Motorized Door Lock

by IamTeknik Sep 16, 2014
Download All Files

Thing Apps Enabled

Please Login to Comment

maybe someone can redo my design (i made it a few years ago and never posted it.
i wanted this to be more secure and also wanted to be able to lock my door from anywhere so instead of using the plastic dead bolt i opted to use a regular dead bolt.

i elongated the gear rack and made teeth on the bottom as well as the front, i then made a gear that encased my dead bolt switch so when the servo moved the gear rack it turned the gear on the dead bolt.

can u make part for 9gr servos :S

Awesome! Made two of these. I bought servo motors online just for this, but while they where on their way in the mail I took apart an old kids toy car, removed the motor circuit board and attached them and the car's battery onto the lock - now I can use the car's remote control to lock the door from anywhere, even when I leave the room. So fun, cheers for upload!

when I import the gear rack it looked like it was cut, so one end is sharp. is that supposed to happen?

It should like exactly how its portrayed in the project photos and on the Thingiverse viewer

It was mentioned in the Summary. "40.8 × 20.1 × 38 mm"

What is the size of the largest part

Can we have the design files? I want to modify something a bit if that's okay. Thanks!

Hey there, you are great. I'd like to use your design with PowerHD HD-3001HB servo motor. Dimensions are: 40.7x20.5x39.5mm. Thank you in advance.

Thanks for the amazing design. As few others have requested, any chance we can get the files for the TowerPro SG90 servo? Dimensions: 23×12.2x29mm.

All I can think about is that one amazing spider man movie

Any chance to scale this for SG90 sized servos?

How well does the the gear work without it catching the teeth on the servo? Will it withstand some resistance without skipping?

It should be fine. Just make sure that the mounting screw is pretty tight. Your servo motor will usually come with a pack of screws for mounting but it shouldn't have any resistance, its simply pushing a very light weight rod into the holder, you arent trying to move a large weight.

if you guys don't want to use a servo motor for this lock, you can also use a dc motor and then open and close the lock with a 9-volt battery by switching the positive and negative poles so it goes back and forth.

could you please upload the file for towerpro sg90

Hi. Thank you for this project. Can you make something for 23.1 x 12.2 x 29 mm micro servo ?

Hi, I am Currently Prototyping a remix of this design for 23, 12mm micro servos. Find Attached STL's! Just Use My Gear And motorholder along with original Components! :-)

What is the type of motor you use? I looked on amazon and i found one but I'm not sure about it. can you send a link to where you got it?

Hey, it's a standard sized servo. You dont need to buy the exact one I used, just purchase one with these measurements:
40.8× 20.1× 38 mm. They're not all exactly the same, it might be a mm or so difference between models but they should all fit just fine.

Here's one that will work from Sparkfun: https://www.sparkfun.com/products/11884

Really cool design, I am using a Fitec FS5106R compatible servo but I am finding the mounting hole too small.

In your files, the completed project looks as if the Motor Holder is square, but in the Motor Holder pic there is a step/shoulder in one corner.
Is that supposed to be there ?

Another odd thing is I can't seem to edit the .stl, it imports into meshlab just fine and I can slice it with Cura, but it won't import into TinkerCad or OnShape. The import does not complain about errors but the shape is all malformed.

Besides the hole for the server, the rest of the part seems to scale and the other parts fit fine. I hacked away at the hole with a saw and besides exposing the in-fill, it seems to work, I would still like to print a better part.

What software package did you use to initially design the part ? If you used TinkerCad or other online program can you share a link ?

Thank you for the upload, my son is looking forward to building the project.


Hi John,

The new models have been uploaded. Please reprint the motor holder and rack mechanism. The rest of the files are still the same. The model should be stronger and any model issues have been solved as well as the mounting area has now been corrected.

