Introduction: Watch From Metro - Last Light

Hello Instructables community.

I am a huge Metro fan and wanted to give back to the community so I've designed this watch.

Step 1: Step 1: Get Your Gear Together

* 1 x "Blue LED"

*1 x "0.36 inch 4 Bits Digital LED Tube Module With Clock Display TM1637 Common Anode"

* 4 x "20mm m3 cheese head bolt/screw" (slice off at bottom of circuitry holder)

* 1 x "Arduino Nano or Pro-mini"

* 1 x tactile momentary switch"

* 1 x DS3231 Real Time Clock Module w/ I2C Interface"

* 1 (or many) x CR2032 Lithium Battery" (Last between 1 to 3 years)

* 1 x "3.7V 200mAh 402030 Lithium Polymer Li-Po Rechargeable battery"

Extra Materials you may need:

*3/32" drill bit

* 2.5mm drill bit

* M3 tap

* Chisel or sandpaper

Watch Straps:

* 2 x "25mm watch spring / bars / pins"

* "25mm Watch buckle" (one size smaller would be ok as well) "

* "25mm Cotton Canvas Webbing Dark Olive Green"

* You only need the 3 (Arduino module, TM1637 Module, Real Time Clock ) for testing, all others are complementary.

Step 2: Step 2: Arcitecture of Circuit Board

See picture.

I used the "TM1637_DS3231_cloc0a.ino" sketch.

Download the library at:


Just re-file the folders accordingly. You'll see why.

Step 3: Step 3: Design the Watch

Since the included circuitry was a little to big, I had to amend the sizing of this watch.

View .SLT file on Autodesk server:

Link provided to download out of site:

Step 4: Drill, Ream, Tap

The eight holes: 4 being on top of the watch; 4 being circuitry holder.

3/32" drill to ream to out the eight separate holes.

2.5mm drill bit them cautiously and slowly to prevent tear out, snapping, or cracking.

3M Tap each and every one them slowly.

The tapped shadows seem to be finicky in the light, so you might mark the done ones (on the bottom) to the undone ones. :/

Screw in the bolt and mark out where it protrudes from the base.

Disassemble all pieces and cut the bolts with bandsaw, hacksaw, jewelers saw, disc cutter, dremel, bolt cutters, wire cutters, or what have you.

Step 5: Step 5: Re-Assemble and Cleanup

*Chiseling the edgework so the 4 diode LED fits through.

*Sandpaper or filing for touch up's.

Re-Assemble the watch,

Step 6: Step 6: Solder Everything Together

This is a work in progress.

Step 7: Step 7: the Band

+Step 1:

Superglue one edge so that it doesn't fray. (I oversaturated it XD)

+Step 2:

Measure down 1 inch, superglue a glue bead the width of the strap and bind that end to it. (I used a thick bead)

*You may need clamps so that you get good adhesion.

*Bind it fully once again if you're finicky. (Again, I oversaturated it XD)

+Step 3:

Heat up an edge of a box cutter with a flame.

*Use a stove or a lighter, but don't melt the lighter.

*Don't breath the fumes, it is bad for your health.

+Step 4:

When it's deep black to glowing blue color, stop , mark the center (I forgot until now) and touch the box cutter to the fabric hard and cut with sawing motion.

* "Cut" down deep enough so that you'll get the watch buckle through.

* Remember, don't cut on something fleshy or irreplaceable. Something hard will do just fine. XD

* Re-Superglue as needed, the smell will dissipate after some time. XD

+Step 5:

Link up all the watch buckle pieces.

* It may take time and a lot of trial and errors, but eventually you'll get there. I did it on the 12th try.

+Step 6:

Fit the webbing fabric under the slots in either side of the watch.

+Step 7:

Snap the watch bars into the slots on either side of the watch.

+Step 8:

Wrap the webbing fabric around your wrist, add a around 2 extra inches or so.

+Step 9:

Get off of your wrist, and lay the band down.

Heat up the knife and cut off the rest of the fabric.

+Step 10:

*Follow +Step 1.

+Step 11:

Re-wrap the watch + band around your wrist, snuggly pull it through the strap, bind the clip to the weaving band and mark it with a marker.

+Step 12:

Heat up any pokey metal piece, such as an icepick and quickly stab through the mark.

* The heat will dissipate quickly, so multiple stabbing may be needed.

~ Your done with the Band.


Will put pictures at a later date.

Step 8: Step 8: Put a Cover Over It.

Disassemble your watch, place down a 1/16" - 1/8" plastic sheet down.

Find a circular piece that just fits into the hole, maybe an off-cut in the bin or some-such, and draw the perimeter.

~ Or you can just use this inner 47mm ring to sketch it out.

Cut the piece out a-little larger and sand to the correct size.

Extend it up to the top of the watch and mark the screw holes one-by-one.

Drill 'em.

Ream them with a 3/32" drill bit.

Follow with a larger 2.5mm drill bit.

Tap each one with a 3M tap.

~A work in progress for me >.>

Step 9: This Is Still a Work in Progress.

*The watch may eventually change over time.

*The digital clock will get out of sink with normal mean time in your area after awhile.

Step 10: Afterthought About the Instigation for Making This Watch.

It is true that throughout my time designing the underpinnings of this watch, much cash was wasted on such vain efforts.

If you personally have the sums of cash needed to make such an over indulgent purchase of over 15 different products; if at the very core of you do you need to build and test, then I say feel free. Whole heartedly step into the breach.

Arduino Contest 2019

Participated in the
Arduino Contest 2019