Grip Training Ideas
A gripper can be closed, to practice negatives, by inserting it in a steel pipe that is in a power rack. In the photo the pipe is aluminum, and is out of a keg. The end is bent down, so the gripper just fits in. Keg pipe is extremely thin, but strong. One inch dumbbell pipe also works, but would be harder to bend. Just place the end of the gripper in the pipe, around an inch, and use bodyweight to close it. The spring can be held with the other hand if necessary. A heavy glove is recommended. For photo purposes, this wasn't done. This idea is from jklove41 on The Gripboard and Joe Kinney, The first #4 closer.
Approximately 1" washers can be used as gripper chokers, to start the squeeze at a certain point. I got the washers free from a farmer. The look on his face when I told him what was being charged for nearly the same thing was priceless! They are available at McMaster-Carr. Locally they might be available at hardware stores or farmer supplies. They can be custom made to the desired size with a metal file. I also plan to experiment with the use of hose clamps.
Jar simulators are easy to make out of pvc pipe. Just cut to length and glue on end caps. The caps may not be necessary, if the pvc is very smooth. Drill two holes in the middle and insert rope. Several different sizes can be made for very little money. To take the shoulders out of the movement, support the pipe from a pull-up bar. Old belts work good for this. They are easy to find at the Goodwill. This method or slipping over a pipe, can be used to support wrist rollers.