Wow, thank you for the quick reply. I had asked what CAD package you had used because I originally came across your design in this post. https://www.youtube.com/watch?v=NrtOJ2vGBlQ My plan is to build that with the remote control lock, then take your Motor Holder and graft on a box to hold the receiver, p/s, and battery. With my 5yo, I need to play by preK rules, so he can take to show & tell, that means no exposed wiring or lipo batteries. I was able import your previous .stl file into Microsoft 3D builder and edit, so I should be able to do that again. If your design was already in OnShape or TinkerCad, it would just be easier for me modify.

I can contribute the modified motor holder and connection schematics if you want.

BTW, nice job on the clean up, mounting holes and all, I like it.


Oh hey, i didn't even know my door lock was featured on his video XD. I actually used 3DS Max which Im not very good at. I redesigned the model using Autodesk Inventor and ill most likely upload the file as well. It honestly needed to be redesigned anyway, the mesh was completely destroyed while making the model with all the boolean operations i used. If tinkerCAD can import OBJ files or something similar then let me know so I can export it from Inventor and you can do whatever edits you wish. Like you said, the mesh was damaged when you imported it but if you import the new model in any program it should be perfect to make some edits on.

Make sure to post the project on the "Made" section so we can have a look at how it came out :)

I have used Inventor before, I really like that package and Autodesk has a friendly edu license. TinkerCad is a really good, super entry level, solid modeling tool. I really like how it does subtraction by grouping a "hole" part with a solid part vs the cut style subtraction feature of MS 3D modeler. Where tinker CAD falls short for me is not being able to take measurements from arbitrary points and any notion of making an assembly. I just found OnShape from another Thingiverse project, it looks really nice, a lot of parallels to an Inventor / Solidworks style package and claims to import parts from many other systems. If you are ok with shared projects, the system is free and it supports full assemblies and looks like you can create fairly complex systems. I haven't used it for anything besides watching a few tutorials so far.
Since you want to share you project I would suggest looking at OnShape and creating an assembly, then animate it. See here https://www.onshape.com/videos/lets-make-an-assembly

Usually .stl files import very easily into TinkerCAD, it can import directly from a ThingFile URL's and it comes across nicely but it seems that 3DS is using a .stl format that doesn't import into TinkerCAD or OnShape very well, although it will import into Cura, MeshLab or MS 3D Modeler just fine.

Will definitely post on the made section and add my files on a ReMix.


Hi there,

I must apologize for my mistake. It seems like I uploaded the incorrect file years ago. I made two mounts, one for a smaller servo (which you printed) and one for the standard size servo motor. Ive uploaded the correct model labelled "Motor_Holder_Large_Servo" which you should be able to download and print. This is designed to fit a 40mm wide servo so this should work perfectly for you.

By the way, that little step was placed there to allow the correct mounting height of the smaller motor, its only a single step because I thought it would print faster. Just keep in mind that I will be recreating this model, it will have a similar shape and size but other members have reported an error with the CAD model. I will also be removing the limit switch ports because I doubt many people are using it. If you want to wait until the end of the week for a better designed model then just hold off on the print but otherwise go ahead with the newly added model. If the first one printed well then should should also.

What is the entire code script that you used to make the servo move. Also, where did you buy the servo?

Servos can be bought from any electronic store. The code is up to you and dependent on the micro-controller or circuit you use. Arduino has a built in example in the IDE.

Dude this is an awesome make! what i did is attached a daylight sensor to it so when i i turn on the lights in my bedroom it unlocks and when i turn the lights off it locks, great for keeping petty sisters out of your room at night!

Looks like the fix never made it to thingiverse. The motor mount still cannot be sliced in Cura.

Hi Cross,

The new models have been uploaded. Please reprint the motor holder and rack mechanism. The rest of the files are still the same. The model should be stronger and any model issues have been solved as well as the mounting area has now been corrected. I have tested the model in Simplify3D, replicator G and Makerbots software.

Awesome! Do you think this will work with a smaller servo like HXT900?

No it wont. What you can do is just design a plate that has the same size cut out as the servo you have and attach it to the back or front of the existing cut out with some nuts and bolts. You can also order a normal sized hobby servo for a few bucks off eBay or Amazon.

very cool I have made ​​it in carbon fiber
it is very strong, very cool design!

