Reverse Clock





Introduction: Reverse Clock

This is kind of a response to Glitchmaker (, but not really.
As the name suggests this is an instructable where I will endeavour to show you how to make a clock tick backwards and also to draw your own clockface by hand.

Step 1: Step One

Firstly you need a clock, but I strongly suggest getting two, or maybe even three, of the same clock, because this is really easy to phuk up, and if you can work out how to do it, but then you phuk it up, at least you know what to do for the next clock...
And I forgot to take a photo of the clock before I started working on it...sorry...

You will also need these tools:

HB Pencil

Sharp scissors

Stanley knife

Mathomat (if you don't have a mathomat you can use a ruler and something round to draw circles)

PVA Glue

Step 2: Step 2

Take the plastic cover off the face of the clock, then carefully (I cannot stress this enough, whatever you do to the mechanism of the clock, be extremely careful) take the hands off the clock, they will generally be in this order :




You can use the plastic cover from the clock as a handy bowl.
Once you have taken the hands off carefully extract the mechanism housing from the rear of the clock (you may have to sort of pop it out over a ridge or perhaps push back a pin or something)

Then, again carefully, open the back of the clock.

It should look something similar to this (your clock mechanism may not be propped up against a lighter as is shown here.)...

Step 3: Step III

Carefully (remember what I said in step 2) remove the gears one at a time, as shown in this series of photographs. You may want to photograph the workings as you take them out, as I have done here, to remind you of where the pieces go.

Step 4: Step Four

Now, carefully, remove the cog with the magnet on it's base from the electromagnet, as shown in the photographs.

Then, to reverse the motion of the clock, what you have to do is you have to lift the electromagnet from it's base, where it sits upon two or three pins. Carefully slide the coil of copper wire off the U shaped ferrite rod. DO NOT UNWIND OR BREAK THE COPPER WIRE! The ferrite rods are usually in two parts, so try to keep them togeather. Then turn the ferrite rod over, so that the hole in the ferrite rod still goes over the hole where the cog magnet sits.
When you turn the ferrite rod over you may find that the pegs that it sat on when it was turned over no longer fit, so you may have to remove one or more pegs.
Your electromagnet will have to be held from moving inside the mechanism, so there will still have to be enough pins to hold it from moving.
If there are not enough pegs to hold the electromagnet you have two choices, either superglue the ferrite rod to it's housing, or get a different clock.

Step 5: Step 4.11

This is a detailed examination of the ferrite rod reversal process, in colour!

Please refer to photographs...

Step 6: Step V

Now all you have to do is to reverse the process, by carefully replacing the cogs, one at a time, back into the clock mechanism.
Make sure that you put the cogs back in the the order they came out in, and make sure that they are back in the right way up.
Also make sure that the teeth mesh.
And be careful!

Step 7: Step 6

Now you must carefully replace the cover on the back of the mechanism housing.
Do this with care, as there are small holes on the inside of the cover that the pins on the top of the cogs must align with.
Once you have closed the cover insert a battery into the battery housing and check to see if the clock ticks.

If so proceed to the next step.

If no, now is the time to take that second clock that I told you to get and start again from Step 1.

Step 8: Step Se7en

Now you have to make a face for your clock.

Either you can skip the next couple of steps and just print one out on your computer, but I drew mine by hand, so to see that process follow me onwards through these next few steps...

First I thought that I could just measure my clockface and draw the numbers in, as shown by these photographs.
But, as these photographs also show, my numbers did not stay a constant size.

Step 9: Step Eight

So, instead of trying to draw the numbers freehand, I used my Mathomat to draw a series of very faint circles of the same size around the edge of the face. I then used those circles to judge the size of the numerals against the size of the other numerals on the face and thusly keep them in proportion, as these photographs show.

Step 10: Step IX

If you decided to print your clockface on your computer, this is where you should rejoin us:

Now you have to cut out your clockface and glue it to your original clockface, as shown...

Then, once the glue is dry, form a hole in the centre of the clockface, to allow access for the mechanism.

Step 11: Step 10

Now, reinsert your clock mechanism into the recess at the rear of the clock, make sure that the mechanism is properly housed. If you broke the pins on your mechanism holder when you removed your mechanism you have two choices, either superglue the mechanism into the recess, or take the other clock, carefully remove the mechanism, taking care not to break the pins, and use the other clock as your new clockface and housing.

Step 12: Step Eleven

Now carefully replace the hands onto the spindle of the clock mechanism, generally in this order :




It will be the reverse of the order that you removed them.
They also must have adequate clearance between them, or they will not be able to rotate properly and stop mid-rotation.

Also you must replace the plastic cover over the face of the clock.

Step 13: Step XII

If you choose you can go over the numbers in black, or any other colour, as I have done here.

Step 14: The Thirteenth Step

Now all you have to do is set the correct time on your reverse clock and wait for people to phreak out as they try to work out what time it is.

This work is in the Public Domain. To view a copy of the public domain certification, visit or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA.

Step 15: Addendum

Since I have made this instructable (March 2009) there has been a devastating flood in Brisbane, where I live. My entire house was under water, with water up to the roof in every room. And these are 10ft high ceilings.

Anyway, the point is, after we re-entered our house, we found everything near destroyed, as pictured below

However, I found, still hanging on the wall where I left it, still ticking, my reverse clock, as evidence below.

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It works...I just did it this afternoon with an old clock.

I also printed numbers on my computer and glued them on backwards. The clock looks perfect in the mirror :)


Could you use something else to make the circles like this?

So sorry to hear about that flood! But glad to see that clock still ticking. Will try to make one myself. :)

I like the clock, very nice. Also, it's comforting to know that if my room ever flooded it would look the same as it does right now. Thank you and I'm sorry that your house got flooded.

I reversed a clock for a friend a few years ago.  His clock had a worm gear in the drive train.  I pulled the worm gear off its shaft and put it on backwards.  Done.

That makes sense...? I wish I could do stuff like that.

the two wires of the coil, can't you switch those two for the same resutls?

if I flip the coil, is this the same effect as flipping the metal rod, cos I have clock that has asymmetric rod!! so it is impossible to flip rod! how to make this clock to run backwards??? just to say, i flipped coil and nothing happens! WHY!!!!