Okay, some of you guys must have done this. I’m looking to install a couple of insulated blocks on the new layout. Is there an easy way to make a contactor actuated by the weight of a passing train to move contact from one side of switch to another?
I guess I could try to find a couple of 153C’s, but seems like a fairly easy do-it-yourself project. Just remember, I am not an electrical engineer. Seems like some thin Masonite, or other nonconducting material, a coil spring, and some solder ought to do it.
Anybody got a noncopywrited plan from materials normally found at home to share?
Charlie, as a clarification as to what you want to do:
An insulated block would be a section of track of some length where you could shut off the power to that section (by using insulating pins on the center rail of each end of this section of track) using an on/off switch of some kind, usually called a single pole/single throw switch (SPST). This is useful for cutting off the power for one locomotive, while lets lay pulling another locomotive out of a siding.
An insulated rail (which I think is what you want to do) is a section of track that has one outside rail insulated (with tubular 0 or 027 track they make these kinds of sections) so that you can operate an crossing signal or something of the like. When the train passes over this section of track, the wheels of the train carry the current from the normal live rail to the opposite section of insulated rail which activates the accessory.
The contactor is a way of operating accessories without use of an insulated rail. The problem with the 153C is that your train needs to be of a uniform weight so that the heaviest car of the train (usually the loco) operates the 153C as well as the lightest car on the train.
MARX Trains at one time made an insulated “snap on rail” that went on top of a straight section of track, which would allow accessories like signals to be operated by the train. The thickness of these snap on rails will cause the train to bounce some, and they can only be used on straight sections. If you want one of these, The Train Tender sells them (well, if he still has them). He’s a parts guy who is highly recommended by me and also others on this forum.
I at one time, made my own by this method. I took a ordinary pie tin that had no perforations on the bottom, and cut a narrow straight section (about 1/4 in. wide by several inches long) of this. Then I “insulated” one side of this with electrical tape. I was
I suppose you could rig up a length of piano wire bent into shape in bellcrank fashion to a SPDT micro switch or snap switch located just off the roadbed and adjust the length of the arms to get the desired effect.
However you do it, I see the SPDT micro switch being part of it. For more operational options, you could use DPDT or other types of microswitches too.
Actually, I want the insulated block to run two trains simultaneously. I currently have three on my layout, but they simply run from the “hot” track to a toggle switch and back to the insolated block. this way I can have two or three trains on the track, but only run one at a time. Any combinatiion of my three interconnecting ovals can be hot a one time. I can jockey engines, uncouple cars, and recouple new combinations; each oval has an uncoupler.
I’m redoing my layout and want the SPST, or better - the 153C single pole double throw (to allow for the use of the block signals). For a first attempt, the SPST should be easier, and I don’t have the signals anyway.
The weight thing is a problem, as you mentioned. The contact must be made long enough for locomotive 2 to get off its insulated block. That could take two or three cars in a row on train one. I think I can arrange cars that way if the switch is sensitive enough without being too light.
One new thought. If the track were tilted, or listed, a bit just ahead of the contactor, that might give enough clearance to negate any kind of spring mechanism on the contactor - the track itself would become the spring. This might simplify the SPDT, too. Maybe if the pie tin were glued onto an emory board or something, that would give the needed strength.
I was answering Brianel 027 when you posted. For sure, the simplist way would be to get a couple of SPDT contactors. Do you know of any on the market, from say electrical contractors, that would work in place of the Lionel 153C?
If I can find an inexpensive ready-made I’m lazy enough to go that way. Just thought one could be built fairly easily.
An isolated control rail is, I think, by far the simplest and most reliable way to operate an accessory that requires a single normally-open (SPST) contact. It can also be used for an accessory like a block signal that requires transfer contacts (SPDT) with very little extra trouble (neither relay nor electronics).
I think I can get by without the isolated (outside rail) track. I talked to my son-in-law today & he has some micro switches he thinks will work. They are used to disengage the cruise control on a manual transmission vehicle as soon as the clutch is depressed a little. Not many manual trannies anymore, so he has some extra switches. I’ll check those out tomorrow.