High Reliability Fidget OTF Knife

The changes I made to kyle's THA otf knife was the shape of the thumb actuator, and I added a snap-in ledge to top and bottom, so that it would stay closed without screws or glue.

The key to the reliability is:

1. Printing the spring and slide in ABS, this gives the knife better stability, as ABS is less likely to change shape with use, as PLA does. I noticed the slide distorts under pressure, so ABS is better able to resist that distortion, as that distortion makes the slide rub against the blade 

2. I printed the top and bottom with all top surfaces ironed for smoothness, as this affects reliability

3. I printed the blade and slide on a smooth PEI bed, again for smoothness

4. The rubber band only needs to be light band (I used a rubber band from a bunch of asparagus)

5. The snap-in ledge improved kyle's THA otf knife, as it kept the top and bottom closed, kyles knife the top and bottom separate with use

Note:

1. If the blade does not catch every time, try bending the spring slightly to increase catch tension 

2. lightly lubing the blade and slide may help also 

Printing details:

• Printed on Bambu Lab X1 Carbon
• Printed on smooth and textured PEI bed
• Used generic ABS and PLA
• Printed parts with 3mm brim for better bed adhesion (parts must be dead flat)
• Printed with brim-object gap of 0.18, for ease of removal
• Printed all top surfaces with ironing
• Top and bottom were printed on textured side for aesthetics
• Blade, spring and slide were printed on smooth side to minimise friction

1. Changed thumb actuator shape
2. Added snap-in ledge to top and bottom