Reclaimable Circuit Assembly Process
about 1 year ago by ShaneOberloier
Which problem are you trying to solve?
There will be 92 billion pounds of e-waste generated in 2017 alone. The waste can be hard to process, making recycling
an expensive ordeal.
How are you going to solve the problem?
By eliminating the need for solder. Instead, thermoform a plastic sheet under vacuum around the board, and seal it. To
recycle, remove the plastic and dump out the parts. Copper can be scraped off.
What is the impact of your project?
Drastically simplifying the recycling process will make inevitable e-waste easier to recycle. It will also yield fully
reusable parts. Reduce costs of prototype iterations, as parts can be reused.
How can the project be manufactured in the OpenLab?
The thermoforming machine must be milled or cut from metal in order to endure high temperatures. Some components to the
machine may be 3D printed. Test boards may be milled.
Describe your project in detail
The project is to define and create all necessary apparatuses to make a fully reclaimable circuit board. To start, a
relatively simple SMD circuit (perhaps a simple 555 timer blink circuit) will be designed. The board will be adjusted to
include holes to insure sufficient vacuum distribution. This board can be milled in the OpenLab, as multiple iterations
may be needed. The circuit-thermoformer, or “Circuit Bagger” will somewhat resemble an electric cooking grill.
Nichrome wire will be energized at the top and bottom of the machine heating up plastic sheets. The board will be placed
on the vacuum fixture, and the vacuum will be enabled, pulling the pliable bottom layer of the bag and creating a vacuum
at part locations (effectively holding the parts in place to prevent shifting). The parts can then be placed on the
board. Glue can be placed around connectors and heat-sinks. Finally, the top layer can be lowered onto the board, and
the vacuum will tightly form around the components, holding them tight against the board. The bag can then be cooled and
removed from the apparatus. Connectors and Heat-sinks can then be exposed from the bag. Some experimentation must go
into this process. The minimum vacuum draw and optimal heating temperatures must be obtained. Also, various types of
plastic may need to be tested (Styrene, PETG, etc). Lastly, a good method to apply and remove vacuum must be
In terms of manufacturing at the FabLab, an aluminum enclosure (can be reasonably small) must be cut and
folded. The two halves of the enclosure will be fastened together with a hinging system. Handles for the system can be
cut from any common wood. Then, NiChrome wire will be weaved along the top and bottom part of the enclosure. The wire
will be connected to a power supply with a switch in series. Fixtures must be made for holding the circuit board and
plastic sheets in place (as pictured in the model). These can be milled from aluminum as well. Lastly a vacuum tube
opening must be custom made (perhaps milled from aluminum) to properly distribute and draw the vacuum. The circuit
boards being tested can be milled at the FabLab (given the CNC mill has sufficient precision. If not, I can acquire them
before visiting the FabLab.
(PLEASE SEE THE ATTACHED PDF FOR A CONDENSED DESCRIPTION OF THIS PROCESS)