I have a number of Insulfrog HO track switches, code 100, on my layout. I file down the Code 100 Peco rail to mate with Atlas Code 83 track.
I’ve installed sound in most of my locos and I have noted that nearly all of them “click” and restart the sound sequence when crossing over a section where I have two switches mounted frog to frog. I have tried everything I could think of. Added new power “drops,” added and removed insulating gaps; nothing made any difference.
Recently, I decided to find the cause. So I took the advice of the local hobby shop and placed a loco on the track but not addressed. Pushing it by hand through the section I was able to see a spark as the first set of wheels crossed the frog. Thinking that the insulation at the frog would protect against that, I was surprised. So I borrowed a little of my wife’s clear nail polish and painted both frog rails for about 3/8". Voila, no more spark; no more sound resetting; no more erratic operation!
I suspect that adding some shims to the guardrail opposite the frog to narrow the space to something closer to NMRA specs might accompli***he same thing but the clear nail polish is a lot easier. Just have to remember not to clean that part of the switch though I am not sure the usual rail cleaners would remove the nail polish.
When I think of all that I’ve done to resolve this problem, I’d like to kick myself for not trying the obvious.
What you describe here is the drawback to Insulfrogs…Not every layout has this problem, but when it comes up you will happy to know that the reccommended fix is exactly what you did. You will most likely have to re-apply the nail polish as it wears off from use.
When mating code 100 to code 83 at turnouts, I have been told to add some shims under the code 83 to align the rail connectors evenly.
The spark you are witnessing will cause a spike of voltage that will act to reset the sound sequence. If you had an oscilloscope, you could actually witness this “spike” on the rail being picked up by sound board.
I’ve had this problem in my staging yard since I use Peco insulfrogs because they are otherwise nice DCC friendly turnouts.
Notice how insulfrog turnouts are constructed in this closeup photo:
The inside “toe” of the frog is plastic and it separates the two diverging inside rails. Those two rails are opposite polarity and if a wheel tread happens to bridge that small space, you get a short. Unfortunately, shorts are not uncommon at this location on an insulfrog turnout.
(click to enlarge)
To solve this problem, I use a motor tool with a cutoff disk to cut a gap through the rails centered on the tie just past the end of the frog wing rails. Cut all the way through the tie as well so that you cut the jumper wires under the frog that power these rails, to insure that the metal railheads inside the frog toe area go dead. Superglue some styrene into this gap (and trim to the shape of the rail with a fresh xacto knife blade) to make sure the gap never accidentally closes and to add some structural strength back to this toe area now that you have cut the gaps.
You will need to run feeders to the two inside rails past the gap since they will now be dead as well, but it’s a small price to pay to permanently eliminate the short problem with these turnouts.
If your track is not laid, you can get the same effect by putting insulated rail joiners just beyond the switch. I make this standard on my switches, both electrofrog and insulfrog.
Also look at your wheels. They may be wider than standard.
This is definite design flaw with these Peco turnouts. If you use plastic wheels it’s not a problem, but I use metal wheels. The problem occurs with about 50% of mine. I use the paint approach for insulation. It’s a quick fix. You just have to be careful when cleaning the rails that you do not remove the paint.
The proper way to attach rail of one code to rail of another is to notch out a piece of the head and neck of the larger code, then file the base until it slides flat under the smaller code, then solder the two together. If done correctly, a thumbnail will not pick up any “click” when passed over either the top of the joint or the inside railhead. A slightly thicker tie may be needed for the first tie under the smaller code section, to support the transition…
Thanks for the tips re: frog shorts. I was just browsing the messages and this is a problem that I have also.
Looks like I had better check this message board more often.
Just starting back in after many years away from working on my trains.
happy railroading to all.
The Hoot
I have found that a piece of styrene rod filed or cut to fit and about 1/32 or so of an inch long works great. I’ve done it to several Peco Insulfrog turnouts and no more bridging!
Using a photo like Joe Fugate did, could someone show where to put the nail polish on the rail? I use all Insulfrogs but the rest of my track is also code 100. Should I go ahead and use the nail poli***rick anyway or just if a shorting problem occurs? Thanks.
We have nearly 20 Peco Insulfrog turnouts on our HO scale club’s layout and have never had an electrical shorting problem with a single one. When they were installed, I put insulated rail joiners at the ends of both rails that diverge from the frog.
To answer where to put the nail polish, refer to Joe Fugate’s picture of the Peco frog. Paint the area from the tip of the frog to where he shows cutting through the rail. With the nail enamel trick, you have to remember NOT to clean that part of the switch. Howevr, it can be repainted in approximately 3 to 5 seconds.
I have 60 Peco insulfrog T/O on my layout. The bulk of them are small sized. 8 or 10 are med and about 10 or so are large size. The large are used on the double main. I too have found problems with shorting. For some reason I very seldom have a prob with the small or med. 99% of the time it is on the large T/O. The two rails in ? are so close. My steam engines have the most problems almost everytime particularly on crossovers. My diesels sometimes. So I keep “borrowing” the wifes clear nail polish and that seems to work until I wear it off with cleaning. I really don’t want to cut the T/O’s but on the other hand it is a PITB putting on the nail polish. Are these two solutions the only solutions?
Terry
Refer to the top picture on jfugate’s post. The styrene should go between the rails just before (or after, depending on how you look at it) the insulated point. If you look at the second photo, about where it says “Cut gap” is where the styrene should go. If I get time, I can go out to the layout and take a good pic to post.
