"Regular pencils and golf pencils- no good. The wood swells up, the lead then is no longer supported, it breaks and falls out.Those other regular pencils that LOOK like wood, but aren’t- leads too soft and doesn’t show up on the paper.All graphite pencils – my old favorite, but keeping them sharp is an issue, and the plastic heat shrink like covers don’t agree with mere mortal pencil sharpeners. You need those counter mounted ones from Mrs. Krabappel’s classroom, which chew up the graphite. Also fragile and tend to snap in half.Mechanical pencils - work great the first time, don’t work at all the second time. If liberally coated with WD-40 before and after each dive, you might get 3-4 dives out of them before they rust to the point of being non-functional. True of both the click-end and twist point type. Do you know of any all plastic ones?Pop-a-point pencils – these seem to be the winner so far, but have the fatal flaw of losing one nib causing entire system failure. Also difficult to find."Do you happen to have any advice on something else? Is there some mythical soviet-era underwater pen? Some mil-spec tactical pen that is waterproof down to 100 M? Although both of those would be out since I need a couple dozen of them at least. There are a variety of scuba diver marketed pencil contraptions (including etch-a-sketch ones) that are great if you are writing something like “cool fish!” in giant letters, but are next to useless when one needs legible small writing."
This question has me stumped, so can any of you help Chris out?