Accelerometer, that tiny workhorse

The accelerometer chip (1 x 1 cm)

The accelerometer chip (1 x 1 cm)

Accelerometers are wondrous little devices that offer boundless possibilities… as soon as you figure out a need for them.

For some time now, I have been thinking about a filament break detector for 3D printing. Filament comes in spools of 400m (1 kilogram) and they are usually hung on racks on which they rotate. The filament is fed to the printer via a small stepper motor turning a grooved feed wheel. If the filament breaks, or the feed wheel eats a notch into the filament, it will no longer enter the extruder, and the print fails. Usually the filament wire breaks if it has been exposed to air humidity for a long period – it is hygroscopic and becomes brittle.

The printers are not aware of the filament feed. There is no detector for smooth feed, and consequently any hitch in feed will fail the print. I have thought of making an optoelectronic feed detector that would shine a light on the filament spool and detect its movement, but that would require a striped disc to be attached to the spool, as well as the actual reading device installed on the rack. Then I thought of a mechanical device that would ride on the filament itself and detect its movement via rotating discs, but that soon turned out to be too complex. (more…)

Assembling a CoLiDo DIY 3D printer, part 1

Main parts

Main parts

As most of you know, I am not an engineer, despite my lofty ambitions of tinkering with all sorts of things.

So, the other day Jouko Lehtomäki from Suomen 3D-ratkaisut, the partner company of my university Haaga-Helia, brought us a brand new CoLiDo DIY printer in a crate. He said it’d be a piece of cake to assemble, and asked me to film a timelapse of the build. I fended off the task until one day I had no choice, I had to print something in PLA real quick, and the packed printer was the only one available. (more…)