3D Printing for Metal Components

The goal of the project is to cheap and effective 3d printer which can print metal components, by integrating the technologies present in plastic 3d printing, and MIG welding.

Background
With the technological advances in the field, 3d printing has recently become very popular, but one major drawback to these machines is that they can only print in plastic. Plastic 3d printing has many uses, but there are many applications where, whether due to temperature, high stress, or other reasons, plastic doesn't suffice. There are currently a few metal 3d printers on the market, but they can cost tens or even hundreds of thousands of dollars, putting them out of the price range of many.

Deliverables
A device capable of precisely and effectively printing steel components costing less than $1500.

Specifications

 * Project Specifications (As of 11/3/2016)
 * Print Volume  - 8x8x7 in.
 * Resolution    - 150% of Electrode Size
 * Print Speed   - 100-200 mm/s
 * Electrode Size - .025 in.
 * Plate Thickness- 1/8 - 1/16 in.
 * Input Voltage - 120 V
 * Exterior Temp. - 110 F
 * Cost          - $1500
 * Total Size    - 36x36x36 in.
 * Layer Thickness- 25% of Electrode Size
 * Wire Feed Rate - 40-500 in/min
 * Output Amperage- 10-50 A

Client Interview

 * Wrote a list of questions for our client in order to ascertain the parameters we needed to meet, those we would like to meet, and those we could try for if time permitted.
 * From the answers we were able to compile a list of design parameters to meet.

Lead Instructor and Technical Advisor Meetings

 * Every week we meet with our lead instructor/client to go over the previous week's project and ask any questions we needed answered.
 * Every week we had another meeting for just the team, this is where we discussed the project, and made most of our final team decisions.

Research
To start this project, our team broke into two subsections, the CNC team, responsible for the 3d printer and attached code, and the Welder team, responsible for the welding apparatus and the power supply which drives it.


 * CNC

The CNC team quickly settled on the idea of findng an open-source printer to use rather than designing a system from scratch, and not long after that decided to source our own parts for it rather than buying a kit, so we didn't have to pay for the systems like the bed and the extruder which we weren't going to use. We looked at a variety of open-source printers, but eventually settled on the P3Steel, a steel-framed variant of the Prusa i3.


 * Welder

The first decision we faced was whether to purchase a commercial welder and modify it, or to create one of our own. We eventually settled on creating our own, because our power requirements were so different from that of a standard welder. We did decide, however, to make use of some parts of a commercial welder, specifically the weld cable, and wire feed system. We will be designing our own circuitry based on a commercially available microcontroller and power supplies, our own gas shielding system, and our own printhead/extruder.