Picture of DIY mini drill
Hi guys, this is my first instructable, my english is bad, I take terrible photos, so... :)
In this tutorial I will show you how to make a cheap drill.


-DC motor
-Terminal block

Note: I found that the diameter of the compasses' leg's are 3mm in most cases. So try to find a motor with a 3mm axle, and the holes on the terminal should be 3mm too. With a 3mm terminal you can use any dremel tool, if you replace the "chuck".



Not necessary:
-Electrical tape
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Step 1:

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Take apart the compasses, we need the component marked on the picture.
Actually, it is a mini chuck. :)

Step 2:

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Now take apart the terminals with a knife. Remove the plastic, we only need the inner metal part.

Step 3:

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Mount it on the motor.

Step 4:

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Insert the compasses leg into the hole.
I replaced the screws with newer ones.

Step 5:

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Now we are ready. :) If you want you can solder wires and a switch to it. I didn't solder them, because I use it with crocodile clips.

You can easily use 2-2.5 mm drills, for the smaller ones you need to put on some electrical tape or thin wire to the drill to fit in the chuck.

Step 6:

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Now try it on an old PCB, or something else.
I give 12 volts to it from an old ATX psu.

Step 7:

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Here is my first DIY drill, I made it before the instructable. Actually it is the same, but I mounted a push button to it, and I put on some electrical tape so it is more ergonomic. :) I made this for only PCB drilling so this is why the the drill bit is so short.
roshany10 days ago

nice idea..

RoshanS410 days ago

awesome helped me alot....

ace11d71 month ago
This is an amazingly helpful instructable
ace11d71 month ago
This is an amazingly helpful instructable
JaganHari878 months ago

Really super i ll search 4 this type method last 2 month ,,,thanks

Kante Tech10 months ago

Thanks I have been looking at something like this for a while now.

TrieuIV11 months ago

This is a ideas interesting

wotboa11 months ago

Here is the method I used to attach a micro-chuck
to a motor. Maybe it will work for this project.

See the Instructable:

liamsi1 year ago


I made it, i try to find the compasses but i couldn't, so i try to made the same diameter the two things and it drills pretty sweet, regards from Quetetaro, Mexico.

brunoip1 year ago

great idea, just made mine


where i can find that terminal block thing? is there any appliances or a gadget that has one? please reply i making my version of there which not just a drill but a dremel also. but i'm stuck with the terminal block because i cant find that thing... any help?

man it is found in all hard ware shops

ottawafm1 year ago
Love this instructable! Lots of ideas. Where did you get the compass?
jeffc611 year ago

Very nice work. Once again we see necessity being the mother of invention.

Very clever and well done!

You need someone to 3D print you a cover for the drill! GREAT job!

gigin1 year ago

I like your idea, very clever..

djokenzi1 year ago

Good job! I will probably make one of those myself.

lean041 year ago


very clever shaft-coupler adapter!!, it´s an instructible on itself..

Mad Max would be proud indeed..

i´ll make one as soon as i can

Szabolcs (author) 1 year ago

I added three more steps, I guess it looks better now.


Nice work and Congrats on being featured on

domints1 year ago

Nice idea. But doesn't it make problems with not centered axles? Because this terminal makes not self-centering connection, and if the compass part is smaller or bigger than motor axle it might be not centered and might strongly vibrate.

Szabolcs (author)  domints1 year ago

You're right. My first drill was vibrating like hell - because the compass' leg was smaller than the motor's axle. But now both of them are 3mm in diameter, and perfectly fits in the terminal blocks hole.

And about the terminal, so far It seems to me it doesn't matter.

francisdsa1 year ago
very nice. innovative. maybe you can extend it further by adding a handle which houses the batteries
Granzeier1 year ago

Very nicely done (and your English is better than many native-English speakers - sad, but true.)

I really like your idea for the chuck - that was a brilliant piece of imaginative engineering.