ripper2020

Okay, Here is my first video.  Sorry about the crappy footage, all I have is my phone to record. https://youtu.be/eKbsrQSNTxE
You can see that with my sel55210 I was finally able to get the tilt axis working so it stayed in position when I let go.  
The next video is trying to balance at all with the simga 19mm - https://youtu.be/wRE0M3pKWVQ. There is only one small spot in terms of moving the mounting plate forwards and backwards where the camera will sit anything close to level.  If I want it to point up to the ceiling, I have to move it all the way to the front and push the tilt axis adjustment all the way up.  However, then when I tilt the camera down, it swings back up.  Let me know if anyone has any tips.  I'm basically just trying to figure out if it will work with my setup or I'm just doing something wrong.
 

I did some very basic test footage of my son.  Strangely, to me, the unbalanced setup with the crane seemed more stable than the perfectly balanced setup (same exact setup) with the crane m.
Here is footage from the perfectly balanced setup on crane m: https://youtu.be/e6B3bsB8njQ
Here is the non balanced footage from full size crane: https://youtu.be/X1II_b7E7wY
When I say not balanced, basically the tilt and roll axis roll back to level shooting position instead of staying put.  I may just keep the full size crane and keep working to get it balanced...or just use unbalanced.  
 
 
 
 
 

Awesome, ordered it!  It's a lot cheaper than the other options I've been looking at too.  Thanks!

I have and really like this one: https://www.bhphotovideo.com/c/product/687341-REG/Oben_TT_100_TT_100_Table_Top_Tripod.html
I use it without the ball head, which is awesome as well, but it's sturdy, all metal, and fits right inside the zhiyun case no problem. 

It's actually pretty simple to figure out why it's not able to get balanced.
Since I suspect a CoG problem in the vertical direction, you can try shifting the base plate to the front a little bit, maybe to the front end in extreme case, then point the camera upwards, and hold the tilting motor housing in its place.
Now pay attention to where the camera falls:
If the lens goes forward (tip down), adjust the slider on the tilt motor backwards when camera is pointing up If the lens goes backward (tilt up),  adjust the slider  forwards If the slider is already at the very end, then your CoG is out of range. In this case:
If the lens goes forward, you need extra weight on top of your camera If the lens goes backward, you need extra weight at the bottom of your camera If you make it balanced, then put the camera horizontal, then balance it with sliding the base plate backward.
After that you can balance the roll motor, then pan motor.
The tricky thing is, that there are two degrees of freedom for the adjustments of the tilt motor, so pay attention to which one is off and which one you're actually adjusting.

If all you're after doing is adding to the weight of the camera then one option could be to get one of these hot shoe to tripod screw converters and then put some heavy washers on the screw part. 
The advantage of using the washers is that you can progressively add them to build up to the correct weight if thats what is causing the problem.
If it doesn't work then you'll only be a few quid out of pocket and at least you've got a hot shoe to tripod screw converter which are always useful to have !
And some washers for general plumbing emergencies.
https://www.amazon.co.uk/Camera-Mount-Tripod-Screw-Adapter-x/dp/B01KFUBALM/ref=sr_1_4?ie=UTF8&qid=1493939870&sr=8-4&keywords=hot+shoe+tripod+mount

If it helps, here are the photos.
The small ball head is actually needed to shift up the CoG a little bit, otherwise the Z (vertical) adjustment will be out of range and I won't get it balanced.
A good thing about the BMMCC is that it has three 1/4" holes at the bottom, I can use two of them to align the orientation.
You don't need to adjust the settings for balancing. When it's power off, it's not doing anything, balancing is pure mechanical. If the camera can stay at any position, you're ready to turn on the crane.