Anybody an idea what could be going on here? My prints were perfect, and suddenly this happens (see picture). I re-calibrated once more, after I cleaned the nozzle as much as I could. But seems not to help. I have the feeling that sometimes there is no flow of PLA, because the Skirt should have 2 lines, but on the right and top/bottom only shows 1 line. See picture.
Is there a glob around your nozzle? Or is it just covered with random bits? If so, they need to be removed while the nozzle is hot. If you have a soft brass or copper bristle brush, you can use it to remove the gunk as well.
If that is all good, try running some first layer tests, like the 5 square test, and see how that works out. Some of these strands are very stringy, so itās difficult to know what is actually going on w/o seeing a video. BTW, about how many hours do you have on the nozzle? Have you printed with any abrasive filaments (i.e. glow in the dark, polycarbonates, glittered filaments, etc.)? What does the nozzle hole look like close-up?
In a previous attempt, there was a kind of āglobā around the nozzle. Looks like all the PLA was āstringingā together at it (not a āfull globā, but kind of wires mixed together). I have cleaned it as good I could, being careful not to damage the nozzle of course.
Where can I find this ā5 square testā? Did a google search, but couldnāt find anything useful.
Iām almost sure it has to do with the first layers, because Iām now printing again a small part that I printed before, and the first layer seems not as nice as before. The rest of the print looks perfect. When it is finished I will put a picture in the forum.
What I did see, looking closely when the Skirt was printed, is that there was no PLA visible in the beginning.
From the picture, the Z Offset appears to good. Are you saying that it takes a couple seconds, or around 50-80mm, when starting the skirt before you see any filament? If so, that is normal. If youāre saying that there is filament being extruded, but it is not sticking, then you might need to lower the Z Offset a bit, by like 0.1mm, or more.
Here is a link to the First Layer test on Teaching Tech:
Thanks, I will try that link.
Forgot to answer you on how long Iām using the nozzle. Hard to tell, but itās still the original one. It must be in use for a few 100 hours I guess.
Additional Question: How can I lower the Z Offset with 0.1mm. Do I need to do another calibration, or can I just tweak it with 0.1 mm?
Take a close look at the hole in the center. If the edges look worn, or if the hole looks larger than a new nozzle (compare to the spare that came with your Snapmaker), then youāll probably need to replace the nozzle. The life of the nozzle will vary, depending upon the temperatures used, number of hours printing, and types of filaments used. You can get like 10-20 brass MK8 (the size) nozzles from Amazon for around $20-30. If you need to replace either the nozzle, or the entire hot-end assembly, there are tutorials available from Snapmaker.
I would indeed assume that the number of hours will depend on the quality of the nozzle. Any idea on what the ānormalā life time of the standard SM 2.0 nozzle is. Do we talk about 100 hours, 500 hours, 1000 hours?
By the way, below some pictures of the smaller part I just printed. Apart from a little ādefectā on the Skirt, it seems to look perfect to me (printed at high precision).
Just started the failing print again. I found how to do a Z-offset. I took it slowly, and gave it -0.05 mm. But I also used a Brim of 8mm this time. So far so good, everything looks perfect. Although, the Brim will allow to get a better view on the quality of the first layer, I suppose (no need for the 5-square test yet). I will send some pictures later.
@CNC-Maker - So far, thanks a lot for your support!!
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Sounds good, and it doesnāt look like youāre having a nozzle issue, unless itās getting clogged. Here are the answers to your other questions:
Nozzles are consumables, and there is very little difference between the ones out there, other than the precision of the machining. If the machining is poor, youāll have a lot of jams/clogs, as the filament will get stuck in the machine groves. The best that you can do is look for good ratings, and good reviews, filtering out the complainers.
As for the number of hours, I canāt really say. Some people need to replace them every couple hundred hours, while others can use a nozzle for a few thousand hours, and I donāt think that anyone has done a study specific to the Snapmaker. Iāve only replaced the nozzle once on my Snapmaker, and it was after a couple hundred hours. On another printer, Iāve been using the same nozzle for over 2,000 hours.
In these pictures, the skirt looks like the nozzle may be a little too close to the bed, which lead to that glob. The part itself, looks very good, but the strings are a little concerning. On the side of the top picture, are those strings? Or. are they scratches?. What PLA are you using, and what temperature are you using for the nozzle? On the Snapmaker, most normal PLAs print best around 205Ā°C.
BTW, the High Quality setting requires an almost perfectly tuned machine, in order to work well. If your machine is over or under extruding, the issues will be greatly magnified. Have you tuned your Snapmaker? You can use the Teaching Tech Printer Calibration to go through each of the steps. For the Snapmaker, only the following really apply:
- Extruder E-steps Calibration
- Level the bed (yours looks pretty level already)
- Flow rate should be at 100%, or calculated using Flow Rate % =
(2 - (<filament diameter> / 1.75)) * 100 - First Layer
- Baseline Print
- Linear Advance Tuning (takes a while, but really needed for High Quality)
- Retraction Tuning
Every different filament, including colors of a specific brand, may have different temperature characteristics, so you might need to perform a Temperature Tuning for each one, but Iād only do it for ones that youāre having issues with.
