# Making Track Sensors



## jjb727 (Apr 13, 2012)

Is there a way to make track sensors to trip certain actions to occur? I know there is one in model railroading where you use a motion sensor to activate crossing gates, but can we apply these to anything else? I want to make something that opens doors when the locomotive runs over a switch. I would say about 3 feet away to give the doors the time they need to open. So far I've come across two types of motion sensors, but I also thought that I could use a press switch that can be activated by the wheels of a train as the flanges run through it. Let me know if you like this idea...thanks!


----------



## Southern (Nov 17, 2008)

there are many ways to do what you want. Is this DC or DCC? 

There are a lot of block detectors out there that will work. You could put a micro switch under the track. If it is DC you could put a small piece of cooper sheet bent over one rail that the train wheels would push down and make contact with the rail.


----------



## jjb727 (Apr 13, 2012)

Southern said:


> there are many ways to do what you want. Is this DC or DCC?
> 
> There are a lot of block detectors out there that will work. You could put a micro switch under the track. If it is DC you could put a small piece of cooper sheet bent over one rail that the train wheels would push down and make contact with the rail.


I havent decided on the format yet (DC or DCC), so I want to stick with the theoretical for the moment. I want to make a switch that would open a door for the train to go through. It would work like a portal to another world (because my layout will not be realistic). So there will be two swiches, one outside and one inside (a building or a tunnel). One will open an entrance door and the other, an exit door.


----------



## Southern (Nov 17, 2008)

That is one of the great things about this hobby, It is your world and you can make the unreal, real.


----------



## gunrunnerjohn (Nov 10, 2010)

An inexpensive way to do this is with these circuit boards. They come with both IR sensors and reed switches for magnets. These guys also sell them in lots of 5 for a couple bucks less each.

Logic Delay Switches Circuit Board,Signal Controller,Lights on automatically x 2


----------



## ktcards (Sep 22, 2012)

gunrunnerjohn said:


> An inexpensive way to do this is with these circuit boards. They come with both IR sensors and reed switches for magnets. These guys also sell them in lots of 5 for a couple bucks less each.
> 
> That link was for a logic delay board that it used for trackside three light signals. When the train trips the sensor it changes the light to red, when the train leaves the sensor the light turns yellow and after a timed delay back to green.
> 
> ...


----------



## gunrunnerjohn (Nov 10, 2010)

I'm not seeing why this board won't do what he asked. 

Here's a board for crossing signals that can be switch triggered or linked to the previous board I posted.

Crossing signal control board


----------



## ktcards (Sep 22, 2012)

gunrunnerjohn said:


> I'm not seeing why this board won't do what he asked.
> 
> Here's a board for crossing signals that can be switch triggered or linked to the previous board I posted.
> 
> Crossing signal control board


It does, only it only controls the flashing, it doesn't turn it on and off. You can get the flasher circuits for as little as $4 each if you look around.

Ray


----------



## jjb727 (Apr 13, 2012)

gunrunnerjohn said:


> I'm not seeing why this board won't do what he asked.
> 
> Here's a board for crossing signals that can be switch triggered or linked to the previous board I posted.
> 
> Crossing signal control board


you're giving me good ideas, so its all good!


----------



## jjb727 (Apr 13, 2012)

Is there any way I can make a press switch for this to work? Like having a press switch?


----------



## gunrunnerjohn (Nov 10, 2010)

You mean a manual switch on a control panel?


----------



## jjb727 (Apr 13, 2012)

jjb727 said:


> Is there any way I can make a press switch for this to work? Like having a press switch?


not on a controller, but on the track to where the train's wheel's/flanges press it and a door about 2 or 3 feet ahead opens for it to pass through


----------



## gunrunnerjohn (Nov 10, 2010)

I'd be concerned about reliability with a track mounted contact, I'd a lot rather have optical sensing.


----------



## tankist (Jun 11, 2009)

Press switch? I guess you want momentary detection. The most reliable way is to use photo detection IMHO - train goes over a phototransistor located brtween rails and covers it from light. Do you plan on soldering something or buy ready product ?

If electronics are out of question you could use magnetic reed switch, you will need to install small magnet in your locos you want to be detectable


----------



## jjb727 (Apr 13, 2012)

gunrunnerjohn said:


> I'd be concerned about reliability with a track mounted contact, I'd a lot rather have optical sensing.


why do you say that?


----------



## jjb727 (Apr 13, 2012)

tankist said:


> Press switch? I guess you want momentary detection. The most reliable way is to use photo detection IMHO - train goes over a phototransistor located brtween rails and covers it from light. Do you plan on soldering something or buy ready product ?
> 
> If electronics are out of question you could use magnetic reed switch, you will need to install small magnet in your locos you want to be detectable


What you mentioned was an interesting idea! Thaniks! I was looking for something that would open the door for the train to go through (like a door on a building or a door to a "train base" sort of thing lol).


----------



## tankist (Jun 11, 2009)

jjb727 said:


> why do you say that?


models are very light. tripping a switch might not be possible and even if so there will always a possibility that it will derail a lighter car (hek, sometimes it takes nothing at all to derail ). so i'd keep it without any physical contact, either optical or magnetic. good luck


----------



## New Berlin RR (Feb 11, 2012)

tankist said:


> models are very light. tripping a switch might not be possible and even if so there will always a possibility that it will derail a lighter car (hek, sometimes it takes nothing at all to derail ). so i'd keep it without any physical contact, either optical or magnetic. good luck


or you could on the flip side trip the switch as the car is derailed from the switch coming back to the "at rest" position which wouldn't be fun at all...I agree tho its better to go with some type of optical type switch/trigger instead!


----------



## jjb727 (Apr 13, 2012)

tankist said:


> models are very light. tripping a switch might not be possible and even if so there will always a possibility that it will derail a lighter car (hek, sometimes it takes nothing at all to derail ). so i'd keep it without any physical contact, either optical or magnetic. good luck


Oh i see...Thanks for letting me know! I guess Ill go with the optical route. I hope its not hard to set up though :/ 

There needs to be more than one though, because there will be spots where I need the train to open a door from inside the buildings it goes through. I do not really plan on using a roundhouse, because it requires a massive amount of space that I don't have.


----------

