This is my plan which is why i plan to put octoprint on the RPi. I want to get the printer running smoothly for a while before i venture into Klipper with it. The support is too great for it the way it is to do that now.
Cooling is the reason i havent ordered a volcano hot end yet lol. I will wait until you are ready to push them and then follow suit. Tomorrow i will put the Octoprint on it and post up what i see as far as the mesh. Hopefully you will see a smoking gun!
You can try “my” octoprint plugin which makes the terminal easier to read:
I didn’t write it. I only suggested it and then edited it a little. After the boilerplate, it is about 5 lines 
Ok @vicious1 @jeffeb3 here is what the terminal says after a G34 (not sure why i lost the top part but i believe this is all the actual info…)
Z2-Z1=3.9100 Z3-Z2=1.7300 Z3-Z1=2.1800
G34 Iteration: 2
Z2-Z1=0.5200 Z3-Z2=0.2600 Z3-Z1=0.2600
G34 Iteration: 3
Z2-Z1=0.3400 Z3-Z2=0.1700 Z3-Z1=0.1700
G34 Iteration: 4
Z2-Z1=0.0000 Z3-Z2=0.0100 Z3-Z1=0.0100
Target accuracy achieved.
Did 4 of 8
Accuracy: 0.01
Here is after G29…
It showed nothing in terminal other than probing failed. I made sure the wires weren’t blocking anything. It did the same thing went to probe the last spot and never clicked. then it dropped the bed…SLAM. Scared the 
out of me lol.
Interesting, why wouldn’t mesh leveling work on a flat bed.
in config.h did you edit your Z distance as well as your XY bed size?
oh…any idea what your nozzle offset is so far. Maybe you are a bit out of spec. It needs to be within -2.3 to -4.3mm.
Real BLTOUCH or a clone?
PS, this is really good.
It turns out, I won’t be help with Marlin either . Does it give you any reason why it fails?
Im 99.9% sure i did. It wouldn’t home until I did. It would move up 200mm and then error out.
Set at -3.8mm currently
Real
I havent put a straight edge on it but the bed looks as flat as can be. Thats why this probing deal is driving me crazy. Why can it hit every single spot but the very last one 
No sir… If im printing it just says probing failed and then goes on to print. This time it gave a kill code message on the printer screen and crashed the bed down. Disconnected from Octoprint. Had to reset the board to get it to connect back.
You should be able to print with without g29 if you want/need to use your printer. I will do some googling to see why that might happen. That last post was all my ideas. Just make sure you set the Z to your actual usable. Maybe it is 1-2 mm off and that is erroring out.
Ok i will double check that. I cant remember if i put it at 400 or the actual 380ish i can use. I will have to measure from the plate all the way down to the nozzle and get a true accurate measurement of what it is. I set up my slicer with 380mm but i believe it actually closer to 385ish
Oh there is a debuggig code, try this, “M111 S32 command before running a G29”
Yeah since we are homing at MAX it matters, normally it doesn’t. That threw me off at first as well.
Ok trying right now…
Put M111 S32 hit enter then G29 Correct??
Also do i need to run a G34 before hand?
ok from bed all the way down to the bottom of the fan shroud is 391mm, is that close enough or do i need to measure to the actual nozzle???
Ok just checked. I had Z Max position set at 380 in the firmware. Still dont understand why it can probe all the rest of the spots but the very last one with that. Changing it to 391 and hope thats close enough. Also going to change it back to probe 5 x 5 instead of 4 x 4
It has a margin of error of 10mm for one of the probes so I suggest getting it to within at least 5 mm. Just drive it up from the bottom and read the position. Sounds like you actually might be 1-2mm just out of spec.
About to load in the updated firmware and i will see what happens. Thanks!!!
G34 after change of firmware…
G34 Iteration: 1
Z2-Z1=3.9100 Z3-Z2=1.2100 Z3-Z1=2.7000
G34 Iteration: 2
Z2-Z1=0.5600 Z3-Z2=0.2000 Z3-Z1=0.3600
G34 Iteration: 3
Z2-Z1=0.3400 Z3-Z2=0.1400 Z3-Z1=0.2000
G34 Iteration: 4
Z2-Z1=0.0100 Z3-Z2=0.0200 Z3-Z1=0.0300
Target accuracy achieved.
Did 4 of 8
Accuracy: 0.03
Put in the M111 S32
G29…
And…bed crashed again
I don’t have an answer for you on this one, but I am just stepping into say you are not alone. My V4 does sometimes crash when going through the G29 mesh leveling process. I can’t say whether or not it is the last point or some random points throughout, but sometimes I will be sitting at my desk and just hear the bed come crashing down. It is rare though, maybe once out of 20 prints or so. But it happens and I am not sure why.
Im following along here…
The bed crashes?
Odd that the debug did not do anything. Did it probe at all?
