# Assembly guide
## Required Tools
* A vise
* A 2mm drill bit
* A screwdriver (PH1, 2.5mm hex key)
* A FDM 3D-printer
## Required Materials (BOM)
* 1 SG90 Micro-Servo (Including the screws they usually come with, one to screw in the servo horn, two to screw the servo into the frame)
* 8 2x12mm Dowel pins (m6 tolerance)
* 4 M3x10 socket head cap screws (DIN 912)
* ~25g of PETG 3D-Printer Filamet
## Prepearation
All parts in the step-export need to be printed.
The lower and upper linkage halves, as well as the bell crank need support, which will need to be removed before proceeding.
All 2mm holes need to be drilled to actually be 2mm (Most printers will print them significantly undersize). This is easily done without an actual drill, just by clamping the drill bit in the Vise, and turning the parts on it with some light downwards pressure. Carefully to roughly maintain alignment with the existing hole initially, though once started the drill will follow it. Once through give the part a few turns on the bit to ensure that the hole is fullly formed and round.
On the upper half of the Crankshaft, run the drill through the holes a few more times to ensure it will slip onto the pins of the lower half easily.
## Assembly
Connect the servo to a way to give it an input (for example a microcontroller), and set it to 0°.
Insert the Servo into the cutout on the lower casing. Ensure that the output is on the correct side, in relation to the rest of the linkage. Check the 3D model if unsure. //todo add pictures .-.
Screw it into place using the two longer screws included with the servo.

Insert the three pins into the lower half of the crankshaft. Ensure that the chamfered end is facing the upper half, and that the other side is flush with the bottom of it.
Push the lower half of the crankshaft onto the servo, aligned so that the crank pin is facing the outside (top) of the housing. This should take a little bit of force, though it shouldn't be enough to worry you of damaging the servo.
Screw in the final screw that came with the servo through the lower half of the crankshaft and into the servo output shaft.

Insert the centre pin of the bell crank, so that it pokes out 2mm either side, as well as the pin that will make contact with the tube, it should poke out a little further on the bottom than the top (by about a millimeter more).
Take the bell crank, and the two halves of the linkage arm and push the pin through them. Ensure that the linkage arms halves are correctly oriented to give the clearance for full range of motion. This pin should poke out either side equaly.

Push the other half of the linkage arm over the crank pin of the crankshaft, and position the bell crank in it's final spot. Then push the upper half of the crankshaft onto the lower, trapping the linkage arm between them.

Insert the opposing contact pin, as well as the bearing pin for the crankshaft into the upper half of the casing,
Push the upper half of the casing onto the lower, ensuring everything is seating where it needs to be as you do.
Screw in the 4 M3x10 screws to connect the two.

Slide the tube into the slot in the front and connect the servo to power. Test the range of motion to ensure it can fully open and close the valve.