Filament splattering?
Hi all,
I've got a few hundred hours on my MK3 without many issues, but now a new problem has developed. When printing with any filament, and any type of model, big blobs of melted filament randomly spray out over the print. I can't pinpoint any specific changes that could have led to this. Slicer settings are fairly consistent. I did recently change the nozzle, but the issue was happening both before the change and after. Any ideas what could cause this?
This particular print was with PLA to show an example:
Would appreciate any suggestions about what could suddenly cause this. Thank you!
RE: Filament splattering?
It looks like an improper reassembly after changing nozzles. If the nozzle doesn't meet the heat break and the two aren't torqued together properly, a leak will occur. You can check for this by inspecting the heater block - any melt coming down from the top is a sure sign, Also, the nozzle set too deep into the heater block is another clue it's an assembly issue.
RE: Filament splattering?
Could be also fillament issue, uneven fillament extrusion due to some dirt inside or increased fillament humidity?
Do you encounter it on all prints and all fillaments?
What is the fillament brand? Did you use it before with success?
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RE: Filament splattering?
"Sprays out" sounds like a filament moisture issue. Try a new roll of filament? And make sure you keep your filament dry.
RE: Filament splattering?
If the nozzle doesn't meet the heat break and the two aren't torqued together properly, a leak will occur. You can check for this by inspecting the heater block - any melt coming down from the top is a sure sign
That was it! Upon closer inspection, there was a bit of melt coming out between the nozzle and the heat break. Torqued it down a bit more and it seemed to have fixed the problem. Thanks!
RE: Filament splattering?
Make sure the nozzle lip does not touch the heat block. After torquing, there should be a little gap if you did it right.
RE: Filament splattering?
At first, I did leave a small gap (like the width of a sheet of paper) but that seems to be what led to the leakage / splattering so I torqued it down further to close the gap.
RE: Filament splattering?
Follow the E6 installation instructions... The E6 web site has detailed instructions.
The heat sink screws into the heat block.
The nozzle screws in until it contacts the heat sink. That is what you torque against.
If you don't have clearance left - you need to screw the heat sink into the heat block more. Maybe half a turn.
The nozzle must be tight against the heat sink - or it will leak.
RE: Filament splattering?
At first, I did leave a small gap (like the width of a sheet of paper) but that seems to be what led to the leakage / splattering so I torqued it down further to close the gap.
Just to be clear: The hex of the nozzle should NOT touch the heater block, and should protrude roughly 1mm to ensure that the nozzle is being tightened against the heatbreak to ensure a tight seal. Based on recent experiences, I'm leaving roughly a 1mm gap between nozzle hex and heater block before the heated final tightening at 285C. After tightening, I've got an easily visible gap between the nozzle and block when everything is tightened. This has been working very well against multiple nozzle types and manufacturers for several months.
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RE: Filament splattering?
Do what Bobstro said. As usual. And wherever I said Heat sink - it is the Heat break.
RE: Filament splattering?
Do what Bobstro said. As usual. And wherever I said Heat sink - it is the Heat break.
This is why the inability to edit our own posts drives me nuts. I'll often make a simple mistake but have no way of avoiding confusion unless the reader keeps scrolling.
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He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan
RE: Filament splattering?
Piling on - here's an image of a hot end with the appropriate gap between the nozzle hex and heater block. Understand though the nozzle is firmly abutting the heat break inside the heater block.
RE: Filament splattering?
Interesting... I appreciate the further clarification, and it definitely makes sense. Nevertheless, when the hex of my nozzle has a gap with the heat block, I get filament leakage, but when I tightened it down, so it abuts the block, my prints have been perfect. Maybe my heat break got moved higher up somehow, so I now need to overcompensate by screwing the nozzle in farther. I can't find a good away to adjust the depth of the heat break, and it doesn't really seem to be causing any issues so I suppose I'll just leave it alone for now! Thank you for all the info!
RE: Filament splattering?
[...] when the hex of my nozzle has a gap with the heat block, I get filament leakage, but when I tightened it down, so it abuts the block, my prints have been perfect. Maybe my heat break got moved higher up somehow, so I now need to overcompensate by screwing the nozzle in farther.
Inspect the gap between the heater block and heat sink. If you're not seeing any filaent leaking there, there's no need to panic. However, I can tell you from experience that you do want to deal with this when things are calm and you have good light.
I had very much the same experience. After replacing several heatbreak components, I inserted an E3D nozzle per the instructions, left the small gap and hand tightened the heatbreak to the nozzle. Heated to 285C and did a final tightening of the nozzle. There was a small gap between the nozzle hex and heatbreak and all was well. Until I swapped nozzles and found some wound up tight against the heater block.
I print with a variety of nozzle sizes and brands, so if you stick exclusively to E3D, this might be less of an issue. However, the lesson I took from this is that you're better off having the initial gap beween nozzle hex and heater block -- before tightening at 285C -- be a bit more than 1mm than less. This gives a bit of wiggle room for nozzle variations, and the gap is still good once tightened. Worry less about a precise measurement and focus on ensuring there's a good seal between the nozzle and heatbreak.
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He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan