See my original version for regular mill holders here:
https://www.printables.com/model/271443-r8-mill-holder-tray
This is a modification of the above linked drawer storage tray for Weldon type mill holders for R8 taper. I bought a holder for ¾" shank mills, mostly to use with a slitting saw arbor, but it was too big to fit the normal tray. I made the tray bigger, and added additional material to support the enlarged end. This fits my ¾" shank end mill holder perfectly, but I don't know whether or not it will fit yours.
The design features 4 magnets on the base to hold the tray in place, and one at the tail end of the taper to hold the taper in the tray. It retains the hoop over the tail end, which was to prevent tipping out in the original, but in this version it really only is there to hold the retention magnet. [EDIT: See updated version below, without hoop] Each tray requires 5 10mm x 3mm round N48 neodymium magnets. They can be glued in place, but I have found it to not be necessary since the holes are sized to provide a snug press fit. I have found the trays retain their position in the drawer, and retain the mill holders well unless the drawer is slammed open or shut.
The tray is designed in Imperial units because those are the units of the R8 taper specification, and it was just easier to measure the metric magnets in inches than to try to do the taper in mm, so you'll have to keep that in mind when opening the model in your slicer. This should be printed vertically on its tail. [EDIT: 1.0 version only must print vertically] I used PETG for this with good results. Other materials may work, but I don't see a lot of point, and you may have to adjust for different shrinkage to maintain fit.
UPDATED 25JUL2023:
I decided to try a version of this without the “hoop” around the tail end, which isn't necessary for this tray like it was for the earlier model it was derived from. Turns out I like this one better…. I also added some peak to the hole for the magnet at the tail, so that it will print properly with the tray printed flat instead of vertically. It can now be printed either way, but I found that it printed a little faster flat.
Both versions should be printed at a 0.2mm layer height for best results.
The author marked this model as their own original creation.