Basic 18650 Case

I downloaded and printed many many 18650 cases, and decided to make one of my own, to address all the flaws that draw me crazy.

So here we go:

- This one does not need unnecessary thick walls, since it does not have a thread that requires fat walls

- I've made the chamber 19.1mm diameter, to accomodate some thicker protected cells, and also for ABS shrinking in mind, since I only print in ABS.

- It's sleek and linear design, perfect to fit the battery and just drop it in the bag, with no unnecessary extremities, lanyard holes or clips

- If you print it in 0.15 or 0.2, the roughness of the layers will keep the cap nice and tight, and in mu case also waterproof. It does not require a thread since the friction keeps the cap on firmly.

- If it happens for you that the cap fits too tight, or that it does not fit at all, just use a little sand paper and roll it a few times around the cap, it will fit perfectly. Try not to force the cap inside if it's too tight, because it w