20x20 to 16x16 mm adapter for FC/ESC

thingiverse

Since the space between 20x20 and 16x16 mount holes is extremely tight, I employed this solution to fit a 16x16 ESC onto a 20x20 copter. Print in TPU. This is a critical step, although you can likely use glue instead with PLA etc. Position the adapter on the 20x20 mounting holes and push a M2x6 screw through the mounting hole and into the outer hole until it sits flush. This requires some force, which is intentional. Next, place the ESC/FC on the inner holes and push either a M2x4 screw through from above, or trim the thread of a male-female m2 standoff slightly (so the thread is approximately 4mm) and push that through the mounting holes, then position the FC on top of standoffs. This makes it relatively low-profile, providing some softmounting too.