Intro: Black Ram Hand - MVII (BIG Robot)
Learn Design and Prototyping at Black Ram Industries.
This Black Ram Hand was designed to be BIG and used for Robot costumes. It is entirely 3D printable including the bolts and nuts.
50% larger than the size of the Mark V, its can be attached to your arm for a costume as a Robot. It's size really feels huge when on your arm. It works by flexing your wrist allowing the claw to open and close.
Adjust the claw position to change the opening and closing claw size. Use velcro strips to attach to your wrist and forearm.
Step 1: 3D Printing
You will need to print:
1 x Robot hand
1 x Robot gauntlet
1 x Robot claw slider
1 x Robot tendon
1 x Robot tri-claw
3 x Robot gripper a
3 x Robot gripper b
3 x Robot gripper c
12 x Robot claw bolt a
12 x Robot claw nut
8 x Robot bolt
4 x Robot nut
I tried to design with clearances between components, however different 3D printers will have different tolerances and output. Try to print on the highest resolution possible to ensure that you will get the proper clearances between parts. I recommend that you print the bolts and nuts individually (unless your retraction function works well). This will allow for a well formed threads. It may be tedious but you will get a much better result on your assembly.
Also the FILL Density should be at least 80% on Bolts and Nuts to make them strong and able to handle tension. Other parts can have way less infill and adding more can increase the weight of the claws (I got tired holding it up). If you have stronger materials I would only use them on the bolts and nuts. But check the assembly first because they can be very tight which means that I will have to adjust to give more clearance.