How I made my dumb locks a little smarter!

Hi all :wave:

Just wanted to share my take on the idea, this is such an awesome idea! :dizzy:

First I took my Xiaomi door sensor and soldered on the contacts.

Then I soldered the ends of the wire on to two battery springs which are glued on to a piece of cardboard. Also had to glue a piece of tinfoil of the deadbolt to make the contacts trigger.

Ran the wires and stuffed the board back into it’s case.

NOTE :warning: My sensor was being really unresponsive/reporting the wrong state at first. I had to try all sorts of position for my sensor, and finally found a spot where it works.

Now it works! Huge thanks to everyone for sharing the idea :heart: !

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I did very similar using the Xiaomi door sensor, easy to solder across the reed switch and add your own contacts.

In one case there was no bolt that moved when locking the door so I added a DIY actuator made from a bent nail.

I used a microswitch rather than making my own switch. They are long term v reliable if you can mount them securely.

The other thing that worked well was buying some pre-wired micro jst connector pairs:

image https://thesaberarmory.com/wp-content/uploads/2017/12/MICRO-JST-2.jpg

Very cheap and makes the installation much easier.

Hi Dave,

Can you provide some more photos in situ, showing how the nail hits the switch please?

John

First post so hello everyone and thank you for all the inspiration and knowledge I found here!

Here’s how I made my dumb lock smart.
Step 1 - I placed Fibaro Door/Window sensor inside the cavity in the door frame.
Step 2 - Using two-sided tape I sticked small neodymium magnet to the bolt.

The sensor is battery powered so I didn’t have to do any wiring.

I had to remove the cover of the sensor because otherwise it wouldn’t get through the clearance. That 1 mm made a difference :slight_smile: I also needed to pad the sensor with foam so that it’s closer to the bolt. Otherwise it wouldn’t trigger the sensor.

It was a bit tricky to align the sensor with the magnet on the bolt. To make it easy I glued two even smaller magnets (1 x 4 mm) on the other side of the foam. Those magnets are weak so they don’t trigger the sensor but they are strong enough to stick to the metal inside the lock cavity. This allows me to secure the sensor in position aligned with the bolt. It will also make it easy to remove the sensor for battery change.

It’s been only 1 day since I got this working so I’m not sure if the double-sided tape will reliably hold the magnet on the bolt. I might have to glue it later.

The magnet on the bolt is N38 neodymium 1 mm thick, 10 mm in diameter. Supposedly it pulls 0,5kg but I never checked. It triggers the sensor reliably.

Sensor https://www.fibaro.com/en/products/door-window-sensor/

Pics:

What a great idea!

I’ve left our back door unlocked a few times, which has earned me some stern looks from my wife. She asked if I couldn’t find a way to detect it, which led me here.

After considering a microswitch or magnet, I ended up going with two battery springs - after cleaning the end of the bolt it worked first time. The Aqara sensor was a little fiddly to get into, but no real issues.



I have a rule running in NodeRed to warn me in the evening, if the door is closed but left unlocked for 30 minutes - it sends me a persistent sticky notification so I see it until the door gets locked, which should do the trick :slight_smile:

Hi Dave, could you show us how the nail activates the switch? My door is like yours where turning the key cyclometer doesn’t throw out any bolts, it just locks the already thrown bolts into position.

Kind of difficult to get a good photo. Essentially I glued a flat plate of plastic to the arm of the switch, then mounted the switch to the inside of the door strike plate with a drilled hole showing through for the nail to hit.

You can see a small mark where the nail touches on the white plastic.

The contact area needs to be quite big compared with the nail because the range of movement is quite big with seasonal/temperature variations.

I also removed the head of the nail to remove the possibility of it getting caught on the strike plate.

Thanks buddy. Just finished mine today. Similar method to you in the end. Fitted a micro switch in the door jam that gets triggered by an actuator on the lock side.

Hi @Nuuki ,

I have a rule running in NodeRed to warn me in the evening, if the door is closed but left unlocked for 30 minutes - it sends me a persistent sticky notification so I see it until the door gets locked, which should do the trick :slight_smile:

Super interesting, I’d like to do the same ! Would you mind sharing the related node-red flow please ?
I don’t know nodered (yet), and I thought this usecase would be the occasion to learn !

Thanks a lot !

To anyone who’s been using a microswitch of sorts for a while now: How’s it holding up? Seems like it’s probably the best option in terms of non smart lock approach but I do wonder how long before the buttons give up.

@edelans @Nuuki
I would love to see that nodered script to.

Hey @Nuuki - mind sharing a close up of the wiring you did with the Aqara Door Sensor ? I’m no electronics expert, so I have no idea which spots I should soldier wires to (BTW - how did you figure this out yourself ?)

That’s pretty easy - you can either replace or keep the reed switch in place, but you just solder one wire each to either end of the switch (see the red circles):

As you can see from their photo, @Nuuki drilled a small hole through the casing of the sensor; you will have to do the same, otherwise you can clip the pieces back together.