I have a stack of retired inkjet printers on my teardown waiting list, supplied by an industry whose ink cartridge-focused business plans render printers borderline disposable. I've learned a lot about electronics and mechanical engineering since my last inkjet teardown, so I'm going to do another one and I hope to get more out of it. Both in terms of knowledge and salvaging parts for potential reuse.

This Canon Pixma MX340 will be the next to receive the teardown treatment. I bought this around 2011 when I needed a fax machine and a scanner that can go directly to PDF on a flash drive. The automatic document feeder (ADF) on top of the machine made life easier when I needed to fax or scan a multi-page document.

Flipping open the lid for the ADF document feed tray, I can see sunlight over these years has yellowed exposed exterior trim. This all used to be the same color!

This machine is built with multiple hinged layers. Top layer housed the control panel and ADF. Lifting that exposes the flatbed scanner bed. Useful for items that aren't suitable for the ADF, such as books or items with fragile/wrinkled paper.

Lifting the scanner bed exposes the print mechanism. Nowadays I have a monochrome laser printer that handles most of my printing needs, because I rarely need to print in color. The last time I wanted a color print, I fired up this MX340 only to find the neglected nozzles have clogged. The unclog procedure didn't fix the problem, so I started thinking about replacement cartridges. I still have a 210XL black cartridge unopened in original packaging. No 211 color cartridge, though, and I only found a few places that would sell Canon 211XL cartridges. Asking price is about $35 which is discouraging when new color inkjet printers can be found on sale for about $40. The ink cartridge that comes in a new printer won't be the higher capacity "XL" variety, but I don't need a lot of color printing. In my usage pattern the cartridges tend to dry out and clog before I use up all of their ink.

This specific printer is so old even the aftermarket cartridge vendors don't bother carrying a compatible cartridge. Canon has discontinued support for this hardware, so it will never receive printer drivers for Windows 11 or Apple Silicon MacOS. Its WiFi connectivity is built around WPS, which is now considered insecure and not even supported by my WiFi router anymore. All of these reasons added together lead to the decision to retire this printer. I'll buy one of those $40 printers when I need to print in color again.

I opened my 210XL black cartridge and installed it in the printer, then tried an ADF copier test run. The dried-out/clogged color cartridge did nothing, but thankfully this printer was willing to print anyway. (Some of the more annoying printers will refuse to run with an empty cartridge.) The test run verified all mechanical components in the automatic document feeder, scanner, and inkjet printing engine are in working order.

Since the components are still working, my teardown plan will include a stage where I poke and prod a disassembled (but still running) device. I hope it will be educational.

  • Phase 1: Take this printer apart as far as I can while still preserving electrical and mechanical functionality.

  • Phase 2: Bring out the multimeter, oscilloscope, and logic analyzer. Measure motor & sensor electrical behavior and write them down. Learn what I can about how they work. Such knowledge improve the odds I can reuse them later.

  • Phase 3: After I have learned all I can, take it apart the rest of the way.

Endgame: Keep salvaged components with reuse possibilities. Recycle the metal bits, circuit boards goes to e-waste, and plastic goes to landfill.

Onward to phase 1!

This teardown ran far longer than I originally thought it would. Click here to jump to an index of all my teardown notes.