At the end of January 2019 I purchased an I3 Mega-s from Anycubic. About 2 weeks ago I finally felt I had got it dialed in where I was comfortable with it not printing poorly. Then it made this strange sound, like a grinding or clicking and the hotend would not heat. This machine comes with an extra hotend. I installed that and have had nothing but quality problems since.
I reached out to the manufacture with a list of issues and picutres. In my mind there were at least 3 issues.

  1. My prints were messed up along the z-axis.
  2. My 2nd hotend seemed too hot no matter what I temp I printed at. And the cooling fans seemed to either not be cooling or are cooling too much.
  3. When powered on, the machine makes a grinding noise for about 30 seconds to a minute while the system boots and warms up. ]

To fix #1 they sent me 2 new brass nuts that attach the threaded rods to the carriage and 2 new connectors that connect the threaded rod to the motor. These were installed. It seemed to help some on a piece I was trying to print. This piece is a a group of 6 tubes placed in a circle about 15mm in diameter. Each tube is about 4mm in diameter. Before I replaced anything this was a fuzzy mess. Afterward it was better but I gaps or chunks taken out of the sides of the tubes. And the top is still a fuzzy mess.

When I installed the new brass nuts I realized that no matter how tight I made the screws, one of the threaded rods has quite a bit of play within the brass nut. To the point where if I wiggle the top of the rod back and froth there is a clicking sound of the metal threads within the nut. The other is tight and I can get no movement out of the rod.
After the installation of the connectors and nuts, I ran a PID on the hotend and the bed, did a mesh level using Marlin firmware, and calibrated the extruder.

#2 and #3 are awaiting the delivery of a new power supply and cooling fans Before I can install and test.

Prior to this all going wrong, I was contemplating upgrading my hotend and extruder with a titan clone and my stepper motors in an effort to get better quality out of my prints. I had also started to look into small nozzles, (I have the standard 0.4) for improvement in detail.

At this point I have no idea which way to proceed.
Do I dare do the upgrades just in case I have a larger underlying problem or do I do them in the hopes that fix my problems? ’
Do I wait to install the new fans and power supply?
If they don’t fix my issue what is the next step?
Is the wobble in the threaded rod an issue or am I just being paranoid at this point?