Thanks! Yes I shifted the sock down, but also print first layer at a lower temperature to stop the oozing.
Ive had good results with cfpa too. This particular issue were discussing with regards to nozzle buildup & oozing is specific to cfpetg.
That explains why the prints have so much static. Our printers are generating lots of static electricity. Could that be why itās sticking to the nozzles as it dries?
Great! Iāll try it too! What is the first layer nozzle and bed temp?
200 for nozzle & 90 for bed.
I would try 230c nozzle and 70c bed. 90c bed I think itās too hot
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I have been having the same problem. Checked the sock and its torn. Pulled it off and there was filament all over the hot end.
On another note- For what its worth I have started using the engineering plate (green side) with the BL liquid glue. It is amazing. Everything sticks for hours, no warping, no weird edges. Cool down, bend plate and everything pops off like chocolate wafers. I have a special print I have been working on for months and its very long so i have to split and 1 out of every 3 attempts the part has warped with every other regular petg I tried. Lifted off the textured pei, with and without hairspray. Lifted off the high temp plate even with glue(though that worked pretty well for a few tries). Seriously guys, engineering plate and BLLG. The prints that did come out with the petg-cf were flawless on all edges and never lifted. Every edge at every angle on all 3 tries have been straight as an arrow and no shrinkage either.
Now hopefully the blobbing stops.
Iāll have to try that out, Iāve been having issues with PETG (not -CF though) as well. Honestly most filaments seem to stick around the nozzle. Iāve found that in general the wiperā¦ well it doesnāt. Iāve been using my Prusa defaults for PETG, so hopefully your temps produce some better results.
I dont have any issues with elephants foot at 90 & if I set first layer temp at 230 then the filament oozes out & onto the part.
I should add that im using the cht bimetal high flow nozzle.
Ah yeah high flow nozzle I didnāt know lol. Could it be a retraction issue then?
I did the retraction calibration & there was no stringing at any level of the towers so I ruled that out.
Ok so the sock helped a little but still has not resolved the issue. I left an overnight print and woke up to a fingertip sized blob on the bed, a pea sized amount stuck to the nozzle but all pieces finished, albeit with scarring everywhere. As others mentioned I did all the calibration from get. I used bambustudio for this run as orca has completely ruined me with that overhang debacle. I lost too large prints to that nonsense. I tried last night the 255/265 temps but didnāt help. If i do one part its not much of an issue as mentioned above. Any other suggestions? I need overhangs to come out properly as well and I even redesigned my part to avoid the overhangs but now this issue comes up.
This nozzle has seen alot of pla and petg action before- what is the best way to clean it and prevent the stickiness?
What infill are you using? I use rectilinear 15% and it helped me with my prints. Infills that have crossing or not enough support caused me issues before.
Hi everyone, not so long ago I opened a thread on this very same issue being discussed here, I accidentally missed this one when looking around the forum before posting on my ownā¦
Here is my experience, what Iāve tried and what I may try in the future. Keep in mind I still have this issue with Bambu PETG-CF and for me it completely makes this filament unusable as I canāt keep babysitting every print for hours and hours just for it to succeed. Iām also thinking about opening a support ticket to ask some questions directly from Bambu.
What pisses me off VERY much, is the type of this problem:
PETG can be a pain to print well and clearly has some downsides as any other 3D printing polymer.
What is amazing is how well carbon filling is contributing to the properties of PETG.
PETG oozes ā PETG-CF oozes less
PETG glasslike finish showing every little surface issue ā PETG-CF hides them being matte
PETG bridges poorly, poor overhangs ā better overhangs with PETG-CF
PETG sometimes too flexible ā PETG-CF stiffer
But, there is this downside that is the main culprit behind this problem as well: While you can print PETG with any brass nozzle, PETG-CF requires a hardened steel nozzle, as it is abrasive. Now PETG really likes to stick to steel nozzles, but now you have to use them. This is the core of the issue how I see it and Iāve yet to find a way around it. It is annoying that one of Bambuās main selling points of this material is a modification that makes it stick less to steel, however it is the exact same thing happening for me. In fact it sticks more than any other PETG Iāve used, so I call BS marketing!
After opening the thread and trying suggestions from the comments as well as trying suggestions from this thread, sadly, nothing has made a difference significant enough to resolve the issue. I havenāt given up on this as I REALLY want PETG-CF to print well for me, it would be my go-to filament whenever something doesnāt just have to sit on a shelf collecting dust, but rather some applied model that needs to have decent properties.
Here is my takeaway of things that might help as of now, I will update this whenever I find something new:
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Just dry your filament once again, if you canāt make sure
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Clean the nozzle, inside, outside. As suggested by @djeZo888 you can swap nozzle covers and make sure there is no residue under the lip of the silicone cover.
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Make sure the layers are perfectly flat: if a tiny bit is sticking out it will be contributing to the blob.
