[Chiuso] E3D V6 Hotend - Fix for unscrewing stuck heatbreak from heatsink  

E3D V6 Hotend - Fix for unscrewing stuck heatbreak from heatsink

I'm a relative noob and ran into my first episode of having to disassemble the entire hotend to see if I could fix a clog that appeared to be further up than the usual nozzle/heatbreak problem. I'll spare the details of that adventure (it was fun!), but I wanted to post my experience with trying to disassemble and separate the E3D V6 heatbreak from the heatsink as the ultimate solution that solved my woes is not something I found in my internet hunting.

While disassembling, I followed what appears to be the standard advice and removed my nozzle (at high temperature) from the heater block first, before anything else, and then removed the heatsink. When I unscrewed the heatsink, the threaded heatbreak came with it and, once free from the heaterblock, the two of them were now inseparable newlyweds. Nothing I could think to do would let me unscrew them from eachother. The heatsink and the heatbreak were "glued" together and cleaning the clogged insides now seemed impossibly complicated (one major issue is that the heatsink is both delicate and threaded which makes it tricky to grab onto and fasten with much force).

I searched online and found lots of advice but, none of the creative solutions presented, actually worked for me. Skipping passed several missadventures (including the moment when I accidentally melted the black boden collet that holds the PTFE tubing in place with a heat gun, gluing it to the heatsink as well as causing some if it to ooze down inside), I ultimately bought a new V6 hotend (on the bright side, I had been thinking of getting myself a backup anyway) and then, because I'm special, spared no time in recreating the exact same situation with the new heatsink and heatbreak!!! Fortunately, I accidentally ran into a solution that, ultimately, allowed me to separate both pairs of heatsinks and heatbreaks. If you find yourself with this problem, here is what worked for me.

First, I should mention: if you are planning on disassembling the entire hotend, might I recommend that you ignore the standard procedure and first, at room temperature, unscrew the heatsink and then the heatbreak from the heaterblock (before removing the nozzle!). I believe that, in most cases, this should allow you to retrieve the two items separately, rather than stuck together. (If anyone knows of a good reason not to do this, please chime in). If, on the other hand, like me, you have already got yourself a stuck heatbreak/heatsink assembly, here is how I safely got the two of them apart:

1. If you haven't already, remove the nozzle from your heater block (this, of course, requires heating the block - you can do this on the Prusa, even if you have already removed the heat break and heatsink - of course, always use common sense while dealing with the super hot and now exposed heater block and nozzle).

2. Turn your printer off (unplug it to be safe) and let all your components cool to room temperature.

3. Manually screw your nozzle into it's threaded hole in the heater block.  Screw it all the way in, as far as it will go, and then loosen it back a 1/4 turn (as described in step 3 of the E3D V6 Hotend assembly instructions here: https://e3d-online.dozuki.com/Guide/V6+Assembly/6 )

4 Now (we're essentially still following the assembly instructions) take your stuck Heatsink and Heatbreak assembly and carefully screw the whole thing into the opposite side of the heaterblock (following the instructions, just as if you were simply screwing in the heatbreak while assembling it). Screw the Heatbreak/Heatsink all the way in - so that it buts up tightly with the nozzle (again, almost exactly what you would do if you were assembling).

5. Next, with the help of a wrench, tighten the nozzle a little bit more, back into the heaterblock (as tightly as you can comfortably handle, without feeling like you are forcing anything).

6. Finally, now that you have something that can effectively hold the problematic threaded heatbreak fast (in this case the heaterblock and the opposing nozzle), gently unscrew the heatsink from the heatbreak.  If all goes well, your heatsink should finally come free!

7.  Unscrew your nozzle from the heaterblock and you will now be able to retrieve the heatbreak as well. 

I've repeated this process a couple of times now with success.  In each case, I don't think that it was necessarily melted plastic that married the heatbreak and heatsink together (you'll find in your google searching, that this is often the suggested culprit of the stuck assembly). Instead, I think it was simply sufficient heat/expansion/retraction that did it.  If, while disassembling your hotend, you follow (what I found to be) the standard instructions out there and remove the nozzle before removing the heatsink, your heatbreak will no longer have anything holding it tightly in the heaterblock and so it will likely come out as you unscrew the heatsink (especially if you do this at high temperature). They will now, of course, be thermally tightened together. If that's not your goal, you'll have a bastard of a time trying to get them apart by other means.

Anyway, hope that helps anyone who runs into the same problem.

Again, I'm new at all of this and so if anybody sees a potential problem with this advice, please jump in.