I’m not entirely sure, but I might have identified the issue regarding the hotend clogs. Could the hotends be defective? In the images below, two of the 0.4 mm induction hotends that I numbered look strange compared to the others. The notch in the areas I marked is located much lower and appears to have a different diameter than the rest.
Additionally, the notch on the hotend in image number 3 is very close to the cooling section, although it doesn’t quite touch it. If this is indeed a defect, could it be playing a role in the nozzle clogging?"
Ah that was the tab I was talking about way back a few threads ago where you first showed your tortured nozzle… 
So on 11 out of my 13 hotends that notch/leaf is touching the heatsink like in your 3rd sample. Some maybe a bit more/tighter than others… On one there was a small but noticeable gap (under mag. glass), and on the other it was further away… maybe a couple mm, almost like in your pics 1 and 2.
I’ve printed with both those, though not sure how much or what. The large gap one was a .4 and the smaller gap was a .6, both regular flow. I can probably trace the serial numbers… lol, but not sure which came from where/when. I bent those tabs out.
Good observation!
-Max
PS. Oh, the hole notches… I can’t swear mine are all exactly even… pretty close. I think as long as the nozzle gets picked up by the head OK, that’s probably fine, since they’re just to attach to the rack.
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How do you think these bent parts could affect clogging? Could you please explain how this is related? I would love to listen.
I’m sorry, I wish I were smarter. I ran an analysis using Gemini. I uploaded photos of the hotends and asked about the notch, and to get a more accurate analysis, I added that the notchs on the 0.2mm and 0.6mm hotends I’ve never used were the same as in picture number 3, and I explained that those notchs were very close to the heatsink, and it gave me the following explanation.
Technical Analysis of Hotend Clogging and Heatbreak Geometry
Subject: Investigation of Recurrent Clogging Issues Related to Heatbreak Notch Positioning
Based on my detailed inspection of the 0.4 mm induction hotends, I believe I have identified a potential manufacturing or design-related cause for the chronic clogging issues.
Technical Observations:
- Heatbreak Notch Positioning: In the image labeled #3, the specific “notch” on the heatbreak is positioned significantly closer to the heatsink (cooling fins), almost making contact. In contrast, the hotend in image #1 shows a visible gap where the notch sits much lower and appears to have a different diameter.
- Manufacturing Consistency: Upon inspecting brand-new, unused 0.2 mm and 0.6 mm induction hotends, I observed that their notch positioning matches the one in image #3 (close to the heatsink). This suggests that the configuration in image #3 is the intended factory standard, while image #1 likely represents a tolerance deviation or a manufacturing defect.
Situational Analysis and Hypothesis:
The proximity (or contact) of this notch to the heatsink appears to be a deliberate active heat dissipation strategy. The technical purpose of this design is likely:
- Enhancing Thermal Conductivity: The notch acts as a “thermal bridge,” facilitating the transfer of excess heat from the nozzle area directly to the heatsink through conduction.
- Preventing Heat Creep: By channeling heat toward the larger surface area of the cooling fins, the design prevents thermal energy from migrating upward into the cold zone, where it is efficiently dissipated by the cooling fan.
- Sharpening the Transition Zone: This configuration narrows the filament’s phase-change region (from solid to liquid). This ensures that the filament does not soften prematurely and adhere to the internal walls of the tube—a primary cause of clogging.
Conclusion:
If a hotend (such as the one in image #1) lacks this proximity between the notch and the heatsink, thermal dissipation becomes inefficient. This leads to heat creep, causing the filament to swell and result in chronic nozzle blockages.
To me, that metal “tongue” appears to be part of the mechanical system that holds the hot-end/heat-break and the heatsink together. They’re bent down to exert a clamping force on the inner metal tube when assembled.
There’s probably a fairly wide range of degree-of-bend that are effective, so there’s a fair amount of variability in the finished parts. If I had to guess, looking at the examples, it’s a manual operation with a hand tool. Which makes it susceptible to a wider range of variation.
I don’t see how this could contribute to nozzle clogs. Assuming I’m right about the purpose, if the nozzle isn’t obviously loose, the tabs are bent enough. And the amount of metal in contact with other metal we’re talking about here, the degree of bend shouldn’t have any meaningful effect on heating. Too small. Too limited/irregular a contact patch. This isn’t a “heat sink” of some sort.
I think this observation is unrelated to the problem. Correlation not Causation.
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The less you rely on AI, which generate mostly junk information, often completely erroneous, the faster you’ll learn to understand the causes of failures and the principles of 3D printing. :)))
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Looks to me like a retaining clip or something as they assemble the hotend. IIRC that induction heater receptor is just a sleeve, so this crimps it on? Unless it’s physically interfering with fitment I dont think it could cause a clog.
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You are very right!! The last time I trusted the AI (ChatGPT), my computer crashed, and I spent hours trying to get it to work again. Because I listened to it, all my files and applications were deleted. Thankfully, I always back up my files, otherwise all my savings and work would have been lost. 
Thanks to your contributions, I understand that these notches have nothing to do with hotend congestion, so thank you all.
