Sudden bridge failure
I've been experience issues with bridging ever since a massive blob built up on my extrude and detached the thermistor wires. I've since replaced the the thermistor with a new one, but print quality is noticeably lower, the problem is most apparent and problematic with bridging.
In the photos you can see the melting/clumping that's happening during the bridging process:
Here is the same part using the exact same settings printed before this issue appeared (the bridging is just about perfect), and the more recent print on the right:
Any ideas as to what's causing this? I've already disassembled, cleaned, and reassembled the extruder assembly, repeated calibration, and did a PID calibration. I also tried temperature calibration but that failed on step 2/6. Any other ideas?
RE: Sudden bridge failure
Please post photos on the forum. why? Links offsite can be fraught with problems, images come and go, and aren't there weeks later, and makes the forum less helpful in the long term..
RE: Sudden bridge failure
It seems I can no longer edit my original post but I'll attach the images here:
RE: Sudden bridge failure
Looks like Bridge Detection has been turned off or bridge print speed has been increased.
In any event, support should probably be used to improve the surface quality. It won't take much to make a major improvement: use a gap of 0.05 mm, spacing of 5 mm and no interface layers.
RE: Sudden bridge failure
@tim-m30
Though it doesn't look like it, the two print samples in the image are using the exact same settings, and I can confirm that Bridge Detection is on, and both have the same bridge print speed.
I've tried another test print using minimal supports and the results are slightly better, but I'm hoping to find the underlying cause of the dramatic drop in print quality. You can see in the attached image the difference in quality around the outer chamfered edge of the part. The edges of the part on the left are straight and consistent, while on the right they're warped and wavy.
These quality are especially problematic during bridging, but don't seem limited to that feature. Wondering what the underlying cause could be...
RE: Sudden bridge failure
If they use the same settings, then something happened that affected the extrusion ratio in the second smaller print; like a partial nozzle plug, etc.
The printer is rather consistent, and the two prints are different enough I honestly doubt the settings were the same. And it isn't just the bridge that is suspect.
Zip and post the two gcodes and the two project files (.3MF).
Or, if you zip and post the stl of the part, I can show you a trick to get inside surfaces to behave better, like this,
no supports, vs custom supports
RE: Sudden bridge failure
@tim-m30
"The printer is rather consistent, and the two prints are different enough I honestly doubt the settings were the same."
I can see why you would say this as the difference in print quality is so extreme, but the two parts pictured above are printed from the same file from the same SD card. It's the same gcode that I've printed successfully dozens of times.
I've been suspecting a hardware issue in the extruder assembly so I've already replaced the nozzle, ptfe tubes, and did a thorough cleaning of any excess filament residue in the extruder assembly. I'm thinking it must be a hardware issue related to a serious blob incident which seems to coincide with this issue. I just can't figure out what the culprit is.
RE: Sudden bridge failure
@tim-m30
I can see why you would say this as the difference in print quality is so extreme, but the two parts pictured above are printed from the same file from the same SD card. It's the same gcode that I've printed successfully dozens of times.
Well - that statement puts it further into the Twilight Zone. The two parts are radically different in size.
ps: Unless it's an optical delusion due to telephoto compression (first image).
ZIP and post the gcode ...
RE: Sudden bridge failure
And zip and post the Project or STL the part is created from.
RE: Sudden bridge failure
@tim-m30
I can see why you would say this as the difference in print quality is so extreme, but the two parts pictured above are printed from the same file from the same SD card. It's the same gcode that I've printed successfully dozens of times.
Well - that statement puts it further into the Twilight Zone. The two parts are radically different in size.
ps: Unless it's an optical delusion due to telephoto compression (first image).
ZIP and post the gcode ...
Ah, I just stopped the print early after seeing the failure 🙂
RE: Sudden bridge failure
@tim-m30
Thanks for your suggestions so far. The gcode used for the prints above is attached.
RE: Sudden bridge failure
That is an older gcode from Slic3r PE... can you zip and post the stl you are trying to print. I'd like to check for firmware differences that might be in play. Some new default in the firmware that now has a setting the old slice doesn't cover. I don't know of anything that should be there, but that's the only thing I can think of that might be happening.