Well, I got the replacement hot end in today. Here is, to the best of my recollection how it all went as far as replacing it. My nature is, dive in and learn, so I have no idea if there is another (more than likely better written, as well) guide out there. If there is, you might check it out.
Standard disclaimer - Don't blame me if something breaks, this worked for me but that doesn't mean it will work for you.
In the box they sent a nozzle, a replacement barrel (brass tube with threading on the outside), a replacement heating element, and a small length of kapton tape (thank you so freaking much for thinking of the little things, Solidoodle!).
First, remove the two sleeves that surround the nozzle and heating element, they slide right off with minimal force.
In removing the extruder, I removed the four screws that attach the stepper motor and the rest of the assembly behind it (heat sink, fan). Laying it gently to the side, I then removed the two outward facing nuts that attached the clear acrylic assembly to the printed bracket.
Unclipping the clips was a bit of a pain, but a small pair of needle nose pliers and a light tug on the top of the clip and they popped right out. At this point I removed the thermistor using an exacto knife to make a small cut in the kapton surrounding the nozzle. Once both were removed, the assembly is free and clear of the machine and can be worked with more closely.
There may be a way to change this out without having to completely disassemble the acrylic structure, but I have no freaking clue how that would work. Considering the actual problem is the heating element is dead, there is going to be a mess of solidified abs that really doesn't want to spin.
So, I disassembled the acrylic assembly, removing the bearing arm as one piece and then removing the one other bolt/nut that clasp all of them together. Note to anyone trying this, there are two small inserts that are clear acrylic and if you happen to be an idiot like me, can get lost in a hurry.
At this point you have the PEEK tube with some left over ABS poking out the top, and everything beneath it.
Now, I did try to just remove the nozzle and hot end while it was still in the machine, however knowing the delicate nature of this I didn't put a whole lot of effort into that because I knew I could end up breaking something. Once it was out, even with a body builder friend grasping onto the PEEK tube and a wrench, I could not get the nozzle off. In hindsight, it might be easier to break the nozzle from the heating element first, as they were actually under some tension. I did not take this route, however.
Around the PEEK tube I fastened a hose clamp, so that it would hopefully not damage the tube at all. Once it was in, I placed it inside of a bench clamp that I VERY LIGHTLY tightened down, so that the force would be applied as torque to the body of the tube and not actual clamping force. It took a heck of a lot of force to get it off (twisting the ABS, plus whatever torque is placed from the factory.
The nozzle came off first, then I removed the heating element. At this point, there was no reason I could think to replace the barrel, as it was not damaged in the removal of the nozzle and heating element, so I left it, replaced the heating element (smooth side towards the nozzle, not the slotted side, this is how it was assembled). Once the two parts were replaced. I began assembling the acrylic structure (this can be tricky, I'll try to get a better guide on how to fit it back together later). DO NOTE - ONE SCREW IS LONGER THAN THE OTHERS. This actually matters, the longer screw that is not entirely threaded is the one that is used on the bearing arm for tension adjustment. I kind of forgot that and it's a massive pain in the butt removing and replacing everything again. So don't do that.
Once finally put back together, I fired it up in Pronterface to the time tested, mother approved 200 degrees. I began soiling myself when I saw either the PEEK melting, or condensation rising, a quick swipe with a cloth proved that it was merely condensation building up, or oil from my hands baking off, or something from the heating element. I have no idea what it was exactly, but I assume that is to be expected. It is printing like a champ now for about 2 hours.
As far as the failure, the adhesive/bonding agent that wraps the heating element appears to have begun cracking at some point near the entrance point of the wire. When finally removed I was poking and proding the thing and one of the leads practically fell out of the adhesive. One side of the circuit was still connected (soldered on), the other had desoldered. Personally, I think a crimped connection would prevent this in the future, when I go to make one in the near future, I will try it and report my findings back, I realize this will be hard though, due to the nature of the connection and requirement for an insulated wire. I've got the length gauge figured out, but out of respect for them, won't post it unless they have no issues with it.
Hope this helps.
