It would be best if you could upload a bin file of a takeoff attempt.
My guess is that there is something going on with your thrust curve.
Are you able to test thrust of each motor/esc/blade combination on the bench?
Assume 5 thrust points, ( 15, 30, 45 and 80% ) and take notes to compare each motor. If they are like the same, definitely it is not an HW problem ( assuming that all the connections are solid )
If you don’t have a thrust stand, an chinese luggage scale would do the job. just hold an arm under the motor being tested with the scale and measure the lift force. You will need to work on that… It is not easy ( BE CAREFUL!! )
I recommend you go through this way instead of trying to rebuild everything from the scratch.
I have similar problems with T-motor 40A ESC. I found out that ESC dont like state of PWMoutput of ardupilot in disarm mode by safety switch ( I thing no signal from Pixhawk). When I use PX4 Firmware is possible to set output value in disarm state.
For arducopter I disable safety switch and i start working OK, or if you have separate power supply for motors and pixhawk(like me) you can first pres safety switch and then connect power to ESC.
CN
Hi i recently built a drone and it will not take off it will spool up then once i get to 75% throttle not only does it not even start lifting off the ground my flight controller starts flashing yellow and red and i dont know what that means i have tried everything of my knowledge (which isnt very much) any help would be greatly appreciated
Open a new post in Arducopoter 4.0. And you will need to give a lot more detail than that. What errors are shown in Mission planner for instance when it’s connected.