Revised Leather Strap Cutter

This is a revised model of the “Adjustable Leather Strap Cutter” with several tweaks that hopefully improve the functionality of the tool. 

1. Added a fillet inside the body to prevent leather straps getting stuck during use
2. Added a thumb indentation for better control of tool
3. Fit all components on one plate
4. Added millimeter increments to the measurement indicators
5. Increased the size of the knob cap to provide a tighter fit
6. Increased the height of the cutter stack to accommodate my 9mm blades
7. Changed the bottom plate from a screw-hold to a simple pocket so blades can't fall through

Requires:

• 9mm blade (I'm using 3 segments of Zoid snap knife blades)
• 2pcs M3 nuts
• 1pc M3x15 screw
• 1pc M3x20 screw
• 1pc M6 nut
• 1pc M6x40 bolt with hex head

Assembly:

Components:

(1) long rectangle with numbers
(2) long rectangle without numbers
(3) small flat rectangle with hole
(4) small rectangle with triangle points
(5) knob
(6) knob cap
(7) main body

Steps:

1. Insert an M3 nut into the slot in (1) . Insert the shorter M3 screw into the hole and hand tighten for now, leaving the gap for the blade open.
2. Remove inner support from (5) - you can use the M6 bolt to push it out
3. Insert (4) into (7). The triangles fit into the groove in (7). The side of (4) with the divot should face the top of (7) with the hole. The wider half should face the nut pocket, the narrower half facing the fillet in (7). It takes a small amount of force.
4. Assemble (1) (3) (2) together in a stack, with (1) on top with numbers visible, (3) at the end opposite the blade slot, and (2) on bottom with nut gap accessible. Screw holes should align.
5. Insert M3 nut into remaining pocket in the stack and longer M3 screw into hole; screw down to fix the stack together.
6. Slide the stack into (7). (4) should be at the top against the hole in (7). The flat side of (7) should be where the blade side of the stack is, the rounded side with the screw hole side of the stack.
7. Insert M6 nut into pocket in (7). Insert M6 hex head bolt into the knob (5). Screw bolt into nut, tighten using knob. Place (6) on top of hole in (5).
8. For the blade I use Zoid 9mm snap blades, Olfa probably works as well. Insert into slot in the stack, facing toward the bottom of the handle where the grip is. Tighten in place with the M3 screw.

This video is great for learning how to use and assemble a (non-3d printed) leather strap cutter: 

Tips:

1. Don't overtighten the M6 screw during use or it will push through
2. Don't overtighten the blade holding screw during use or the blade will snap
3. Use needlenose pliers to maneuver the blade into the pocket if you're having trouble