Forearm/Wrist/Finger workout

So today was my first attempt at a wrist and finger workout. My left forearm is cramping up, hopefully that means I did well. Workout:
Hang from pullup bar (feet touching ground, but providing minimal support): 60 seconds -> try for 75
pinch grip between thumb and tips of fingers, two 2.5 pound plates: 60 seconds -> go for 2.5 and 5 pounds
dumbbell finger roll up (stand with dumbbell at side, let dumbbell roll down so only the tips of fingers support it, curl fingers until dumbbell is in palm of hand): 50 repetitions with 15 pound dumbbell -> try for 25 pound dumbbell
dumbbell wrist-up, seated with forearm resting on thigh: 21 repetitions with 15 pound dumbbell -> try for 25 pound dumbbell
dumbbell rear wrist-up, stand with dumbbell down behind back and lift wrist to the back: 50 repetitions with 15 pound dumbbell -> try for 25 pound dumbbell
dumbbell lift to outside, stand with dumbbell and all weight on one side (5 pounds on the 5 pound bar) and grip the other end, and lower and raise the weight: 16 repetitions -> try for 20+
dumbbell lift to inside, 21 repetitions -> raise the resistance
dumbbell pinch, 2.5 pounds and 5 pounds: 25 seconds, try for more
reverse curls, 15 pound dumbbells, 27 repetitions -> raise the resistance.
pullup bar hang, feet touching the ground but providing minimal support: 40 seconds, try for more.

So... we'll see how this works for me. In terms of vanity, I want to bulk up my left forearm. It's very skinny. In terms of useful strength, my left hand grip strength dramatically trails my right hand and I'd like the narrow the gap. It would even be cool if my shorter left arm had a monster grip even stronger than the right, but I would be pleased with near parity. I'd also like stronger wrists to protect myself during dumbbell lifts and be more useful moving furniture, twisting stuff, and so forth.

12/12 - second wrist workout. I doubt a 1.25 inch wide dowel, put a hole in it and a rope through it, and hung a 10 pound weight. I thought it would be easy, but damn is it hard.
Wrist curl up-> 1 repetition (all the way up and all the way down) w/10 pounds with a forward and down curl, about half a repetition with 10 pounds with a back towards me and down curl.
Bar hang: 65 seconds
pinch grip, 7.5 pounds: 45 seconds -> same weight
dumbbell finger roll-up, 25 pounds: 19 repetitions -> same weight
dumbbell wrist up - wrists were fried from wrist curl up, 17 repetitions with 15 pounds, stay.
standing rear dumbbell wrist up: 21 repetitions with 25 pounds -> same weight
dumbbell outside lift, weight on one side, 5 pounds: 21 repetitions -> same weight
dumbbell inside lift, weight on one side, 7.5 pounds: 17 repetitions but range of motion may be less, drop back to 5 pounds.
dumbbell pinch, 7.5 pounds: 27 seconds
reverse curl, 20 pounds: 17 repetitions. Watch right forearm, can't do a 'true' reverse curl with that weight, have it partly turned to use regular biceps. Fix it.
pullup bar hang: 25 seconds
wrist curl up: about half a repetition going forward and done.