Filament stoppages are one of the biggest hurdles coming in the way of 3D printing. Chris Robertson is an independent inventor who has devised a technique to overcome this problem.

Filament stoppages occur due to a variety of problems like the jammed extruder, grinding extruder gear, stalled extruder motor, clogged nozzle, or an empty filament spool. When the filament stops running, there is a risk of the print being ruined which wastes both resources and time. Robertson has designed what is known as a Filament Roller which detects the filament movement using infrared. If it stops a 100 dB alarm is raised which stops the printing process using a switch signal. The user can then detect the error and fix it.

The Filament Roller is superior to other similar devices on a variety of grounds. Other filament monitors use a mechanical rotary switch. The switch becomes worn and needs periodic replacement whereas the Filament Roller will last as long as the printer itself. The filament roller is durable and cost of the product is also affordable. Other filament monitors also require an additional tensioner to hold the filament to detect when it is stopped. They increase friction in this process, and the extra stress ends up causing more filament stoppages.

The Filament Roller is easy to set up and modify. It runs off a 24-volt external power supply or can hook up directly to the power source of the 3D printer itself. The users can easily adjust the sensor according to the speed of the printer and also adjust the alarm delay. Robertson claims that his product is designed to be equally suitable for hobbyists, amateur printers, creatives, or people running huge process. The Filament Roller has a flashing LED so its own functioning can be checked easily. From Raspberry Pi to OctoPrint to self-built RepRap systems, the filament roller can be used with multiple devices.