Really Useful Box Filament Dry Box - Silica Gel Fan Dehydrator

thingiverse

I originally tried to use an Addis Cereal box as a filament dry box when printing, but it was just too small - so I went all out and bought a 19 litre Really Useful Box on Amazon that will hold four rolls of filament (one for printing with and three spares). I filled in the voids in the lid with bathroom silicon sealant to make it air-tight. As it's so much larger and will be opened quite often, I decided I needed active dehydration and made use of two 40x40x20 fans I had in an old computer hard-drive bay cooler and some grills designed to cover a computer drive bay. I chopped up one of the grills and used it between the fan and the filament and another I can use a a lid for the silica gel holder if I want (I prefer the solid lid I've posted here as it forces the air to go through/over the silica beads). I've put hot glue at the bottom of the grills in case and beads make their way through any gaps and I've put a bit on top to hold the fans in place (friction does most of the work for me really though). The holder is just bolted to the side of the case and I've used plastic washers either side that should make it mostly airtight. I printed this https://www.thingiverse.com/thing:2172384 great nut/bolt/gasket combo to allow me to run PTEF tube straight from the drybox into my CR6-SE filament sensor using a modded version that allows PTFE straight into it (check my other things to see it). I ended up screwing nuts onto the PTFE tubing either side of the bolt to stop it coming out and still rotate if it needs to. My filament reel is just on two TUSH bearing spool holders https://www.thingiverse.com/thing:2047554 at the moment and I'll probably print a spacer to make sure it doesn't get pulled into the front of the box (hasn't happened yet). The fans are supposed to be run off 12V and running them from a 5V power bank means they are very low airflow (I've had it plugged in probably 24 hours and the power indicator on the USB powerbank still says it's full. I've got some 5V ones on order from China that will have a higher airflow - but if they drain the battery too fast I'll go back to the 12V ones running at 5V. I'm hoping I can get away with charging the USB power bank once a week. I've posted decent-sized photos in my make. UPDATE: I put in a micro-USB socket onto the outside of the box instead of plugging it into a USB power bank as I got tired of charging the power bank every few days. I have a multi-USB mains socket for my Raspberry Pi anyway, so I ran a lead from that into the new socket (photo attached). UPDATE 2: I printed a spacer for the spool holders that keeps the filament spool 1cm from the side and centred so it won't be pulled into the side of the box.