Airtight Filament Canister

thingiverse

I experienced issues with humidity entering my filament and causing small pops on the sides of my prints. I realized that when the issue didn't occur with a fresh spool of filament, it was absorbing moisture. The Airtight Filament Canister solves this moisture problem and provides convenient storage. It comes with three cradle designs which allow the filament spool to move freely. The filament is fed through an airtight connection using either 1/4" PTFE or 4mm PTFE tubing. You can use either the 1/4" PTFE connection or the 4mm PTFE connection. The canister is completely airtight except for the small hole in the end of the tubing where the filament exits. The hole is plugged by pushing the end of the tubing into the matching cap. If you want to put your canister on a shelf above the printer, you can install the filament port on the side of the canister near the bottom. There are three versions of the cradle: one piece design for smaller spools, one piece design for larger spools, and an adjustable spool cradle which is better than my original one piece cradle. Between the two cradles, this canister design will support spools from 56mm through 80mm wide. I have a new adjustable spool cradle which is better than my original one piece cradle also presented here. The complete information is here: https://www.thingiverse.com/thing:2394480 I removed the printed port for 0.250" PTFE. I think the purchased ports are better and they are easier to install. You can print this design with a Prusa i3, using PLA, at a temperature of 200C on the extruder and 60C on the bed, with no rafts or supports, and a resolution of 0.1 or 0.2mm and an infill of 40%. To assemble the spool cradle, you may have to clean the holes with an 8 mm drill or a file. The pins have a very small expansion on the end to retain them. If they can't be pushed in, you may have to sand them a small amount. Drill a 3/8" hole if you are using the 10mm PTFE connector and use two layers of Teflon tape to seal the connection. The fitting self threads into the soft plastic. You could probably leave off the Teflon tape and it would also seal fine. To install the filament port, drill a 1/4" hole to one end of the cap and then use a step drill as shown to open it to 1/2". Glue both the filament port and the retaining bushing to the canister cap using Super Glue (for PLA). Push 14-16" of 1/4" PTFE tubing into the open port. Set the cradle in the bottom of the canister and feed the filament from under the spool up through the port, tubing, and to your printer. When you're not using the filament, remove it from the printer and plug the open end of the feed tube into the sealed secondary port. You can also throw a couple bags of desiccant into the bottom of the canister. Your filament will stay nice and dry.