A drybox spool holder for printing with moisture sensitive filaments which can be used:
The drybox has an integrated sealed desiccant compartment. Optional printable tools simplify filling and emptying this compartment.
An electronic humidity sensor is supported, but not required.
Filament can egress at either the top or bottom of the drybox through PTFE tubing attached with a PC4-M10 pass-through fitting.
This drybox supports filament spools with the following dimensions:
- diameter up to 200mm
- width up to 90mm
- hub diameter between 50mm and 75mm
All Use Cases
Everyone will need the core components from this page:
- drybox stand
- drybox top
- fitting plug
- dessicant cap
- sensor plug (not needed it you plan to use a humidity sensor)
- bearing plug (not needed for linear track rewind mechanism)
Stand-Alone, with Filament Buffer, or with Linear Track Rewind Mechanism
If you plan to use the drybox stand-alone, with a filament buffer, or with the linear track rewind mechanism, you will need the following components from this page:
- bearing insert (will need to print two)
Alternatively, the larger diameter cap, shaft, and nut designed by FlamenG can be substituted (bearing inserts listed above are still required).
If you plan to use the linear track rewind mechanism, you will also need to print the large gear and small gear from here.
Previously printed cap, shaft, nut, bearing inserts, large gear, and small gear are 100% compatible. You can simply move these components from your existing multi-mechanism auto-rewind spool holder to this drybox.
Universal or Integrated Spring Hub Rewind Mechanisms
You will need all of the components from Vincent's pages as well as the collar and shaft from here.
Previously printed universal or integrated spring hubs are 100% compatible. Only the shaft will need to be replaced for use in this drybox.
Optional Desiccant Tools
The funnel and bottle adapter from this page make it much easier to load and unload the desiccant compartment. It is recommended that you print one of each.
Prusa MK3 gcode and .3mf files
Print the two gcodes provided on the Prusa community site for a complete new drybox intended to be used stand-alone, with a buffer, or as a linear track mechanism rewinder.
The gcodes will yield a few small scrap parts, depending on your use case. If you do not want to print anything unnecessary, feel free to use the .3mf files and delete the parts you will not need for your intended use.
If you have an existing linear track based rewinder or existing spring hubs, you need to print far fewer parts. Print the "drybox top" gcode from the files section on the Prusa community site linked above, but not the "drybox stand complete" gcode. Instead, print the "drybox stand upgrade" gcode provided in the user print files section.
The drybox has four holes on the bottom which allow it to be mounted to any horizontal surface. The holes are printed closed and must be drilled out if you plan to use them. There are four small dimples on the bottom of the stand which indicate the correct drill locations.
Please note that you will likely need to un-mount the drybox to load and empty desiccant.
This makes mounting less useful, but I wanted to provide the option.
The drybox has two PTFE tubing mounting locations. One of them must have a PFTE fitting installed and the other must be closed with a filament plug.
For these assembly instructions, I am plugging the PTFE location on the stand and will install a fitting in the top.
The plug is tapered and should be inserted until a tight seal is achieved.
These locations are not threaded, but are sized to allow a PC4-M10 fitting to easily cut its own threads.
If you are using an electronic filament sensor, it should be inserted into the top now.
If not, the sensor plug should be used to fill the opening in the top.
The sensor plug must be inserted fully to achieve a tight seal. The flanges on the plug should be flush with the top when properly seated.
A bearing plug must be installed in the stand for any use case except the linear track rewind mechanism. The plug should be installed from the inside of the drybox.
You may need to clean up some loose filament at the top of the hole if the fit is too tight.
If you plan to use the linear track rewind mechanism, a gear assembly needs to be inserted in this location.
Please follow first few steps of these post-printing instructions to correctly assemble the large gear, bearing, and small gear.
Again, the gear assembly must be inserted into the stand from the inside and be seated firmly.
When correctly positioned, the small gear will be roughly centered in the vertical opening of the channel on the outside of the stand.
The outside of the stand has a threaded hole which opens into the interior desiccant compartment.
An optional threaded funnel is available which greatly simplifies loading fresh desiccant into the compartment.
Once the compartment is full, remove the funnel and install the desiccant cap.
At some point in the future, the desiccant will be saturated and need to be removed. A bottle adapter has been provided to aid desiccant removal.
Place the drybox stand on its side and removed the desiccant cap. Screw a standard beverage bottle (PCO1881 threads) onto the adapter and then the adapter onto the stand.
Invert the stand and shake until all of the saturated desiccant has transferred to the bottle.
Removed the adapter from both the stand and bottle and either discard or recycle to desiccant from the bottle.
If you are using the drybox stand-alone, with a buffer, or with the linear track mechanism, you will need to assemble a spool hub.
Instructions for assembling the cap, shaft, nut and bearing inserts can be found in the post-printing instruction of this page.
If you are using spring rewind hubs, instructions for using them with the required custom shaft and collar can be found here.
Note, the photos on the page above show an open stand rather than the enclosed drybox.
complete stand-alone, buffer, or spring rewind hub drybox
completed vertical track rewind mechanism drybox
Finally, I was able to find a spot for gbzh01's filament path number labels as well.