Today I focused my attention on making sure that the printer can properly draw an image onto paper using a pen. I figured that this is an important step that would help weed out problems early. And it did. Lots of them.
One problem that I noticed late was that one of my axes are actually flipped. It was only when I tried printing a word did I notice it.
That's supposed to read "Dianne".
This was easily fixed by changing a setting in firmware that sets if an axis is inverted or not.
You will also notice that there are extra lines that the printer draws to get to one point to the next. These are supposed to be non-print lines where the hotend does not extrude filament. Since I'm using a pen I had to manually add gcode before and after these non-print commands to raise and lower the pen when needed. The solution worked beautifully but is useless once I do use an hotend.
Another problem I had to deal with was leveling the bed. My design doesn't have a fancy auto leveling system so I'm doing everything manually. This meant checking all four corners by eye with the aid of a magnifying glass, and adjusting nuts and bolts all over just to get the perfect level. It's frustrating but is satisfying when the expected results are met.
It took a lot of time, ink, and paper but it was all worth it. Watch the machine print out "Mahal kita, Dianne", it's Tagalog which translates to "I love you, Dianne" in the video below (Pardon the cheesiness, I want to impress the missus :P)
You will notice though that the printing head moves all over the place. This is because the file I used to make the gcode is not optimized for printing as a 2D image. Will try to look for an optimized image to print next time.
I learned a lot from this step which made me more confident when the time comes that I actually need to use a hotend. Which is what I'll be working on next.