP on Pecos), so while I agree that styrene might wear quickly, I'm concerned that using brass might create electrical issues. I'll have to think about that.....
* I will check the gauge on the pilot trucks; I hadn't done that yet. But it's also an issue with any car - they all bounce, but 95% don't derail.
* I think .010 styrene or brass sheet will work, so that's what I will try.

Joel

[peteski]

I think that unless this is a display layout operating 8 hours per day, 7 days week, plastic shim will be durable enough not to wear out for years (or for the life of the layout). we are talking about lightweight N scale trains here (not some large scale heavy models).

As far as meta shim goes, I'm not sure why you think that would cause electrical problems. The rails surrounding the shim on the bottom of the frog will all be at the same polarity.  If you want the shim to provide electrical path to the flange then it has to be somehow reliably connected to the surrounding rails.

[Santa Fe Guy]

We had a similar issue on all of our Melb N Trak modules fitted with Peco turnouts as did several members on their home layouts and installed styrene as suggested, problem solved.
Many hours of running and no issues with wear.
Rod.

[Curtis Kyger]

I've never had the styrene shims wear out; but I have had them come unglued.  I originally tried super glue; then tried epoxy; and found my best result with good ole' Walthers Goo.

[Greg Elmassian]

yes I stated about the electrical connection between the shim and the frog in my post.

when you ride on the flange, it lifts the tread from the rail head (the whole goal of this exercise) or at the very best it worsens the electrical contact.

Contact between the sides of the flange and the frog will be minimal.

Now you might not NEED any conductivity through the frog, but I made the assumption that the purchase and use of the electrofrog was for reasons of power pickup through the frog.

Greg

I think that unless this is a display layout operating 8 hours per day, 7 days week, plastic shim will be durable enough not to wear out for years (or for the life of the layout). we are talking about lightweight N scale trains here (not some large scale heavy models).

As far as meta shim goes, I'm not sure why you think that would cause electrical problems. The rails surrounding the shim on the bottom of the frog will all be at the same polarity.  If you want the shim to provide electrical path to the flange then it has to be somehow reliably connected to the surrounding rails.

[peteski]

yes I stated about the electrical connection between the shim and the frog in my post.

when you ride on the flange, it lifts the tread from the rail head (the whole goal of this exercise) or at the very best it worsens the electrical contact.

Contact between the sides of the flange and the frog will be minimal.

Now you might not NEED any conductivity through the frog, but I made the assumption that the purchase and use of the electrofrog was for reasons of power pickup through the frog.

Greg

Peco frogs have (as we already know) deep frogs and also wide flangeways.  That is why modern narrow-tread and low flange wheels fall into the the frog because the wheel tread is too narrow to span the rails across the flangeway. If there is some styrene strip installed in the flangeway to reduce its depth (assuming that it still results in a flangeway slightly deeper than the size of the wheel's flange) then that will not affect the tread's contact with the metal railhead.  However that type of a fix will greatly reduce the wheel dive when it corsses the flangeway of the frog.

[nkalanaga]

Given the width of the flangeway, once you have shimmed the guard rails to keep from picking the frog, you can also shim the frog flangeways the same way.  Use your NMRA gauge to see what shim you need, then glue it to the wing rails.  Once you have the flangeways correct on both the outside rails and the frog, the wheels shouldn't drop, regardless of the depth of the flanges.

Cut the shims a little long, let them stick out into the opposing flangeway, then trim them to fit.  In effect, you wing rails will now be thicker, but the flangeways will still have neat corners, and won't catch the flanges.

[joelm]

NKalanaga: Hadn't thought to shim the frog flangeways. Have you done this successfully? (I'm concerned that the narrower flange way at the frog would result in picking of the frog.)

Santa Fe Guy: Did you use .010 in bottom of the turnout?


Thanks guys. 

[wazzou]

In my first response, I mentioned that it is helpful to raise the frog level and shim the inside as well.  .010 x .040 Evergreen strip.

[Greg Elmassian]

If your wheels are gauged properly, and your flange is not too thick (not tall, thick) then you should not pick the frog.

This is clearly dependent on the flangeway widths being in NMRA spec. Both have to work together.

Greg