If you have already built your A8 or any other DIY printer kit you will have a good idea of just how many components build up this machine. The best thing about building from the ground up is you get a fantastic insight into how they take the most basic and commonly available hardware and create a complex and ingenious design. Building it this way makes it easier to understand how it all goes together and where you can start making improvements. The simplicity of the design means you can make small improvements here and there without having to entirely dismantle the printer in the process. It’s also highly beneficial that a number of mechanical upgrades can be produced using the A8 itself. Whether you’re adding or replacing parts you will be able to find a vast array of ideas on the internet and forums. The A8 is highly talked about so there will always be an answer to your problems if you get into any trouble.
For the simplicity of replacing existing parts or printing new upgrades I have detailed below a list of all the mechanical components that build up an A8 to give you an idea of what particular parts to look for.
- Threaded Bar
- Smooth Guide Rods
- Linear Bearings
- Lead Screws
2 x 400mm lengths of M8 threaded bar are used to support the base of the A8 and provide the overall stability. These are positioned through the 3 parallel walls that make up the bottom of the printer and secured using a series of M8 washers and nuts.
Smooth Guide Rods
Sitting slightly above and running in parallel to the threaded bars are 2 x 380mm aluminium M8 smooth guide rods. These are not structural and sit freely in holes in the front and back panels of the frame. The purpose of the guide rods is to allow the heat bed to travel back and forth in a smooth and stable motion.
A second set of 2 guide rods are used in a similar fashion but for the extruder motor. These sit in between the 2 Z axis lead screws and allow the extruder carriage to glide left and right.
Lastly, a set of 2 guide rods are positioned vertically in parallel to the Z axis lead screws. These go from on top of the Z axis motor housing, resting on the motor, directly upwards and through a hole in the top plate of the frame.
There are 7 linear bearings in total. 4 are affixed to the underside of the heat bed carriage and are slotted in pairs onto the 2 guide rods found on the base of the printer. The remaining 3 are located on the extruder carriage in an upside down triangle formation and slotted onto the X axis guide rods. The bearings; in conjunction with the guide rods, provide the bed and extruder carriages with a smooth, stable and uninterrupted path when in motion.
2 x 350mm M8 lead screws with an 8mm pitch are used on the A8 to provide the vertical motion on the Z axis. Motion is achieved by the Z axis motor rotating a flexible coupler which is connected to the lead screw via a set of 4 M4 x 5mm grub screws. Check there are 4 on each side and they are securely tightened. Use sewing machine oil to lubricate these screws to keep them operating smoothly and efficiently