Filament breaks after 1 hour.

So far its going smoother this run with black SD ABS, no temp variance outside of +/- 0.30 degrees. I'm beginning to suspect the sample filament is the culprit.

If you take off the front of the extruder, has the filament thickened just as it enters the tube leading to the hot end? If so, the cold end of your extruder is too warm.

The usual suspects...

One common cause is having the fan suck from, rather than blow into the extruder. If your fan is the same as mine, it looks right. But check, in case they switched fan vendors.

Another cause is the anemic air flow from the fan. Did you run without the plastic shroud on the front? It's not just a finger guard - it guides the meager air flow though those vertical slots on the front to pick up a little more heat. So run with it on. It ain't great, but every little bit helps.

Some people run with top or front of the printer open a bit on long prints to help cool the extruder some. This is a mixed bag, as your model is less likely to crack with the chamber shut up.

Don't run the hot end any hotter than needed for good layer adhesion. Otherwise it increases the cooling load.

Also, if you're not getting thumping without buckling, consider turning down your vRef a smidge to, say, 1.4 volts. Less current means less heat from the motor to dissipate. (But if your stepper starts skipping, you went too far. It's a tricky balance.)

If you've ever diassembled the heater block from the tube, make sure it's not touching the bottom of the extruder body, as that will leak heat into the cold end of the extruder. (If you haven't, don't mess with it unless you need to.)

I switched my fan around after the first print so it is blowing inward,

I removed this early on, I'm not sure if I still have it around, I'll have to check

I'm trying this with my next long print

Haven't yet figured out the golden temp for SD ABS, I've been running at 240 degrees. maybe too hot?

Are you talking about the extruder trimpot? its set at 1.5v

I've not yet disassembled the heat block

Also these are my current slicer speed settings for "medium" quality:

As I'm attempting to figure and sort out the issues, it seems others arise. I was able to get a successful print done, however it was smaller than the previous prints, so it may have not been solved initially. I moved onto a larger print when for some reason my computer was shut down via the power strip (either the dog or a child) in the middle of a print. It was looking like it might have been a good print but i had to reset everything and attempt again. however every print following afterwards with the exception of Z-Calibrations, it was printing like the bed was too close to the extruder causing the nozzle to scrape and drag the first print layers.

Here is the first print after the shut down:

So I rehomed everything cleared the glass with a bit of acetone and lay down some glue. Z-calibration and tried again. Same exact result. (Thinking I might have forgot to select which run was best) Performed another Z-calibration this is the result:

Another angle

Feel like I should stick with where its at 3.90 and run it again. If it still scrapes along, not sure what to do. Probably going to lower that extruder trimpot like suggested by trayracing and go from there.

I feel like the opposite was occurring, the filament was getting fed too fast and it wasn't hot enough. I've dialed in some slower settings in slicer and kept the top vented open and its been printing without major issues. For some of the earlier immediate failed prints I was flipping the models along the Z or Y axis within Soliprint to print without having to add supports (since I'm still fairly new to printing, and haven't figured out those settings yet). and the prints weren't "meant" to be printed on the side I put them on.

I'll report back in a bit. I'm currently on my 3rd successful print, I'll show my slicer settings when done.