As promised, here some more pictures. I used a Brim this time, which (I assume) can give some visual on the quality of the first layer? Maybe I did wrong with using Z-offset of -0.05, and should try +0.05 next time. Bottom left looks really bad. The rest is still ok-ish?
What temperature are you printing at, and what brand of PLA are you using? In the pictures, it looks like the temperature is way too high. Itās at least 10Ā°C too high.
Iām using the standard Snapmaker PLA that was delivered with the device. Iām printing at 205Ā°C. I will try with 195Ā°C or 200Ā°C.
Leaving on holiday now for a week, so will do that after Iām back.
Try ordering some better filament.
If you are limited to amazon, i would say get hatchbox
if you want to order some GOOD filament, order from Matterhackers or Prusament. They are sold for good pricing on their respective web sites and are top quality.
There are other good brands around, but if you print with junk filament for awhile and then see the difference with GOOD filament, you will not want to go back lol.
I have the same issues. I changed the nozzle, re-calibrated and t is only getting worse.
Something similar happened to me. Apparently the problem was that the filament wasnāt sticking well to the heated bed, maybe because of some oily dirt. I solved it by washing the surface with common dishwashing detergent, to remove any greasy layer from it.
Dishwashing soap is fine, but itās recommended to also use rubbing/isopropyl alcohol after. Between the two they will get rid of anything that might prevent adhesion.
-S
Iāve been off for a while due to holidays. But now I have experimented with the calibration of my SM2. I used the āTeaching Tech 3D Printing Siteā (https://teachingtechyt.github.io/index.html).
I performed the E-Steps calibration, the First Layer and the Temperature.
-
For the E-Steps, I needed to do a small correction (I was off 20 mm).
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The First Layer was more of a drama. I autoleveled first with a bed at 75Ā°C (as it is cooling down during the calibration itself), and did a 4 x 4 grid calibration. After that I did several runs, tuning the Z-Offset to +0.1, -0.1, ā¦, but there were always squares (out of the 5) that were really bad.
The Bottom Left for example looked best:
But at the same run, the Center one looked terrible.
I never could get them all perfect. -
As been suggested in this thread, my temperature of 205Ā°C was probably 10Ā° too high, so I was curious to see the Temperature calibration. I ran it from 190Ā° up to 210Ā°C. To be honest, I couldnāt see much of a difference between the temperatures. The overhangs were bad at all of them, but the rest of the print looked quite smooth.
At the end, I have made a few prints for a project Iām working on. I used the center of my bed, and tuned the Z-offset to -0.15, which gave me perfect results (at least, in line with my expectations). The top of the 4 items was at the bottom during the print (I print them upside down). The small pieces (the largest one measures about 19mm x 19mm) stick perfectly to the bed, without any deformations.
Conclusion:
Lowering the temperature to 195Ā° and tweaking Z-Offset gives me the feeling that the print results improved. But I fear that for large pieces, which use more the boundaries of the bed, there might still be problems with the bottom layer.
Iāve had the same experience with the temperature tower, it rarely gives me clear results even though I can see the nozzle temp changing on the touchscreen. Ditto for Linear Advance.
What I do instead, these days, is cycle through a small print with corners and bridges, stopping the print as soon as it looks bad, and iteratively find the optimum temp and K-factor that way. Sometimes e-steps as well, itās a lot faster than re-doing the e-steps procedure for what is usually a small adjustment (assuming filament type hasnāt changed).
It sounds lik a huge waste of time, but I am able to dial in a filament in an hour or two instead of a day or two.
Just a short update.
I had purchased PLA+ filament from Sun, but waited to use it until my standard Snapmaker filament was completely used. I now used the PLA+ with a printing temperature of 210Ā°C (PLA+ uses higher temp), and the results are great so far. With my standard Snapmaker PLA at 195Ā°C I have seen improvement, but started to get warping at the end. With the PLA+, I have none of these issues. With other words, the suggestion of @MooseJuice āTry ordering some better filamentā seems to be the most obvious, but correct response here. Although, I read somewhere that Snapmaker rebrands SUN, which means that SUN is not that good neither. Although, the difference might be that Iām using PLA+ instead of PLA now.
I have also discovered that after calibration, I still need to use Z-offset of -0.1. If I leave it at 0, or even use -0.05, then the skirt is even not sticking perfectly. With -0.1, I get great results. With other words, donāt trust the calibration - do a test print and then tweak the Z-offset.
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@hbilliet I have no idea what filament Snapmaker rebrands, but with it being a rebranding it stands to reason that Snapmaker is sourced the cheaper quality of filament from whoever they source it through. This is typical for products that are just rebranded versions of bigger brands that are otherwise good quality products, it allows the cost to be cheaper due to lower standards, on top of being cheaper because they arenāt having to pay for the more reputable brand name being on the sticker of the spool as it wonāt hurt the reputation of the actual manufacturer of it if itās lower quality.
In short, if Snapmakerās filament is just rebranded SUN and is why itās so problematic, that doesnāt necessarily mean that the actual SUN branded filament is of the same lower quality, I hope that makes sense.
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