Bonus device -
I also have a little bonus invention for monitoring your filament coils while they are in Zip-Lock-Bags - here is the SpoolCheck sensor.
Please let me know if you make one - thanks.
3d model print parameters
Materials can be bought from eBay and made up at home - See blog and video for further details -
For the temperature/Humidity sensor just search eB...ay for 'Mini LCD Celsius Digital Thermometer Hygrometer Temperature Humidity Meter Gauge'
The main component I used for heating is a simple flexible reptile heater - you can find these on eBay for just a few USD - Search for '15*28CM Adjustable Temperature Reptile Heating Heater Mat'