BotMill's Blog

Now that we have completed all assemblies required, we can go ahead and put together the X-Axis. First, lets summarize the assemblies we have prepared to get us to this point:

- Carriage (completed with extruder, see extruder)
- Idler Bracket
- Vert Bearing 180
- Vert Bearing 360
- Motor Bracket

The order that the assemblies are attached to the X-Axis smooth rods, when facing the front of the machine, from left to right, is as follows:

Motor Bracket-spacers-Vert Bearing 360—–Carriage/Extruder—–Vert Bearing 180-Idler

You may install it however you please, but we like to begin with the Motor Bracket. Be sure to insert the smooth rods so that they are flush with the belt clamp pieces. Repeat this on the other end for the belt clamps on the idler bracket as well. Be sure not to forget the spacers that go in between the Vert Bearing 360 and the motor bracket. Once all the assemblies are on, go ahead and tighten anything that it still loose, one by one. Here are is a breakdown of important items we have left loose on each assembly to ensure proper installation:

Motor Bracket – 4 M3 Nylock nuts on the X-Bar M3 clamp pieces (outer screws), 4 M3x20 screws attached to the motor (motor screws might already be tightened all the way depending on how you’ve gone about it)
Spacers – n/a
Vert bearing 360 – 4 M4x40 screws (2 for each clamp piece) on the X-bar M4 Clamp pieces
Carriage/Extruder – n/a
Vert Bearing 180- 4 M4x40 screws (2 for each clamp piece) on the X-bar M4 Clamp pieces
Idler bracket – 4 M3 nylock nuts on the X-Bar M3 clamp pieces (inner, outer screws)

Belt Installation

Installing the belt can be a stress-free process if you adhere to the following procedure. First, wrap the belt around the entire axis, ensuring that the teeth of the belt are wrapped around the gear, and the smooth sides are wrapped around the four (4) bearings on the motor bracket, and two (2) bearings on the idler bracket. Slide the belt behind the two belt clamp pieces on the carriage, which should already have two M4x40 screws (with washers) already installed. Once the belt is inserted behind the clamp, insert two more M4x40 screws (with washers), and pull the belt, forming a small loop. While pulling the loop, which will tension the belt, use an M4 hex key to tighten the screws. Note that you trapped M4 nuts in each hole on the carriage, so it will tighten properly. The result will be wonderfully tightened belt. Be sure not to tighten the screws too much. A good way to test if the belt has successfully been installed is to turn the gear in each direction. If installed properly, a single turn of the gear (called, a “step”) will result in the X-Axis moving one exact step as well. If it is too lose, the X-Axis will move more than just one step. If too tight, it will not move at all. Using these hints will ensure perfect X-Axis. This concludes construction of the X-Axis.