Penn State Printer Head for Extruded Clay

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The Pennsylvania State University (PSU) School of Visual Arts and College of Engineering are currently in development of an open source clay 3D printing head for use on a variety of open source machines. The project was started in the Fall semester of 2015 and is currently being developed by two new teams for the Spring 2016 semester.

This project is still a work in progress with more updates coming soon.


Project Overview

The ever growing field of 3D printing, more specifically open source 3D printers, caused the PSU School of Visual Arts to have interest in investigated 3D printing as a medium for artists and designers. The ability to print 3D objects in a variety of mediums and the ability to create the 3D printer itself opened up a plethora of design potentials.

The School of Visual Arts soon decided to attempt 3D printing in clay, though not many open source options existed. The School enlisted the help of the College of Engineering and sponsored a Capstone Design Project for the Engineering seniors. The seniors represented every type of engineering at Penn State.

Previous projects of this type typically attempt to use 3D clay printing to print hollow objects such as vases and glasses. The attempts of this project are to be able to print objects similar to those printed in plastic. This involves overhangs and infills that are not typically attempted in clay due to its consistency and inability to harden as it the layers are made.

Phase I, Fall 2015

Phase I consisted of a single team of industrial and mechanical engineers. A preliminary design consisting of a 3D printed head with a PVC pipe pneumatic device was constructed. The pneumatic device used a plunger with compressed air behind it to force clay down a tube and into the printer head. An auger, attached to a stepper motor, was used to stop the flow of clay through the nozzle and also assist in feeding the clay through the nozzle.

The initial design proved to be quite effective with print quality being acceptable but not great. The printer head design was problematic and prone to cracking after three to four prints, though.

The Fall 2015 team project proved that printing in clay was feasible but did not have the time nor resources to further the research into this field. The project focused and continues to focus on prints more similar to that of those done in plastic.

Phase II, Spring 2016

The second phase of the extruded clay printer head is a continuation on the foundations formed by the Fall 2015 group. The second phase began with improvements on the design. The mechanical engineering team focused on most of the design aspects with a key goal to replace the, then current, pneumatic extrusion head with a mechanical feed utilizing a stepper motor. The industrial engineering team focused on designing experimental procedures to fine tune the print settings for after most of the design and build work was complete.

Both teams, early in the semester, constructed a Prusa i3 printer kit to familiarize group members, additional, with 3D printers. The Prusa i3 is being used as a printer for the clay head.

Design

The initial design, and the one with the most print time, was the pneumatic system. This system involved a clay tube made of PVC pipe with cemented fittings. The system was loaded in through the back where a threaded cap with teflon tape was used to make a seal. The cap had a brass fitting for the connection of the air compressor. With soft, not watery, clay approximately 95 psi was required for reliable extrusion.

Pictures of this system are coming soon.

The improved design involves a large stepper motor with a plunger that mechanically extrudes the clay. This system has not yet been tested to print but does reliable extrude clay.

Pictures and updates are coming soon.