What do you connect the servo wire to?

A micro controller

No not by itself. You will still need a circuit to run the servo motor. Either a 555 timer PWM servo circuit or use a micro controller.

Do you mind sharing which micro controller you used? Please

I used an Arduino Mega but I also have a home automation system. If you just want to drive the door lock, an Attiny 85 will probably work fine.

Would it work if I get a Rc transmitter and receiver then connect the servo wire to the reciever?

No not exactly. A servo requires very specific pulses that your receiver wont do. If you connect a receiver to a microcontroller and program it, which is pretty simple, then itl work.

Do you mind helping me with the code (I'm new to this) if I get the arduino mega 2560?

The code to make a servo move is in the Arduino example and there are thousands of resources online that will get the job done for you. I also suggest buying an Arduino Uno, a Mega is too overkill for a simple servo driver. (Well an Uno is also overkill but a bit less than the Mega)

I would use a pro mini - cheap as chips and still plenty good enough

Comments deleted.
Comments deleted.

what is the servo motor you're using please ? ^^

It's just a generic 180 degree standard servo. I specifically used the Fitec FS5106R

thanks, was more interested by the brand to know its dimensions ;)

By the way, simplify3D and repetier have troubles slicing it... some parts of the holder are really strange
EDIT: nevermind https://modelrepair.azurewebsites.net/ fixed it ;)

Hmmm sorry about that. I usually use Skeinforge but ill take a look to see if there are any mesh issues and re-upload.

yeah ^^ with repetier I used Slic3r btw ;)

I tried with skeinforge but there's an error too lol how did you do ? btw, could you look at it soon ? the version that was fixed by nettfab for me has a little problem too ...

I actually have no idea why you're having an issue. I sliced mine with Replicator G and the MakerBot software and both came out perfectly. What software are you using?

I told you, I used Simplify3D, Cura and lastly Repetier (using Slic3r engine). They all give the same results... parts of the motor holder aren't "sliced" and the 3 programs detect mesh errors

An other problem apart the mesh errors detected is the scale. I have to print it at 108.11% x scale if I want to have the right dimension on the hole to hold the motor ! (by default it's 37mm20mm long instead of 40mmx20mm...
I wanted to use this in a school project btw ;)

Hi there,

The new models have been uploaded. Please reprint the motor holder and rack mechanism. The rest of the files are still the same. The model should be stronger and any model issues have been solved as well as the mounting area has now been corrected.

I found the issue you were having in Cura, Im going to remake the model in another program soon so itl turn out a lot nicer. Im not too sure about the scale, It held my motor perfectly but im guessing the programs you're using isn't slicing my model properly. Just give me until next week and ill repost the motor holder :)

Comments deleted.

Parts could have metal embedded into them for strength. Just need to calculate it into the build. and add the metal at the rite point in the build

Ya know. At first I chuckled a bit about its security (not the coolness of it). But just glue/screw the rack to a metal bar, and use metal 'loops' on the door and jam; it can work.

Despite the fact its made out of plastic, you will find it extremely difficult to break open your door once its locked. I've tested it and I'm unable to run down the door, I wasn't generous with the kicks or shoulder slams by the way :P. I guess if you want something permanent you could make a mould and then cast it with metal.

It will be strong enough to keep an honest person out. It's no where near strong enough for the zombie apocalypse. Anode has the right idea. If this were tweaked with a metal bar getting the linear motion from the printed parts and then some metal brackets positioned in the overall assembly by the printed parts. Where do we source the metal parts though? and how to we do it so that the metal is widely available? I think coat hangers would be the best resource. This is thin enough that we could bend the wire with printed tools and to make it strong have many metal wires reinforcing each other. A bundle of 50 wires from coat hangers is going to make a very serious bolt in a door.

The screws are metal and if they are attached to plastic, that will be the weakest point. It would be best if the screws were going through the metal brackets.

IamTeknik put this into the creative commons, so this idea is definitely worth some additional effort. Thank you ImTeknik.