Model Railway Forum

I am fitting two Peco electro frog points, SLE 88, on my DCC layout. As my points will be manually operated, I followed the u tube instructions, ie; snip the two wire contacts and solder two wires bridging the two outer rails on each side, as instructed. My diesel locos will run fine but my steam ones stall on the point. What is causing this problem and how can I fix it.

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What steam locos do you have Bryan.

If you snip the two links you effectively isolate the frog and you need to arrange a means of frog switching. Probably your diesels have pickups in both bogies thus they are spanning the frog picking up power on the powered rails before the frog and after it. The steam locos will only have pickups on the drive wheels and maybe not all of them hence the stall.

Without going into too much detail Brian has all the information about frog switching on his website.

Richard

HI Bryan - Have you left the spring in place? The moving rails need to make contact with the outer rails to get power. If your diesels have pick-ups at both ends, they will be picking up power even when one set of wheels is on the "dead section", as the diesel moves across the point, the front wheels will have moved off the dead section and be picking up power again. Brian asked what steam loco's do you have? If they are 0-6-0's it is possible that the short wheelbase is losing power on the moving rail sections. Some steam loco's do not have power pick-ups on every set of wheels (front bogie/rear pony truck). I have had the same problem - although my electrofrog points (with wire conversion and frog switching) are motorised, if the operating rod is not under enough tension, the moving rail will not quite make contact with the outer rails - I discovered this by a small loco stopping, and by pulling the tie bar the train moved on. Hope that is a clear explanation.
Barry

Richard (Tricky Dicky) has the problem correctly diagnosed. Cutting away the two link wires that bond each Closure rail to their Switch rails will leave a dead section after the closure rail gaps through the frog and out to the IRJs on the end of the Vee rails.
Either reinstate the two link wires across the gaps or fit some form of frog polarity switching to feed the frog rails. This can be an actual manually operated change over switch or a micro switch actuated by the points Tie Bar and fitted along side the point. Feed the switches Common terminal to the frog and each rail or DCC Bus wires via droppers to the outer tabs. Or some sort of DCC Frog Juicer.

You have had some good answers here explaining what the problem is. You now have to work out how to fix it. Unfortunately that's going to involve lifting the track and either rewiring or replacing the points. It's always worth taking some time to think through how points are wired before diving in with the snippers and following other people's examples of how to fix an issue that may not even be same issue that you have. In your case, if you have any more points to lay, think about using Peco Unifrog rather than Electrofrog. With these you won't need to do any wiring alterations and may even find that the tiny frog section doesn't cause any issues if left unpowered. You don't even need insulated rail joiners on the V with Unifrog points.

By snipping the wire links you have cut off power continuity to the frog and to the frog rails which form the V. You could simply reinstate the links and remove your added bonding to the stock rail and rely upon the physical contact of the switch blade to the stock rail. That would work (until the spring eventually starts to weaken and the contact goes) but isn't ideal. A better option might be to leave the switch rails as they are (isolated from the frog and bonded to the stock rails) but to insure that the frog and frog rails are linked and then drop a single wire from the underside of the frog. connect this wire to a SPDT changeover switch (with centre off position) with feeds from your left and right dcc signal to the other two terminals. Every time you manually throw the point you'll need to manually throw this switch too which is a bit tedious and easy to get out of sync and cause a short. That's about it for your manual control options without spending a bit of cash on an electronic solution.

Ok, so you could possibly use a frog juicer to switch the polarity of your dropper which feeds the frog. BUT first you'd need to check that your dcc controller is compatible with using these devices. Personally I don't like frog juicers because they work by allowing a momentary short circuit to sense when the polarity needs to switched. This could cause transient voltages (spikes) on your dcc signal which may lead to other problems. As I said, not my choice but plenty of people use them.

My preferred solution to this would be to use a Cobalt IP Digital point motor which solves everything. Reinstate the link wires and remove the bonding wires between the switch blades snd stock rails; wire a dropper from the under side of the link wires and remove the spring from the point. Fit the point motor as per the instructions and connect to your dcc bus. Connect the frog wire to the S1 Frog terminal. If you don't want to control the motor from your dcc control system you can simply wire a couple of basic pushbutton switches to the PBS terminals and you have manual control. You can mount the pushbuttons close to the point or wire back to a control panel as you wish. Just press a button to activate the point and the frog polarity will automatically change over at the mid point of travel avoiding any short circuits.

Good luck and let us know how you get on.

As has been described above, the problem is that you have only gone halfway in the process of modifying the electrofrog point to improve its performance. If, as you have done, you cut the links then an alternative way of supplying power of the correct polarity to the frog is required.

The simple and cost effective solution for a DCC layout is to fit a frog juicer. Many types are available but the simplest and cheapest in my opinion is the Gaugemaster Autofrog which only requires three connections - one to the frog wire and the other two to each of the stock rails. I use them on each of my layouts - they perform perfectly every time and are very much ‘fit and forget’.

Many thanks guys for all your replies. I have reverted my two points to "factory settings" and every loco runs fine over the points. I have a total of 163 manual points on my layout, which is 12ftx40ft. To fit point motors would require a mortgage, not to mention the wiring mine field. My points are a mixture of Hornby, Bachmann, Peco insul frog and recently Peco electro frog. They all get a good cleaning every three months with white spirits, they all run fine. Some points are 22 years old. The "hand of God" does not bother me, as I like to run up and down the layout, checking track and setting out routes. Once again many thanks for your replies.

Points used to be easy things Bryan. I’m with you, handraulically operated points are fine for me.