DeCap-It Bottle Cap Opener

This is an aid for uncapping soda bottles with caps around 28-30 mm in diameter. 

Updated with V2 - Improved ergonomics

I reduced the hand-span required to grip the tool. This will allow more strength to be applied or less stress for people with weakened grip.

The original design is now on a second plate should you prefer that.

Looking for more helpers?

Here's my collection of other independent living aids.

Design Considerations

The model is designed to be lightweight and printable. The handles increase in height to aid grip and stability while the length also provides good leverage. 

While not clear from the photos, the span of the handles at the far end from the ring-grip is designed to fit an adult hand so a gentle squeeze should be enough to grip the bottle cap.

Print Considerations
 

As the handle is rounded underneath (improved ergonomics) so this presents a smaller contact patch with the build plate. Models like this can be prone to warping - If you find the print warps (lifts at either end before the print completes), try a 5 mm brim under the Process Global settings: 

• Others > Brim type: Outer brim
• Brim width: 5 mm
• Brim-object gap 0.1 mm

Plus all the usual precautions, like dry filament, disable any aux fan and keep drafts away, preheat the bed for longer than normal, use that spot on your print bed you know to be less warp prone, clean your build plate or use a better one ( Bambu Cool Plate SuperTack PEI   ) etc. Even though a warped print will function well, aesthetics matter :)

Grip Strength

If the grip is too stiff, you can reduce the Process Global > Sparse infill density - from 20 to 15 or 10%. This will make the ring-grip that flexes softer. Similarly PET-G will be less stiff than PLA.

Materials and longevity - the seduction of the empty squeeze

When used as intended - a bottle cap is in the ring-grip - the handles won't compress than a 5-10 mm to grip the cap. When the ring-grip is empty you can squeeze handles so they touch - but fidget tool this is not. If you do this with PLA it will eventually fatigue and likely crack somewhere at the apex of the ring-grip. A filament with better durability in this application if you have it - PETG HF. 

Scaling - Measure Twice Print Once

You can press the head onto the cap if it's a little too tight - but the wisest course is to measure your cap and scale it with the X/Y scaling if needed. The ring grip is 30 mm in diameter, so:

Calculation = ( Cap size in mm / 30 ) * 100 = Scaling factor

Example: ( 31 / 30 ) * 100  = 103.33

Deselect uniform scale and apply the scaling factor to X and Y only.