Ender 5 Max filament constantly getting stuck in lower heat block

Ender Series Creality Ender-5
1

I am having issues with filament ruining my heat block. My printer is new (two weeks in use) and I am on my 4th lower heat block.

Today I printed a model that took about 1.5 hours using Creality PETG white filament. The unit was cooling down for about 5 minutes while I cleaned the heat bed, then tried to start my next print job. It was running for about a half hour when I noticed that there was still only the first layer put down. It was going through the motions but nothing was coming out. I thought the Nebula camera had AI that should have stopped this.

I had to fully disassemble so I could access the gears to remove the tiny bit of plastic stuck in there. I had to clear the white tube as well. I have not started to print again but this has been an ongoing issue.
This is now my 4th heat block, the previous 3 were completely ruined with plastic having blobbed all up into things.

I have also noticed what I believe is a major manufacturing issue. On the lower heat block there are the 4 wires that come off of it and terminate with two connectors. The larger of these wires have heat shrink on them. These are the wires attached to the ceramic tube for clarification. The problem I am finding is that the heat shrink is far too short leaving plain wire exposed and if the two wires are allowed to short together you get an error on the printer. On heat block #3 I used black electrical tape to keep them from shorting. On my most recent one I used a tube of silicone gasket to insulate them from each other and just gave it time to dry before using it. At $25 a pop I am starting to regret my purchase. Creality did provide me with 1 free one. But I feel I should be able to get much more than 72 hours out of these.

What do others do to prevent clogging in the heat block or the gears?
My most recent attempt at a fix was to issue some G-Script code at the end of the job to alter the cool down delays and retraction. I still had to take everything apart, but the block did not appear to be ruined this time. Has anyone else been seeing the issue with clogging or the bare wires and shorting?
The code I am testing for PETG end G-Code is as follows:
G91 ;Relative positioning
G1 E-2 F2700 ;Retract a bit
G1 E-2 Z0.2 F2400 ;Retract and raise Z

G1 Z5 ;Raise Z more
G90 ;Absolute positioning

G1 X395 Y395 F6000 ;Present print
M106 S0 ;Turn-off fan
M104 S0 ;Turn-off hotend

G4 S35 ;Wait 35s - PETG stays soft longer, needs more cooling
G91 ;Relative positioning
G1 E-18 F150 ;Shorter, slower retract - PETG is stringier and grabs more
G90 ;Absolute positioning

M140 S0 ;Turn-off bed
M84 X Y E ;Disable all steppers but Z

2

G-Code isn’t going to solve hardware issues… parts are not fitted correctly therefore you have problems…

3

Thanks for your reply. When you say parts are not fitted correctly what do you mean? Are you suggesting there is an issue with the placement of the lower heat block? Since that is only held on with two screws I don’t see how that can be misaligned.

4

… replacing the heatblock 3 times and still having the same problem… you still think you did a good job?

There is more than only fitting those 2 screws, what about the PTFE-tube that sits between nozzle and heatbreak? Did you check that? After some printing hours that PTFE-tube gets brittle and needs to be replaced… I bet you didn’t check that!

Besides that, the nozzle, PTFE-tube and tube coupler on top need to have a thight fit, so there are no gaps that let filemant “escape” when pushing through material. If that happens, you need to clear it, change out the PTFE-tube and reassemble everything…

5

Yes, I do still think I did a good job and honestly am offended at the implication. The PTFE tube gets replaced with each heat block as part of the replacement (so you bet wrong). The nozzle is also replaced as part of a new heat block and comes preinstalled.

I am working with Creality support, it appears there may be an issue with the gears or gear motor of my printer. I can initially successfully extract filament, but then doing printing you can hear the filament gears click while trying to advance the filament but none is moved forward. That seems to be causing whatever was in the extruder to over heat and clog the unit.

“you still think you did a good job” I was really appreciative of your response to my other thread about the Creality Print theme. This one, not so much as I infer a lot of accusation and sarcasm in this reply. I have watched the Creality videos several times for replacing both the heat block and the extraction/retraction process to ensure I am doing them right. I have also identified a manufacturing flaw for the heat blocks that I have reported back to Creality. Was it your intent to be insulting? If so please refrain from future responses. I may be new to 3D printing but I am not stupid, I am only inexperienced with this product and process. The Air Force made me go through NASA soldering school to be able to work on laser target designator systems on aircraft. Additionally I have 30 years experience in IT, so I really didn’t appreciate the tone of this reply.