So, now for the electronics element of this project.
Control Board
There are many 3D printer control boards out there. I wanted to go with one that has a good ecosystem and has good support. For this reason, I decided to go with the RAMPS 1.4. It is limited in it's processing power, but it is well established, and has wide support, not to mention a number of firmwares that can be used.
The RAMPS series of controllers are usually one part of a two part system. The main processing element of the setup is an Arduino Mega 2560. This board is responsible for receiving and processing the gcode and then calculating how the printer will move to match what has been requested. There are some custom RAMPS boards out there that incorporate the Arduino on one board. I decided to stay away from these due to the fact that if the 3D printer didn't work out, I could use the Arduino for another project.
The RAMPS board allows the Arduino, with the addition of a suitable power supply, to interface with the stepper motors, sensors and heating elements, of which will draw more power than the Arduino can supply.
Although I would recommend purchasing an official Arduino and RAMPS boards (I already have an official Ardunio Uno), I opted to order up a version from a well know Chinese supplier. This was mainly due to the fact that I had to keep the costs down. As a result of this choice, I was expecting to have to deal with some quality issues later on down the line.
As part of my order, I also decided to include a full graphics module. This seemed better that the 2x16 screen and also gave me the ability to print directly from an SD card.this seems a small point but it is worth noting if your PC crashes for any reason that 5hr print has just been ruined.
So after a few weeks my order arrived. Surprisingly it came in a nice plastic box and in sealed anti-static bags. It came with "almost" everything I needed to wire up and get going (We'll get onto the "almost" later).
The package included: -
- 1 x Arduino clone
- 1 x RAMPS clone
- 5 x DRV8825 stepper driver (1 for each axis and enough for 2 extruders)
- 5 x Heat syncs for stepper drivers
- 1 x Full graphic display
- 1 x Adapter to connect display to RAMPS
- 1 x USB cable
On first inspection, the quality seem very good. But while I was attempting to connect the RAMPS board to the Arduino, I found that there were issues lining up all of the pins. It later transpired that the headers on the Arduino were leaning slightly and this was obvious that this was done during manufacture. The cautious application of force in a strategic area sorted the issues and all went well from there.
As I said earlier, the deliver came with "almost" everything that I needed. For some reason the supplier decided not to provide me with the required jumpers that allow the RAMPS to do micro stepping. In short, microstepping allows the motor that drives the printer to be controlled with a greater level of accuracy. Thankfully my hording of old computer equipment provided me with a bounty of redundant jumpers from old motherboards and hard drives.
Now it was time to prepare the DRV8825 stepper drivers to be installed. This was relatively easy, but care still needed to be taken due to very tight tolerances between the top of the driving chip ad the back of the headers. To install the heatsync, it was a simple case of removing the thermal tape paper, aligning the heatsync with the chip and pressing down, while at the same time making sure the heatsync was not touching any other parts.
Nnext up, the driver boards need to be inserted into the RAMPS board. Again, this was relatively easy, but care needed to be taken to orient the boards correctly. If these are plugged in backwards they fry the driver chip, so it's best not to get this part wrong. to install them, the small trim pot needs to be furthest away from the cower connectors. the picture below shows the green power connector on the left and the small round trim pots on the right hand side of each driver board.
I'll do my very best to recreate the process to complete the build, but i was having WAY too much fun at this point :)
Until next time