stan_bulgaria

Yes, problem solved. Where do I have to mark the topic as Solved?

Thank you for your reply gr5, To my last project I've noticed what you describe - on the raft and initial three layers the fan speed was 0 rpm (in Cura I specify in % of the max fan speed - 255 rpm). After that it goes to the specified - in the case 80%. On my other project with bridging the fan speed changes like this: - initial layer - 0 rpm; specified 80% - second layer - 128 rpm (50%); specified 80% - third layer - 204 rpm (80% as specified) - first layer of bridging - as specified 80% for the none hanging part and 99% as specified in the Experimental settings>Bridging - second layer of bridging - as specified 80% for the none hanging part and 0% of the hanging. - third and forth layer of bridging - same as the second one - fifth layer of bridging is all at 80% as specified. And after following your advice to write "FAN" in the search bar, I found the reason for all the above - hidden settings for me 🙂 Attached are pictures for all the points. Thanks for the help gr5. Regards Stan

Hello community, I have a question - What are the settings that control/affect the Fan speed in Cura? I have started a topic about the "Bridge fan speed" to which I don't have an answer and now I see that the fan speed for other projects I'm doing is not what I specify. Apparently there are some settings that are not stright forward visible or some Material, Shell or Other settings that affect the Fan speed. Thanks Stan

Hello community, I would like to understand what and how I specified in the settings to get the result I have. This time I've uploaded a video in youtube, so it can be seen what happens in reality. I went through the settings that I made but I don't see anything for the fan beside in COOLING (specified at 80%) and in EXPERIMENTAL> BRIDGE FAN SPEED (specified at 99%). In the general settings for "Manage materials" I have 100% fan speed. Situation: At layer 15 starts the bridging. The non hanging parts of the layer are printed as it should with the specified settings. Then starts the bridging, which is made to the settings - lower print speed and max fan (not very good result but satisfying for the project). Layer 16 - starts as specified on non hanging parts. When over the bridging part the print speed is lowered and fan speed goes to 0%! Layer 17 same as layer 16. Layer 18 same as layer 16. Layer 19 same as layer 16. Layer 20 all parts are at the specified settings. Why??? Another one thing I've noticed. At the initial - first layer, I normally am tuning manually the fan speed to 0% in order to have better bed bonding. However with this project the stringing in the initial layer was big, so with the last print I tuned the fan speed to 20% manually on the printer. To my surprise when the printing started, the printer corrected the fan speed to 0%! What am I doing so to have this fan speed changes? How to control them? Attached are: - the last settings for the project. - the gcode. - the link to the video. Thank you for your time. Regards Stan Dograma podlozhka.3mf Dograma podlozhka.gcode

Hi Friedl, unfortunately with so many filament and printer producers, plus local weather conditions that can play a role, it is difficult to have universal temperature settings for a type of material. As more complex the polymers are more things affect the printing result. But finding the correct settings once, after that it is fine tuning. Just an idea. Try to set each setting one by one - first try the bed temperature. When you are satisfied with it do the step by stem setting of the nozzle temperature. Regards Stan

Attached are the pictures of the finished detail. The filament is transparent and it is difficult to see on picture, but there is severe sagging from one of the sides. One more thing that I saw on layer 15. The printing of the openings is in a random order. It starts on the first opening from the middle of the wall towards the center; then the nozzle goes to the second opening and starts from the outer diameter toward the inner side (it starts in the air - it is visible if looking from down up); on the third opening it copies the moves of the first one. After that the print continues again in the air for the first and third openings. I did not check "Outer before inner walls" box. So what the print order should be - first inner walls and going toward the outer ones or it is a random order? If the "Outer before inner walls" box is checked the print order is from inner toward the outer diameter of the openings. However on the top layers where the overhangs are at 30 degrees the print starts from outer side which here is in the air! Regards Stan

Hello community, I've started a model which has some overhangs - 21 mm to be bridged. To do this I used the Bridge settings under Experimental tab in Cura 4.8.0. Where comes an issue? I watched how the bridge printing will be done on the printer and to my surprise I saw an opposite action to what I specified in Cura. Under "Bridge Fan Speed" I've set 100% but in reality the printer - Creality Ender 3 V2, is stopping the fan just before it starts the bridging and after finished with the bridging is going to the specified 80% for the rest of the layer, which is not overhang. It did this with the initial overhang layer and the rest 2 above it. Not to mention the result is disaster but it managed to fill the gap - it is still printing and I don't know how bad it looks from below. I'll attach a picture when it finish. My question is looking at my settings in the attached project file, why the fan is stoping when it has to be at full speed? Regards Stan Dograma podlozhka.3mf

