DB's Adjustable Locking Arm

My workbench boom lamp has finally annoyed me enough to find a better one
What I found was more of the same the joints locking with a friction clamp
Swinging the lamp and general vibration always makes them loosen and droop
The ones with with an locking joint ether cost way more than the should or just looked crappy
I also wanted something I can interchange the lamp or where I mount it
So ... Here is my solution and with hardware cost less than $20 and 24hrs to make

I split the 3rd part