For an overview of the build and a video all about it - please take a look at my Blog post here - https://richrap.blogspot.co.uk/2018/02/diy-heated-drybox-for-3d-printing.html 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. https://youtu.be/RvTTQqqWIWA Please let me know if you make one - thanks.