Nozzle clog

Sovol SV08 MAX
1

Hi all,

I’m in dire need of all your help.

I work for Rinnai Australia and have recently got a SV08 max to print a very large print for a project.

I am using SUNLU PLA with a 0.8 nozzle. During the first layer I am constantly getting a clogging error and the print stops. I have tried different temps in the range of 200-225. I dropped the max flow rate from 21 to 16 and the problem happened later in the first layer but still happened none the less. I have lowered retraction speed and distance, and the clogging still occurred.

When the clog happened the first time I had to pull the entire thing apart and the filament seemed to be clogged in the small PTFE section, suggesting heat creep was the problem. The others clogs I was able to retract the filament, cut it and extrude it and I didn’t need to clean the nozzle out or do anything else it extruded fine ?

Any suggestions, has anyone else had these problems ??

2

Hi,
I’m not sure if that’s the problem, but if I were you, I’d clean the nozzle, even if you think it’s clean.
Heat it up to 300 °C and poke it with a needle a few times.

3

I don’t have a Max but do read everything on here. Any “advice” is second hand.

Question: Is your extruder actually clogging OR is the filament buffer (pusher) malfunctioning?

The buffer HAS been a problem for many owners. In order to function the reverse bowden tube MUST be free to move UP and DOWN to allow the 2 switches in the buffer to function.

How the telescoping switch functions.

  1. Buffer motor runs until the MAX switch triggers. Zero filament counter.
  2. Klipper keeps track of how much filliment is extruded.
  3. If too much (25mm?) filament is extruded before MIN switch triggers the “Clog Detected”
  4. MIN switch triggers [goto] 1

ANYTHING that prevents the telescoping switch from collapsing triggers the error. Most of the time there is NOT a clog but friction is keeping the telescoping switch from retracting.

Some users have reported good results from dismantling the buffer and shimming the spring in the telescoping output section (not the roller tension spring).

I have an untested mod in mind that may be simplier. Unload the filament, release the tube from the buffer outlet, thread a stack of washers (or nuts), weighing at minimum 10 g. over the tube. Reinsert the tube and install the wedge clip under the release ring. The added weight should assist the spring in pushing down on the telescoping switch housing.