Changes in Pogress - TechforTrade/Thunderhead-Filament-Extruder GitHub Wiki

Thunderboard - A new electronics board has been designed. It has been tested on the benchtop but not with the machine. This should simplify the electronics instalation greatly.

Electronics enclosures - Previously, the high and low voltage electronics were housed in the same box. There were a number of interference issues especially with the keypad and LCD. We are moving towards using two enclosures - one for the high voltage components and one for the low. They have not been designed yet. The controller box in the old design will no longer be used.

Drying hopper - A drying hopper has been designed and somewhat tested. The results are good. Unfortunately the designs are not documented yet. Check out the GrabCAD page for the Solidworks files. The drying hopper takes the place of the starve feeder which was made from the vibratory conveyor and balance.

Diameter Sensors - Our laser based non-contact diameter sensor has been problematic and we have decided to stop development on it for the time being. We are now switching to a computer vision based diameter sensor pioneered by Joshua Pearce's group at Michigan Tech. It is uses a Raspberry Pi and a pi camera. It is still in development phase, but it looks promising as we have measured diameters down to 0.02mm repeatably. Use of a Raspberry Pi may also open up the door to create a GUI for the machine and enable control/diagnostics over the internet.

Water Bath - We are looking into the possibility of air cooling the filament which will reduce cost and make diameter measurements near the nozzle easier. Experimentation is needed.

Extruder Body - we have made some slight changes to the extruder body so that most or all of the plumbing parts are not needed. We have found that the plumbing parts are not uniform and frequently low quality and don't align well - especially floor flanges. Changes not documented yet.

Spooler - Early attempts at a spooler were not sufficient. This is a needed component. It should have its own control electronics and interface with the rest of the machine via IIC. It must not overpower the outfeed and should evenly distribute filament across the spool.

Chopper - Here's a link to our CAD files for the chopper. It isn't documented yet. Chopper Link

Drying Box - Here's a link to our CAD files for the drying box. It isn't documented yet. Drying Box Link. The electronics board needs to be redesigned because the power traces weren't large enough. The current version we have in use is just using a thermostat instead of a microcontroller.