Step 1: What you need.
glue-hot glue or anything
weights-stuff thats heavy
hot glue gun
Step 2: Lets start
get your pipe and cut a hole in the side the same size as you camera. for a gopro hero it will be 60/40mm
Step 3: Step 2
you can now start to create the two end caps you can use pipe end caps or make some with balsa like i did to save weight.
just cut some wood to the diameter of the pipe and sand down with the dremel to flush with end and glue in place
Step 4: Step 3
Step 5: Step 4
once done you can glue in place.
Step 6: Step 5 balancing the gimabl
Step 7: Step 6
Step 8: Step 7
look at pics for better understanding.