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Page 12 - Final Assembly

Now you have the 3 sections completed. All that remains is to join the three pieces together. This is a fairly quick section as well as being very rewarding. Be gentile with the sections as excessive flexing some of the dangling microwire can cause them to break.

The 3 Sections

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Before we start, lets review the existing connections each section has.

Watch Base:
Motor control wire
Motor power supply
Battery VOUT
Ground

Logic Frame:
Ground
Regulator VIN

Watch Top:
Ground
LED 1
LED 2

Now there isn't wire connected yet for the OLED screen, but we will be connecting it based off of the following schematic:

OLED Schematic:

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1.) Connect Logic frame to base

When connecting the two parts, keep the micro wire to a minimum, and use electrical tape around any solder joints. To connect the two there are 4 connections that need to be made. Also, cover the Lipo battery with electrical tape

Motor control wire - Microduino digital pin 17
Base Ground - logic frame ground
Base switch VOUT - Logic frame Regulator VIN
Base motor power - Logic frame Regulator VOUT

Beginning connection

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Almost Done

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Complete

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2.) Connect the Logic frame to the top

When connecting the two parts, keep the micro wire to a minimum, and use electrical tape around any solder joints. To connect the two there are 9 connections that need to be made. Some of the connections we have done could technically use different microduino pins (except for the interrupts). These pins also need to specifically connect as we are utilizing the hardware spi connections which makes rendering to the screen about 4x faster than software spi connections.

OLED Data - Microduino D11
OLED CLK - Microduino D13
OLED DC - Microduino D9
OLED Rst - Microduino D12
OLED CS - Microduino D10
OLED Vin - Regulator VOUT
OLED / LED Ground - Logic Frame Ground
LED 1 + - Microduino D22
LED 2 + - Microduino D23

Making connections

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3.) Assembly

Now that you have all three sections, gently place them together and turn it on. You should see the screen fire up, all the buttons work, LEDs, and the motor.

Checking the watch

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4.) Minding the gap

Once all three have been placed together, you can see how much of a gap exists. On the MkI, I had about a 3 mm gap that required me to print a piece of spacing and insert it between the top and base. On MkII I have about a 1mm gap. The gap is caused by slight impefections in assembly, such as larger than desired solder joints or non-flush wire runs in the logic frame. First, look for obvious offenders, such as wires or stray plastic blocking things from coming together. Once you have cleaned any obstructions, you have 3 choices. If the gap is minimal, you can just ignore it and continue. Or you can 3D print a spacer (avalable on the 3D printing guide page - here ) Finally (and the option I chose for this build) if you have flexible filament you can print out a rubber seal (also avalable on the 3D printing guide page - here ). The flexible filament will help create a tighter seal.

Gap study

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If you are going down one of the 3D printing routes, simply print the object, trim it to the required height, and glue it to the top, aligning it via assembly. Now screw the top down with the 4 screws and you have the core module completed!

Complete

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Next Page - The Strap

The Build