These Black HDPE CNC cut blocks give your rudders the precision movement you need. The pivot hole is 5/16" with 3/16" mounting holes on a 3/4" spacing. The mounting holes are offset to keep the block above a 1" or 7/8" rudder mounting tube. The slave bar blocks are designed for mounting into an angle with flat head flush mount screws.
You are buying 9 blocks, 3 slave and 6 pivot type. Combine with stainless pivot plates.
I can tell you how many DIY hovers I've seen with bolt pins going into a aluminum slave bar or pivot plate. In just a few hours the hole is twice the size of the pin, with the rudders moving 20° before the wheel moves. Driving down the freeway wears them out faster than anything.
Our blocks on stainless bolts last at least 800 hours.