After watching divers try some makeshift ways to seal their KISS Spirit and Sidewinder partially used sorb containers, I created some caps for this purpose.
However I quickly realized, while these did reasonable job of sealing the scrubber canister, it only worked if the canister was stationary. If the canister was placed in a vehicle for example, and tipped over while in transit, the sorb would spill inside the canister. This of course not only makes a mess, but ruins the sorb bed, and renders the canister unusable.
The solution was an easy one: come up with a cap that held the upper screen in place like the head does. This design has a locking ring identical to the one found on the Spirit/Sidewinder heads, and also uses the same springs for compression on the top scrubber screen.
Here it is for those who wish to build one. This design prints in 2 runs per cap, without support material.
Directions to build
1. Get hardware
Source 4 M3 hex head screws. These can be as short as 8mm or as long as 12mm. 12mm is best. Get a spare head o-ring. Optionally, get 4 head springs from KISS, or you can use the ones existing in your current head.
and print all parts from here.