Only one of the gyms I workout at has a piece of equipment specifically designed to work your grip and forearms. It is easier and safer to use than some other method of working one's grip. My grip is shit however, carpel tunnel and arthritis has really fucked it up. This is one of the main reasons I favor machines as opposed to free weights. I never know when I'll get a severe cramp that causes me to lose my grip.
Thanks for stopping by, Prime.
Hand problems can certainly derail training. I have had trigger finger problems in the past. I have a slight trigger finger now which I'm careful with.
I don't have any sure solutions.
I'm sure you are aware of the following but I'll post them anyway.
This exercise is often suggested using a rubberband to work the opposing muscles of the hand which are often neglected.

Another exercise is to take a thin towel or rag (a golf towel works well) and using only your fingers, gather it up into your hand. Repeat until you feel a burn.
Do 3-4 times a week but not everyday. This can also be done with newspaper but who still gets the newspaper? I took a thin kitchen towel and cut it in half.
This really gets the blood into your hand and forearm.
Just squeezing a soft towel is a good hand exercise too. Wringing/twisting a towel also.