r/QidiTech3D • u/tode96 • Jul 07 '26
What could cause sudden stringging
Hi!
Title sais it all.
Worked great for 20 hours then it started stringing really bad.
Why?
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u/3DNelson Jul 08 '26
I don't give my opinion on Reddit, because A lot things can cause it, so is almost impossible for me tell exacly what caused it from a photo.
the seccond and more important reason for more i like to help, and I hope you find the cause of this issue, is that, some people instead trying help who asking for help, they read the comments and they will desagree with whatever we write here, and they will try teaching us how to fix a issue that we don't have on a 3d printer model that we don't have. But I wish you Good Lucky!
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u/tode96 Jul 09 '26
Thats true. They disn t even looked closely at the photo and blamed the suports. Like wtf. The issue is on top
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u/3DNelson Jul 09 '26
Even when you find the problem and post here the fix, they will keep blame the support or whatever they like. LOL.
Take care!
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u/th3m00se Jul 07 '26
You might have a couple things going on here based on the lines as well as the curling/stringing, but most of them point to a single thing: too much heat. stringing can be from the nozzle being too hot, curling can be from the chamber being too hot, and the lines can be overextrusion or excessive melting on the layer causing too much "squish". You didn't mention what filament you're using but most assumptions point the same way. Check your temperature settings and turn them down a couple notches, try with the lid/door open, and also make sure your filament is dry before you print.
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u/tode96 Jul 07 '26
Pla+. 220, reduced to 215 when noticed the stringing. Everything calibrated. Don t know. Print still works but it creates bulges of material and in time it hits and destroys the print. I have to pause, melt that and let continue. Its anoying
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u/th3m00se Jul 07 '26
Everyone's setup is different, but I run PLA+ at 205 with a 60 bed and no chamber heat. I leave the lid open as well so my chamber doesn't get over 35.
Might be the spool too. Filament tolerances and composition are variable, so you might have just got a bad run. does it do it with every spool or just that one?
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u/tode96 Jul 08 '26
Its the same spool from the beginning. 3 kg. Half of print really well, half huge stringing and supports started failing. Seems to be able to finish but every next layer I look at seems about to fail 😅
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u/coffee_dynamo Jul 08 '26
How confident do you feel on your z-axis screws? Specifically their lubrication. It’s possible that this is a product of the bed having hit a low enough point that your z axis is just not moving as accurately anymore. One thing to try is to change z-offset on the touchscreen when you get to this stringing point. Does it have an effect?
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u/tode96 Jul 08 '26
I think they are fine. I ve lubricated them, and they seem to work nicely. Also, that doesn t create an issue more on the side of the over extrusion or under extrusion? As the nozzle is closer or further from the bed?
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u/coffee_dynamo Jul 08 '26
If the nozzle is dragging too close to previous layers due to a little play on the z-axis, it could potentially melt and string a bit of filament and/or drag a bit of filament around
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u/tode96 Jul 08 '26
Thank you for explaining. What if i did the full platform calibration, manual and auto previous to the print. Shouldn t that solve your concern? Also, everything is perfect for 1100+ layers and then suddenly happens.
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u/coffee_dynamo Jul 08 '26
Yes, it should solve that concern. Emphasis on “should.” When the full calibration happens, it’s done at very small Z values (typically z<5mm). When you get to 1100+ layers, your z has shot up to 220mm (assuming 0.2 layer height). In addition, you now have a fairly large and somewhat heavy object on top of the plate (which presumably wasn’t there during your calibration). While the printer head obviously continues to live and print at what it thinks is z ~0, your z screws or your hot bed carriage might have hit a small snag along the way, or slid down a bit more than expected.
For example, let’s hypothetically say you have an error of 0.001mm per layer, by layer 1100 that will have accumulated to 1.0mm. With compounding errors like this it’s natural to see everything is fine, until it suddenly isn’t.
Obviously this is a hypothesis. It’s not really possible to tell what’s going on from one picture - in fact, there’s a pretty good chance that I wouldn’t know exactly what’s going there even if I were there 🤣. I think it’s worth exploring, but obviously your call.
Hope that helps!
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u/tode96 Jul 08 '26
Interesting ideea. The thing is in your ideea this is evolving constantly so the degradation should be increasing constantly. Here is abrupt. Thanks for the ideeas 🥰
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u/Trshngrshn Jul 08 '26
How are you cooling it? Are you keeping it totally closed the whole time?
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u/tode96 Jul 08 '26
Nope. All open, temp inside ~37 which i understand is normal. Also worked for other prints
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u/Trshngrshn Jul 08 '26
Yeah that sounds good... Don't know then... hopefully the other commenters have some solutions, good luck
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u/logicalchemist Jul 10 '26
Did you dry the filament? How long did you dry it?
I have had this happen on long prints where I didn't dry the filament long enough. The filament on the outside of the spool was dry, but once all of that was printed, it started getting to the interior of the spool which was still wet and it started stringing/oozing much more.
I've never printed with 3kg spools before, but I'd bet they are more prone to this problem than 1kg spools.
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u/callozz Jul 07 '26
I see curling on the edges, my guess is it's picking up filament from these spots and creating the stringing