This is an external spool holder designed to interface with the Dremel Idea Builder 3D Printer. It may also work with the Flashforge Dreamer and the Flashforge Inventor. In order to complete this project, you will require a 5/8 inch round wood dowel of desired length and four metric M3 x 0.5 x 20mm socket head cap screws.
The external spool holder can be screwed in the existing upper corner screw holes of any of the three sides of the 3D printer (left, right, and back) by removing the existing screws and replacing them with longer screws. Alternatively, the external spool holder can be mounted on the wall using appropriate hardware.
Step 1: Measurements
I measured the hole diameter and distance between the screw holes located on the upper corners of the sides of the Dremel Idea Builder 3D Printer so that the spool holder could properly interface with the printer. I measured the dimensions of a socket head cap screw so that it could be embedded into the mounting plate. I measured the outer diameter of the largest filament spool that I owned so that different filament spool sizes could be supported. I measured the diameter of a round wood dowel I owned.
Step 2: Initial Designs
I drew a basic 2D profile of one spool holder bracket, extruded it to a reasonable thickness, and projected a canvass on the mounting plate so that I could draw the screw holes. Having some knowledge of the printing characteristics of my 3D printer, I estimated the required tolerances and ensured that I oriented my model so that it could print without added supports. In my original version, I embedded the hex nut so that a wrench would not be required to tighten the screw and nut. Unfortunately, I found that there was insufficient clearance inside the printer to use a screw driver to secure the cap screw from the inside. I therefore changed the design to have the nuts inside. This took longer than it should have as I had not saved some of the guidelines in my 2D sketch; I had to recreate some areas from scratch.
Step 3: Prototype Prints
I made three prototype/partial prints in order to verify the fit of specific areas of the spool holder. The first trials were close but unsuccessful so I had to tweak the designed tolerances. I also had to correct some warping issues caused by originally not having a 3D printer equipped with a heated bed and printing a long model. I ended up using a raft for my prints and getting a decent fit.
Step 4: Final Print and Assembly
I ordered four metric M3 x 0.5 x 20mm socket head cap screws to get an optimum fit with the printer. Once the new screws arrived, I used them instead of the screws that came preinstalled on the printer and enjoyed a great filament spool holder.