Note: Experimental and work in progress.

The aim is to print functional and strong parts with high flowrate and with reasonable quality at the same time.

Github Mirror, project Homepage

DDPrint FDM firmware: https://github.com/ErwinRieger/ddprint.

Project homepage: http://www.ibrieger.de/close_the_loop_for_e.html.

Video: https://youtu.be/1Kbl9AZd10Y.

How to do it?

  • Add a flowrate sensor to your machine.
  • Add firmware support for this flowrate sensor: ddprint

The flowrate sensor

The flowrate sensor is used to measure the speed of the filament after it exits the feeder. Using the diameter of the filament, we can calculate the flowrate from the filament speed.

Note:The current form will only work with bowden type printers, obviously there is no space for it on a direct drive setup.

The sensor consists of the following parts:

  • A Bourns EMS22AFS incremental sensor.
  • A 3d printed body: feedsensor.stl, note: this model contains some custom supports.
  • Some additional parts like a teflon tube and a pneumatic connector to connect the bowden tube of the printer.
Todo:add video with sensor in action.

Other usages, advantages of the flowrate sensor

Todo:...
  • Helps to avoid underextrusion or filament grinding in many cases: hotend to cold, first layer problems and so on.
  • Allows to record the tempearature/flowrate profile a filament by extruding some filament at varying speeds. This data is the base for the AutoTemp algorithm.
  • Auto-calibrate the feeder.

Result

Print reliable with high flowrates while still getting good quality.

Video: https://youtu.be/1Kbl9AZd10Y.