I got an extra extruder kit for the ACE, both to have a set of spare parts (vs. buying them separately) and so I can have one ready with a usual 0.4 brass nozzle and another for a second nozzle type to quickly swap between. (I really like the easy extruder swap design on the ACE, very clever.)
While changing the nozzle on the new hotend, I noticed that some odd “goop” on the heatbreak where it threads into the heat block:
It’s probably nothing, but I’m curious: does anyone know what this is? Some kind of thermal paste, adhesive, or threadlocker? The hotend that came with the printer doesn’t have it, but the replacement one does. Something new they started adding?
As far as I can tell, it’s not filament residue. (There was some black filament in the nozzle that oozed out when I first heated it up—I guess Sovol tests the hotends before sending them out—but the nozzle threads were clean when I unscrewed it.) And nothing seems to be leaking in usage, so whatever it is, it seems like it was applied intentionally.
On the SV06, Sovol used blue threadlocker on the heatbreak..so it has happened in the past.
From that pic, it looks like thermal paste. Can you wipe off some paste, maybe with a toothpick..??
Have you tried to unscrew it..??
I was doing another nozzle change, so I took a closer look. I managed to pick a bit of it off, and I really have no clue what it is. It’s not like any thermal paste or adhesive that I’ve seen. Here’s a closer pic:
It’s hard and glassy, almost like a resin of some kind. It doesn’t seem like burnt filament (though I’ve never had a really bad case of burnt filament before, so IDK). And the nozzle threads were clean too, as was the inside of the heater block:
I didn’t think to try and unscrew the heatbreak, and the nozzle’s reseated without leaks, so I don’t really want to mess with it again. But I am curious, as this is a total mystery to me.
It certainly LOOKS like thread locker. I didn’t know till today that Locktite has products that work up to 350 °C. @sovol3d Be nice if they’d wipe off the excess before it cures.
If you need to unscrew it minimum strength seems to be at 150 °C and constant from there to 350 (for the red the blue actually gets stronger again above 150)
But I am curious, as this is a total mystery to me.