I looked at your first post and just did a quick check out of what I understood. Here's what I am wondering based on your first post.
- Do you have two 6s power modules hooked up in series from each battery to get 12s at your ESC's
- Do you have one 6s power module that has two 6s batteries hooked up in series to act like one 12s battery
- Do you have one 6s power module that has two 6s batteries hooked up in parallel to get 6s at your ESC's?
I put the numbers you listed into a static thrust calculator (http://godolloairport.hu/calc/strc_eng/index.htm) with:
Prop Diameter = 29"
Pitch = 9.5"
CF = 1
No. of Blades = 2
Air temp = 68F
Air density = 1.2045
I got RPMs in 2 ways.
First, I assumed your ESCs are getting a full 12s potential difference:
--> (3.7v Nominal) * (12 cells) * (85kV) = 3552 RPM
This RPM outputs over 25 lbs of static thrust which would be 200+ lbs thrust on an octo.
Second, I assumed your ESCs are only getting 6s. In this case,
--> (3.7v Nominal) * (6 cells) * (85kV) = 1776RPM
This RPM outputs about 7 lbs of static thrust which would be just under 50 lbs of thrust on an octo.
These numbers are based off of nominal voltage, so they are conservative. More info on your power distribution wiring setup from batteries to ESCs would be helpful, as would the weight of your copter but by the sound of it, your ESCs aren't getting the voltage.