Exacto Knife Box Inserts

When I was around 10 years old, I got this set of X-ACTO® knives with assorted blades in a very nice wooden box with an absolutely horrendous plastic insert.  Many, many, many (too many) years later, I created a new insert. Some of the features include:

• Holds small, medium, and large X-ACTO to knife handles.

• Handles are held in place with a magnet.  The small and medium handles can be removed by pressing on the end of the handle, which pops up the blade end of the knife.  The large handle can be grabbed by the blade tightening collet and pulled up.

• Blades are held in by magnets and can be removed by putting a fingernail under the blade in the groove next to the magnet.

• Lower insert includes space for one each small, medium, and large handles with a blade.

• One upper insert has space for 5 blades up to 11 mm (13/23") wide and one blade up to 13 mm (1/2") wide, a blister pack of spare blades, and assorted blades/items in a large 62 x 30 mm (1-13/32" x 1-3/16") area with four magnets.

• A second upper insert has space for the 5 blades listed above, the blister pack of spare blades, and two spaces for tubes of spare blades 65 x 13 mm (2.5" x 0.5"), like the tubes from Excel Blades.

• Fits in a box whose inside dimensions are approximately 155 x 59 mm (6-3/32" x 2-5/16")

Printing and building notes:

• The box is designed for 5 mm x 5 mm cylindrical magnets (the same one used in the Core One Frame design).  The spare blade tube holders use 5 mm x 3 mm magnets.

• Due to variations in box sizing, the upper insert may need glue or double-sided tape to stay in place.

• The magnet on the rightmost blade slot may need glue to keep from falling out (I actually used a bit of cellophane tape around the outside of the magnet to get it to friction-fit into the hole).  Other magnets should press fit into their slots.

• The magnets in the lower insert are designed to sit 1 mm below the surface so they don't hold the knife blades too strongly and make the knives difficult to remove.

• The magnets holding the blades are designed to sit 1 mm above the surface and be in contact with the blade, to hold the blade tightly but allow space to get a fingernail under the blade to remove it from the holder.

• The 3MF file includes configuration for printing in PETG, but the model also printed fine using PLA.

I have no association or affiliation with the X-ACTO company, nor is this model endorsed by them.

7-Apr-2026: Updated with second upper insert.