A functional claw, ready to print! This is an old claw model for First Competition robotics. I've since then came up with a better design, but will not post yet for competitive reasons.
You do not have to use the printed pins to secure each finger. Bolts or stock aluminum or steel will work better. Use the donuts on the top to attach strings to, and the cylinders on the back of the fingers to guide the string. Attach the strings to a motor to control them. The donuts on the inside of the fingers attach to the donuts on the base plate via spring or rubber band. This acts as an automatic retention system.
30-60% infil recommended.
Attach all 4 strings (one string per finger) to a motor mount of your choice to automate the opening and closing of the claw. Modify as needed. Enjoy!