Week 15: Applications and Implications
5.13.2015 - 5.19.2015
Lecture Notes:
Homework:
- Propose a final project that integrates the range of
fabrication subjects covered in previous weeks. Address
questions covering the technical, fabrication, scheduling, and
budgetary issues.
Resources:
Project:
After weighing the technical challenges of the conceptual final project I proposed during week 1 of Fab Academy as well as the usefulness of the project, its potential cost, and topics covered in later weekly assignments, I have decided to revise my final project. My modified project will continue to use a vacuum as an essential element of its design as it was in my week 1 proposal.What will it do?
My revised project will be a modular, inexpensive, medium-large format vacuum former for the fabrication of large scale plastic parts. Vacuum table modules will enable the vacuum surface to expand to accommodate assorted part sizes and after forming the modules can be disassembled and stored in a small footprint.
Who's done what beforehand?
A cursory online survey of inexpensive vacuum formers generally yielded small scale ( ~0.1 m^2), portable, one-piece, table top machines aimed at small volume / hobby fabrication with a cost on the order of 10^3 USD. Numerous do-it-yourself vacuum former plans and how-tos are available online but tend to be a similar scale and/or poorly constructed using improvised parts and methods with an emphasis on optimizing cost (~10^2 USD). Entry level commercial vacuum formers with forming areas approaching 1 m^2 were found to cost between 10^4 and 10^5 USD.
What materials and components will be required and where will they come from?
Major components will include the vacuum table segments, a frame for the plastic sheet, a structure to support the heat lamps and potentially a reflector. Smaller components will include one-way valves and an electronic control system. Locally sourced materials will include engineered wood sheets, wood sealers and glues, assorted electrical components and mechanical hardware. Materials sourced online will include the vacuum blower, heat lamps, potentially other electrical components, and plastic sheet material.
How much will they cost?
The preliminary budget for this project is estimated at roughly $500 USD.
What parts and systems will be made?
- Segmented vacuum table frame, 3D printed one way check valves, lighting control system, vacuum control system (optional), adjustable/collapsible lamp and reflector structure, frame structure
What processes will be used?
- Milling - Large Scale: Principal vacuum former frame
- Milling - Small Scale: Circuit boards
- 3D printing: One-way valves
- Laser Cutting: One-way valve components
- Molding and Casting: Potential hinge components
- Composite: Potential structure components
What tasks need to be completed?
- Scaling components & sourcing materials
- Identification / Evaluation of vacuum forming plastics
- Vacuum table segment proof of concept
- One-way valve design
- Lamp control system design
- Vacuum control system design (optional)
- Frame design
What questions need to be answered?
- Distribution, density, placement, and control of heating
system and its affect on plastic behavior
What is the schedule?
- 5/20 - 5/25: Table segment development, Valve design
and printing, Sourcing Materials and Parts
- 5/25 - 5/31: Vacuum Control System, Table testing,
Lighting control development, Lighting structure design, Frame
Development
- 6/1 - 6/7: Lighting control testing, Frame and Lighting Structure testing, Vacuum Forming Testing
- 6/7 - 6/10: Troubleshooting, Presentation
- Note: Final project deadline later rescheduled for
6/24/15
How will it be evaluated?
- Assembly and Sealing - table segments, valve seals
- Vacuum and Heat Distributions - plastic behavior, physical
part appearance
- Repeatability - heat control system and fixture