Large 3D printing filament dryer and storage box, with over the top design specs:

• Max drying temperature of 120°C 🔥
• Air-tight construction (not while drying)
• Ability to hold 4×1kg or 6×700g or 1×2.5kg spools

• 🚚 Ammunition Box 47x21x37cm (NATO size 3)
• 🚚 PTC heater 22V 400W 120x50mm
• ❔ Thermostat (ETC-961? REX-C100? ITC-100VH?)
• ❔ High temperature fan (convection fan for the oven?)
• 🚚 Steel threaded rivets M10 ≥6pcs.
• ✔️ PTFE tubing & couplers
• ❔ Alarm light and buzzer
• ✔️ Power switch
• ❔ AC IEC socket
• ✔️ Wire crimper and supplies
• ❔ Alternative gasket material

Goal is to have it for a price of a cheapest commercial dual-spool drybox. At the time of writing Creality Space Pi can be found on Aliexpress for 366zł.

I was able to get surplus ammunition boxes for 100zł (~$25).

I'm not sure what the best heating solution is yet. PTC heater with automatic shutoff at 150°C and with higher power then other commercial dryers have seems safe. Safer then disassembling a hair dryer. It might be under-powered, we will see. It was cheap, at 52zł.

Threaded rivets will make installing ports for printing directly from the box very easy. I got both M4 and M10 from Aliexpress for ~30zł.

Thermostat should cost <100zł. Same with fan and fan motor.

Spent so far: 182zł.

Researching products designed for convection ovens (termoobieg) and DIY meat smoking (wędzarnia) helped. There are no unsolved issues here, just a lot of integration.

• 2024-03-06 - project started, initial purchase - box i.d. 43.5×37×18.5cm

• Glass visor
• Flament rotation motor
• Humidity sensor (needs to be temperature resistant)
• “IoT” reporting and control
• Load cell for spools
• Klipper/printer integration