Tap Heat Dissipation - Just melted through hot end carrier

[Todd]

So, I just finished building and installing Tap on my 2.4 build. Running a Phaetus Dragon HF hotend and no mods except for the Tap. Z-offset calibration was good (~.1mm) and a small test print came out great. Then I started a print with a calculated runtime of 11 hours. All went well for the first 20-minutes, but then I noticed my first layer seemed to be getting thinner and finally disappeared altogether. I immediately halted the print and raised the gantry and found the four screws securing the Dragon to the carrier had melted through the carrier and the hotend was literally dropping downward. I was printing PLA at the time and hotend temperature was stable at 210 degrees C. I believe the root cause may have been my hotend fan beginning to fail so I am replacing that.

My question here is simple, has anyone else had issues with inadequate airflow through Tap and if so was it resolved successfully?

[Demosth]

Bummer!

@Todd Did you happen to take photos of that that you can share?

 

[Todd]

Photo 1...

[Todd]

Photo 2...

[Todd]

Photo 3...

[Todd]

Photo 4...

[Todd]

Final photo...

[Todd]

Both carrier screws were in tight even though a couple photos show one partially out. I had started to disassemble before taking the photos.

[Todd]

Back up and running with newly printed parts and a new hot end cooling fan. Found one listed as moving 8.29 cfm and 29.8 dBA. This fan moves significantly more air than the previous one. I'm sticking with my initial root cause analysis of a bad fan. Ran the old one on a test bench and observed huge speed fluctuations. 

So far, so good. Have a PETG print running now that's been running for 4 hours already and zero issues.

[claudermilk]

I somehow missed the photos on this (or was distracted and forgot). That's not a fun failure. I agree with your assessment that it was likely a bad fan.

[M3DV3]

honestly im not a huge fan of the HF version
same thing happened with me...clogs all the time and also the melting but my fan was completly ok
if you want to print fast or avoid this problems I recommend you a CHT nozzle without HF !
that was a proper solution for me
 

[Penatr8tor]

That's very interesting... I ran a Dragon HF for a long time. Printed a lot of ASA at 240-250 as well as other materials and only experienced a clog once. There are a lot of reasons why nozzles clog. My clogs happened primarily because I let printer sit idle with the nozzle at temp for an extended period without filament moving thru it. Of course filament quality can also cause clogs as well. A crappy fan or one that stopped working will definitely cause a clog.

[Todd]

The new hot end fan is a beast! Had to throttle it down in firmware to keep from overcooling. I’ll get some anemometer data in a couple days and post results based on varying airflows over the Dragon. The fan says it’s capable of >8 cfm, but I’ll reserve comment until I test it for myself.