Well dam?
Wow good!!
I have the same problem and I canň solve it. I tried better cooling, other temperatures and nothing helped. I have anet a8
Looks like an issue with your z screw. Print a few cal cubes and see if it happens at the same point every time.
@Jonathon_Thrumble
Yes, it the same point every time 
Check all the screws and belts for bits of plastic / dirt in them
That smells like heat creep. As you print, heat slowly creeps up the hot end causing plastic to start melting sooner and sooner. Eventually the plastic is melting high enough up the hot end that it swells and starts jamming. Combination of lower hot end temperature and more cooling of the mid/upper part of the hot end should help.
It acts like the z stepper takes a skip? I oiled the lead screw and bearings, and adjusted my bed height a little. It moved the skip area up the print about an inch?
Looks to me like an extrusion issue, not a Z motion issue. The outer contours of the print look continuous but with gaps where there’s missing material and then tried to print onto a missing layer.
White filament is often worse-behaved than other colors, by the way. And heat creep can happen around a consistent point due to changes in extrusion flow rate and retraction requirements. (It’s most common where the print speed slows down, but other stuff can trigger it too.)
@Ryan_Carlyle no you can see the z skip, then it prints in the air for a few?
Here’s what I see in the photo. Maybe you can see better/different in person.
missing/deleted image from Google+
Z axis issues like binding will cause under-travel, not skipping/over-travel.
It’s rare for 3d printers to travel FARTHER than they’re supposed to in Z… although it is possible. Specifically, if your printer turns off the Z stepper between Z moves, and then the bed drops under its own weight, you can get excess Z travel. But that happens where friction is low. And I don’t know if your printer turns off the Z stepper. Most printers never, ever disable steppers mid-print.
Your picture doesn’t show the z-axis couplers. This can happen with spring-type couplers if you have any binding. The couplers are compressed until the z-axis reaches a point that is not as bound up, and the spring pressure is released giving you up to a millimeter of z-axis jump.
@Ryan_Carlyle thank you, I’m doing some more testing tonight, I got this printer used, with some questionable mods done to it, it’s a xyz, it’s had bearing support done and hot end fuse added, I had to completely rebuild the hot end and undo some mods, then I added a Bowden tube set up. The z coupler is a piece of shrink tube? I think that might be a good place to start?
@James_Whittington the coupler is a heavy piece of shrink tube? I got it used, still some work to do?
