It appears most blades were never used!
VINTAGE X-ACTO 3 KNIFE & 13 Blades WOOD CARVING SET IN Fitted WOOD BOX COMPLETE
Precision Hobby Knife Set with 3 Handles and 13 Blades - X-Acto Style
X-Acto Deluxe Wood Carving Set
Why You Should Buy a Marking Knife
My first proper little machining project made during my free time in my university's machine shop, a brass x-acto knife handle. Thoughts? I'm stoked with it. : r/Machinists
X-ACTO Compression Basic Knife Set, 3 Knives, 13 Blades, Soft Carry Case, 17 Count & X-ACTO 11 Classic Fine Point Replacement Blades, 40 Count : Arts, Crafts & Sewing
X-Acto, EPIX5082, Basic Knife Chest, 1 Each
X-ACTO Products - X-ACTO - Knife Set, 3 Knives, 10 Blades, Carrying Case - Sold As 1 Each - Three styles with assorted blades that fit all three knives.
Excel Knives and Blades
Knife & Tool Sets @ Raw Materials Art Supplies
My first proper little machining project made during my free time in my university's machine shop, a brass x-acto knife handle. Thoughts? I'm stoked with it. : r/Machinists
For the discriminating woodworker, this set includes high quality tools. It is a complete set for virtually every woodworking requirement. Included
X-Acto Deluxe Wood Carving Set
Vintage X-acto Knife Kit