The first addition was making a mounting bracket for the idle wheel. This was made similarly to the Y axis but was altered slightly to all exist on one bracket which could be screwed onto the extendable side. After this the belt was added, and just like the Y was tensioned, the whole X structure now screwed together. After testing that the Y structure's running by hand an issue was found. One runner of the 4 was elevated slightly due to it being slightly too far out. As a result it ran along the top of the flat aluminium rather than beside it. This could cause issues in operation or locks in the motor so I quickly fixed this. To do this involved taking the bracket and wheel off and remaking it completely, this time slightly less out, and with the runner slightly lower. After this rework, the Y axis ran smoothly as required so well it ran when tilted under the force of gravity.
Next, a small bracket was made and screwed to the Y axis structure. It was positioned directly in line with the motor, the piece which would connect the belt to the Y structure. This consisted simply of 2 pieces of angle and a piece of flat aluminum for the belt to rest on. Another piece of 3mm flat was then screwed on top to lock the belt. However upon doing this, another issue arose. As previously predicted the motor and idle wheel brackets were slightly too long causing the belt to not sit flat. In operation, this would cause the belt to lock when it got close to the idle wheel or motor. Hence, both brackets were raised and then screwed in again which solved the issue. This finalised the building of the primary X-axis structure.
With the structural completion of the axis's, electronics started to be added. The simplest of this included another limit switch to reset the position of the X-axis when the centre of the Y-axis structure activated the switch. The harder piece was the photo interrupter. At first this was attached just like on version, simply soldered straight onto shielded cable. However the shielded cable was not very flexible and as a result it interfered with the movement of the X-axis and eventually caused the photo interrupter to break. Thus a new photo interrupter was used however this time it was attached tot he cable differently. Firstly, the photo interrupter was fed through a small piece of experimenters board. It was soldered to this and then trimmed very short. Next the wire was then soldered to the back of the experimenters board in a vertical position as shown in the image below. This made it so the wire would not touch the X-axis structure at all. To hold all this in place and ensure a break would not occur again, hot glue was used to act as a sealant for the solder and wire. This was then cut to size using a band saw and a hand held drill was used to drilled holes to fit M3 screws. These allowed it to be screwed into the Y structure and stay in a static position at which it could accurately need the encoder wheel for the Y. This process was quite extensive and brought many issues however I am confident it will not do so with the X axis photo interrupter. This is because the X unlike the Y structure does not have to move. I also now had the experience and resulting new way to connect the shielded cable.
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