Model Railway Forum

Hi

If I had hair I would be pulling it out now, as I have a short on a newly installed double slip ( Insulfrog SL-90 type).

Confessions first....

- All my points are Insulfrog, but I have soldered feeds at the frogs and routed them thru my Cobalt point motors for frog polarity switching...... I guess this creates a hybrid which is halfway towards an electrofrog arrangement, but it works for me and cured some wide wheel shorting problems I had on old stock.

Following my trusted format, I installed a new double slip and have wired as per the attached image ( apologises for the roughness) , and fitted IRJ’s on ALL rails..... I have another fitted elsewhere on my layout and although it was sometime ago, I think I fitted it the same way and it has never caused me any problems.

This latest Slip shorts when the common wires are joined but operates perfectly if I remove everything but the two outer rail track feeds...... I have swapped around all the wires at the point motors, but no joy and it has me stumped.

I have checked my copy of Brian’s book and cannot see where I am adrift, but having spent hours on this it is possible that I now cannot see the wood for the trees...... any thoughts anybody ?........ should I have cut a link underneath prior to installation, but I thought that was only necessary on Electrfrogs and I have not done this on any other point ?????

I could of course leave it without any polarity switching but it would be par for the course for some loco to run foul once everything is ballasted in etc

Appreciate any guidance as I am out of ideas - thanks

Richard

The insulfrog slip does not require polarity switching as it is non isolating. By just feeding the outside rails all routes are powered with correct polarity.
Your wiring to the V rails will cause a short unless you remove all the links underneath and as the slip does not rely on switchblade contact there is no reason to do what you are doing.

Hi
Goingdownslow has given the correct advice. Do not use frog polarity switching, just allow the point itself to set the power routing

Thanks Guys - that advice makes sense but doesn’t this leave me open to shorts across the frog where the potential exists for the wheel to bridge the rails ?........ if I cut the links and add frog polarity, then a set of frog rails will be same polarity at any given time and as such no short due to wide wheels will be possible ?

Would rather lift it now and introduce a permanent fix than regret it later.

Thanks - Richard

Why not go the whole hog and convert them to live frog. I have done it with all my code 100 slips. Cut away the old plastic crossing nose.

If shorts are of a concern as you're already fitting IRJs on the ends of the Vee rails these will stop this.

Do not cut links or add frog feeding to the Insulated frog DS.
Just feed the outer pair of rails with the correct track polarity and it will work correctly.

File the V rails to make a new crossing nose.

Thanks guys for all the great advice - I will stick with the basic approach of simple feeds to the main rails and let the point switching take care of everything thereafter.

Thanks - Richard

Probably a bit late now (as usual) but if I might put an oar in here. My old layout included a number Peco Streamline code 100 double slips (dating from the 1970s) which caused countless problem where a wheel shorted across the Vee, effectively bridging between the running rails. (We're talking about Fleischmann and Liliput here.) To solve this I removed the parallel shunts between stock rails and frogs and wired the frog rails to the 3-4-5 terminals on the SM3 point motor. The frogs were thus correctly switched (but no less dead). Ironically, new single and double slips installed on the new part of the layout and provided with a simple power feed give no trouble whatever.

I like Goingdownslow's idea but doing the job in situ would be a nightmare and I don't fancy having to rip everything out (tracks, wires, motors, pushrods etc) to do the job on the bench. Is there not perhaps a supplier of replacement frogs in diecast metal or whatever out there, that you can set in after milling the plastic parts out? And where's Peco's Electrofrog code 100 double slip, by the way? Did they forget to set their alarm? I'd be grateful for any advice.

Cheers,
Artur

RSR Engineer wrote: ↑Fri Jan 08, 2021 5:34 pm And where's Peco's Electrofrog code 100 double slip, by the way?
Cheers,
Artur

I should imagine the Insulfrog and Electrofrog range will all become Unifrog when tooling is next updated.