First, if you don't feel like you can tackle this project, we offer pre-built ones for you to order. $75 + shipping. The one you will receive will be like the one pictured below. The one in the write-up was my test door for the electronics so everything is in the open and more visible to show how to DIY.
Every morning as I lay in bed trying to sleep in but feeling guilty I'm leaving the chickens locked up in their coop I dreamed of a way to let them out where I wouldn't have to go outside, especially when it was cold out. Since at that time I had a nipple water system and a pvc pipe feeder I didn't have to feed or water them most mornings so it was just a matter of letting them out in the morning and locking them in at night. Not getting out of bed wasn't the only reason I wanted something. Some night we would stay out past sunset and I would've felt better if I knew they were safe in their coop. My husband thought about ways to run a string up to our house and through a window so we could open and close it from inside the house. We never tried that though. Instead I started looking up automatic doors for the coop. I couldn't believe the prices I saw. So I started searching for DIY options. I looked through a lot of examples. Some were beyond my skill level and the components needed cost nearly as much as a pre-made door. A lot of them were written in electrical schematics. Those meant nothing to me. I finally found a couple I liked. One was done by a guy here on BYC. I had a pretty difficult time getting things to work right following his directions. The way he wired his limit switches didn't work for me at all. And he drew it as a real schematic which isn't helpful enough for me. So here is my write up in as much plain english and simple drawings as I can.
Something to use as the door (I used a plastic cutting board)
rails for the door to slide in (I found some old drawer rails at a used building supply place - ReStore)
* a battery powered screwdriver (I found one at Harbor Freight and one at Walmart both around $9)
* I found a long screwdriver bit worked best for the cord to wrap onto
* cord to pull the door up (I used some paracord laying around)
* hose clamp to clamp the string to the bit
* wood for a frame (this could be optional depending on your setup)
* an electric timer
an on/off switch (optional but I found it helpful for testing and manual use of the door - walmart in the automotive section for a couple bucks or the same electronic source you get the other parts from - I have since taken this out of the design)
* a container of some sort to put the relay in to keep it away from dust and chickens
* 2 long arm limit switches (can be found at electronic stores or online for a couple dollars)
* 1 DPDT relay (double pole double throw - can also be found at an electronic store or online - I paid $4 for mine)
* wires - I had some laying around from a previous electronic project
* electrical tape
* wire connectors (the male/female kind that slip into each other, you need at least 4 of the female ends - can be found in the automotive wiring section of wal-mart or auto parts store)
* soldering iron - I have a cheap one (less than $20) and it gets the job done. Most of this job can be done with electrical tape but soldering onto the batteries and relay is really the best way.
* hot glue gun - optional. I used it to glue my relay down
Here's my simplistic version of how this works. The DPDT relay will switch the direction of the screwdriver each time it gets power. You hook up the power to a timer. When the timer is on the power comes from the wall and powers the screwdriver in one direction until a limit switch is activated. It stays like that until the timer turns off. Then the relay switches and the power now comes from the batteries and the motor again runs until the other limit switch is activated. If you don't have power to your coop, I've seen a solar panel put in it's place.
I like to see the final project before I begin working so things make sense, so here is the full thing laying on my floor.
First step is to do the hardware part. Attach the rails to the frame and insert the door. Make sure it slides smoothly. Line up and attach a limit switch to the top and bottom. Make sure the door activates them as it slides up and down. Remember that it will stop as soon as it hits the switch so place them appropriately.
Next you need to take apart the screwdriver. Some can have hidden screws under the stickers. Warning, only remove one of these screws. If you remove both of them then the motor can fall out and if you lose any bearings you're screwed (pardon the pun). My latest screwdriver did not have these screws. Luckily I was already aware of motors falling out so I was careful with it.
My suggestion is just take the cover off, don't pull anything out of the casing yet.
Now I think the wiring diagram will help so you can refer back to it as I detail the next steps (sorry I forgot to write "plug" on the box shaped icon). Please note the + and - on the motor are switched. Sorry, I didn't realize until I had already posted it and I don't want to redraw the whole thing.
Now look at your screwdriver innards; you will see the switch, control board, plug jack, motor and batteries. We won't need the switch since we will use our relay for that. So pull it up gently, just enough to reach the connections on it's board. You can cut that off at the board or desolder it if you can (leaves you more wire to work with).
I screwed a lid of a tupperware container to my board and then glued my relay to it (using a hot glue gun) so that I could cover it and keep it from the chickens and dust. I cut a section out where both pieces meet so the wires can go out. I also liked the relay glued down as it made soldering a lot easier. I have bought the pieces to do a second door for our other coop and this time bought an electrical box and cover from the hardware store for just over $1. The next door will be outside in the weather so I'll need to take more precautions with covering things. Feel free to use whatever container you have on hand.
Here are my relay switches
Most of the wires in the diagram should already be in place in the screwdriver. We just need to add our outside wires to the relay and switches. Here is how I did things.
- First I laid everything out so I could measure the wires. I wanted everything but the relay to go back inside the screwdriver.
- I used wire connectors to attach to the limit switches. Much easier than soldering or taping them on.
- Solder wires between the posts shown on the diagram on the relay. (the diagonal line and the line coming from the top left post)
- The positive wire of the motor and the black wires shown on the limit switches need to be connected together. I found it easiest to connect a wire to the wire on the motor since it was so short and then have the 3 wires connect in the middle of the board with a wire connector (the screw on type) which I then glued to the board so prying beaks couldn't mess with it.
- Wire the negative side of the motor to the relay.
- Pull the plug receptacle up enough to solder a wire onto the positive post. You can find the positive by looking at which one goes to the board, only one does, or using a multimeter to test the posts. Solder this wire to the relay (see diagram for position)
- Measure a wire from the relay to the battery negative terminal. Pull up the battery pack and solder the end of the wire to the negative terminal. Cut the wire just outside of the screwdriver body. Attach connectors (one male one female) at that cut and leave them disconnected. Solder the wire to the relay - top left post. Do not connect the wires yet. This will be the last step to make everything active and you don't want things running as you try to do the rest.
- connect the red wires of the limit switches to the appropriate places on the relay
- you should have the red wire that came off the switch that is connected to the batteries. connect a wire to this and attach to the appropriate place on the relay
- Connect a wire to the negative wire on the motor and the appropriate place on the relay
- attach your string to your screwdriver bit then take it out of the screwdriver for testing
Now for testing.
Test it WITHOUT the screwdriver bit in place because if it doesn't work you are going to jam it and could burn up your motor.
Plug in your last connection and the motor should start turning. Activate the limit switches. One of them should shut off the motor. Now either unplug or plug in the screwdriver (whichever isn't already done) and the motor should turn the other way and the other limit switch should stop it.
Notice which limit switch is activated with which power source because you'll set your timer accordingly.
If everything works you can disconnect the battery connector again so you don't have to worry about the motor while you get the screwdriver back together and mounted. Make sure everything is tucked neatly inside the screwdriver body with all the wires coming out where the switch used to be. Screw the body back together. Attach the screwdriver above your door. I used a strap and a screw through the bottom of the screwdriver. Do what works for your situation.
Here is a shot of my setup for the cord attachment. You can also see my on off switch that I have since taken out since it's just as easy to unplug/plug in the cord to test. I had the piece of wood there to keep the string from piling up on the screwdriver. I have since lost that piece of wood and haven't had a problem as long as I attach the string in the middle of the bit.
Good luck! This has been a lifesaver for me. I love being able to sleep in those extra 30 min with no guilt or stay out at dinner and not worry about them being safe in the coop.