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For this, tune your pressure advance and flow rate, rather than just letting the LIDAR get an approximate value. Orca lets you do all this pretty quickly with little effort. Minimal underextrusion is in this case in my experience prefered over overextrusion. PA values way higher than expected has helped me and the flow was lower than expected as well. Flow can be tricky to tune when using the Orca flowrate test, with PETG-CF you want the lines just touching, ignore the seam and little bulges on the sides, just look at the middle of the rectangles, PA tuning will help with that later. Other print settings that are important are:
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Infill type: should be rectangular or gyroid or anything non overlapping, NOT grid
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reduce infill overlap: Bambuās 15% preset is imo way too high
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turn off ensure vertical wall thickness
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print inner/outer walls with same width
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reduce speeds and access, especially on outer walls
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try outer/inner and inner/outer wall order to see which works best. Inner/outer is preferred for me, as this material already has a sublime surface finish, and this way if there is an extrusion inconsistency, the material has more space to squish instead of bulging upwards.
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Arachne has helps a lot for me when printing thin features where inner walls donāt fit in perfectly
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Tune retraction and Z-hop. This was impossible for me with a retraction tower from Orca, as there was 0 stringing to begin with. You still want to find perfect settings so there wonāt be anything sticking out upwards from the layer after an extrusion path.
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Try plastic repellant paint on the nozzle. Slice has something exactly for this issue (Plastic Repellent Paintā¢ | PTFE Nanosuspension | Slice Engineering). My expectations might have been to high, this did help a little but but did not resolve the issue. It wears quickly and Iāve found that getting some dry high temperature PTFE based spray yields similar results with it being cheaper and widely available (make sure it is rated up to at least 270Ā°C).
The last and probably most important factor is the temperature. Iāve seen @cl33 mention trying different printing temperatures with no success, this was the case for me as well. However, Iām sure this issue would be reduced to almost no failed prints if I had the previous layer at the perfect temperature, when the next one is printed on it. This can be controlled purely by extrusion temperature, bed temperature, layer time, and mostly the fan speeds. I suspect this could single handedly solve this issue if set perfectly. Currently Iām playing around with this, Iāve seen @ant in a different post mentioning this but that is where that discussion ended. This is what Iām working on right now, I will post results if I have any.
Keep in mind, the prints that succeed are coming out perfectly, a few of the best prints I had with this printer was with Bambu PETG-CF. But this makes it impossible to print anything for more than a few hours without removing the buildup from the nozzle. Sometimes I get lucky and the blob just attaches to an outer wall or gets knocked down from the nozzle leaving only a little scar on the surface of the print, however if it attaches to an inner wall it makes the nozzle jump the next layer which leads to parts easily braking at that height.
Finally, MANY MANY MANY thanks to @3DTech, you are a champ and thanks for the many replies, long conversations and sharing your knowledge! @djeZo888 has some nice results and tips with PETG-CF as well, just click on his profile and look for his activity. Same goes for @Matt, he has amazing results with PETG-CF. Most of the bullet points are ideas mentioned in many threads (including this one), just thought I would collect the ones that helped a lot for my own sake and for anyone reading this.
If anyone suffering from this annoying issue finds a definitive solution, please donāt forget to share it so others can benefit from it as well.
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Now, that is a gorgeous print!!!
Well done!
Best,
Stu
I have the same issues. Yesterday evening I tried to print the āinfinity cubeā from thingiverse. I printed the same model some years ago using an Anet A8 and result was very clean. Unfortunately the yesterdayās print didnāt come good, and after 3 attempts, I put everything in trash bin. I have just printed some pieces with PAHT-CF and prints came very good, without any issues. But, with this PETG-CF thereās something strange. I attach below some pics (maybe the model isnāt good for this filament? Too many retractions and overhangs?)
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Is that grid infill? Sort of hard to see from that angle and differentiate from rectilinear
If it is grid infill, I again recommend rectilinear. Your print looks like your infill is being damaged as it prints, probably due to crossing, and then the PETG starts printing in the air which leads to bits on the printbed.
I print rectilinear 15% infill and it seems to be a good balance of 1. not crossing and 2. having enough support for a top layer
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Yes, I used grid infill at 15%.
Iāll try using your settings. But continue to seems strange, because itās a couple of years that I print PETG and only with this filament I found some problem. As I said in the previous post, with PAHT-CF I didnāt find this problem (also using grid infill at 15%, 2 walls and default speeds)
I am updating my config - I started using 255 temp instead of 265 for PETG-CF. I have also replaced the silicone sock with brand new one. So far, large print, 2h printing, no noticable buildup of filament on the nozzle. Looks good. Will post picture of the print when it is done.
Considerable less nozzle buildup, did not have to clean it during the print. Print lasted 3h. There was some buildup at the end, which I cleaned before next print. The print turned out perfect as you can see.
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Beautiful print! Congrats!!!