Controlling polarity of Peco 75 turnouts

[NevinW]

My new layout is a shelf and I planned on no switch machines since it is completely a walkaround layout. I installed Peco 75 electrofrog turnouts and I am now finding out that electrical conductivity thru the points is an iffy thing. (on previous layouts I used switch machines and their extra points to control the frog, my staging area is wired this way). Of course is worked better before I added ballast and scenery but I was very careful to keep the ballast away from the points. I have cleaned the points but the reliability is still not there.

Short of rigging a lever through 2 inches of foam and plywood to an electrical switch below the layout, is there anything else I can do to improve the reliability of current flow through these switches. It looks like a jumper from the stock rail to the rail just beyond the points would work. What does everyone think? If I had to do over, I would have used non-routing turnouts (insulated frogs) since a DCC layout really doesn't need power routing turnouts. All this extra wiring really doesn't make sense on a walkaround shelf layout. Any other thoughts are greatly appreciated. Thanks - Nevin

[Anonymous]

I use peco code 75 turnouts and i find that the problem is usually glue form ballasting getting on the sides of the point and stock rails where they touch. The two little tabs on the bottom of the point rails are of limited use.

Get a bit of emery paper and fold it in half. Slip it in between the two rails where they touch and clean the gunk and oxidation off. There shouldn't be much of a problem of them getting dirty again.

Neil

PS. I just use the contact area of the points to control polarity. I have no other contacts and i find them perfectly reliable.

[BR60103]

The jumper won't work with electrofrog tirnouts. There will be a short circuit from south rail through jumper through frog through other jumper to north rail.

[NevinW]

After studying the recommendations on the Wiring for DCC website, it is apparent that the jumpers only work if you isolate the frog first, which must be done before the turnout is laid. I bought a few microswitches at Radio Shack last night and I an going to experiment with gluing Caboose Hobbies ground throws on them to see if I can come up with something for the really bad turnouts that don't respond to a good cleaning. I still think that commercial turnouts should be better designed to avoid these problems. - Nevin

[Anonymous]

QUOTE: Originally posted by NevinW


Short of rigging a lever through 2 inches of foam and plywood to an electrical switch below the layout, is there anything else I can do to improve the reliability of current flow through these switches.

This is not as hard as it might seem. Here is an easy way to make a linkage from the throwbar through 2 inches of foam and plywood to a microswitch under the table - and it can be done AFTER the turnout and ballast has been installed. Did this on Peco N scale turnouts when the points kept getting dirty and got tired of having to clean them, now i do it all the time when installing turnouts..

Evergreen Scale Models Strip Styrene 3/32" hollow tubing (#423) makes a nice bushing for 3/64" OD brass rod from a hardware or craft store. The brass rod is formed to pivot in this styrene busing so that only a single round hole is needed through the table. It is the need for only this single round hole that makes this method installable as an afterthought.

Drill a 7/64" hole (a 3/32" hole pinches the styrene tubing and binds the brass rod) through the styrofoam and plywood located between the first clear pair of ties from the thowbar (about 3/8" away in N scale) and the same distance from the rails as the hole in the end of the throwbar (add a hole in your throwbar if necessary) when the points are at mid-travel. Form the brass rod into a U shape with a short end that engages the hole in the throwbar and lets the rod slip down through the styrene tubing and out the bottom. Form the bottom of the brass rod where it exits the tubing to work a microswitch lever. Use glue to firmly fix the tubing into position so it can't move or bend and prevent the rod from rotating in the tubing. Place the microswitch as close as possible to the stryene tubing to minimize the required force yet still allow adjustment so the microswitch activates when the points are cenetered between the stock rails (to prevent electrical shorts).

Now thowing the points makes the brass rod rotate in the plastic bushing and transfers the force to the microswitch. This will work through many inches of styrofoam thickness, but eventually the torsion of the brass rod will be overcome by the force needed to operate the microswitch. In this case larger tubing and heavier rod will be needed.

Good luck with this.

[NevinW]

Thank you for the advice. I am going to try one this afternoon and see how it goes- Nevin