Hello Friedl, apologizes for not answering on time - I just saw your question. My experience is very limited. I'm using two types of CPE (PETG modified) filaments. For harsh conditions I prefer Fillamentum CPE HG100 and for normal use RAST 3D PETG. In general I found out that for my printer Creality Ender 3 V2, the temperature settings are lower than the respective filament recommended. 1. So in order to find the most appropriate temperature settings I make a test to see at what temperature the filament starts flowing freely out of the nozzle. 2. Then I make a test what is the best temperature for the bed - go with increment of 5 degrees. In some of the filament TDS it is recommended bed temperature of 105 degrees. For me 75 was perfect and above 80 debonding was higher than below 70 - funny. 3. Then when the temperatures were set and the printing started another phenomenon appeared - just like with your detail, mine stared debonding from the bed (may be 2 hours after the print started). I understood I have skiped un important step - bed adhesion. Here in the forum is a very extensive topic about bed adhesion. Mine solution was hair spray on bare glass. Yes, I tried the salty water and the wood glue solution, but so far the hair spray and CPE HG100 or RAST 3D PETG work best together. 4. To make the adhesion even better on the initial layer I don't use fan at all. This has a bad result if your initial layer is a flat surface as you'll get blobs or warps, but normally the next layer will hide that imperfections. 5. For the shell details, like the rectangular pipe you want to print, I use raft to enhanse the adhesion to the bed. You'll use extra time and material but the deformations that may accure will be less. I attached two of my projects so you can see my settings. On Dograma... project I have some issue for which I'll open a new topic. I hope this information can be of help to you. Regards Stan Dograma podlozhka.3mf Anemometer4 final.3mf

I hope you have solved the issue already. One more thing I forgot. When I print the raft - the first 4 layers, I don't use the fan. I switch it off from the fine tuning of the printer. Starting from the fifth layer the fan gradually gets to the working speed - in my case 205 rpm.

I think you need lower bed T - 90C may be quite a lot. 70C would be more safe. However every filament is different.

I forgot one thing - I don't dry the filaments, if makes any difference. The humidity in the room I print is around 50%+-5, air temperature 18-20C.

My experience with CPE. After I finished the test PLA that came with my Ender 3 V2 I print only CPE - from two different producers and different colours. It took me almost one month to set the correct temperatures. 1. Here in the forum is described how to prepare the bed. In my case I cleaned the bare glass and sprayed it with hair spray - very light. That was before may be 16-17 prints. I haven't cleaned it or sprayed it again ever since. The models are sticking perfectly (I was surprised with the last as it is air plane tale without support, only raft). 2. Check the correct temperature at which the filament starts to freely go out of the nozzle. In my case the factory suggested T was 255-275C. It appeared the material starts flowing at 205 C. I print with it at 225 and when I want stronger bond 235C. The other colors print at 205-210. So make a test for the correct temperature. Otherwise you'll have blobs and huge stringing in layers above. 3. Bed temperature - same as point 2. After trials from 60 to 90 C it appeared for me 70-75 C is correct. In fact my first layers are perfect compared to the ones above. At T above 80C de-bonding is very easy. On your pictures it looks like the material was "boiling" or the glue evaporated and made bubbles. This is why your nozzle is dirty. At the beginning my nozzle was also picking a lot of material. Play with the temperature. Good luck.

I looked in the settings of my print settings. I have made visible "Make Overhang Printable", but it is not switched on. The description when the cursor is over it is clear.

Hello Blackgun, I'm using Creality Ender 3 V2 on OpenSUSE Leap 15.2 with Cura 4.8.0. I opened your project and sliced it as it is, so it has only 2 hours and 23 min estimated printing. But it is missing the hole in the bottom. However all the rest is present. I turned the detail to lay on one side. It has the holes that were missing but now the hole that appears on the bottom is missing. So the issue may be connected with the initial layers. I switched off the infill colors to see better the inprints/holes.

Hello Torgeir, good idea. It worths a trial and I'll check it when printing shells again. For the moment I have overcome the problem as I changed the model and inserted a support for the shell as Geert advised, with a very small gap of only 0,2 mm. In that way the surface covered by the support is good and has some blobs only around the edges. It is easy to remove the blobs afterwards even with finger. I've already broken two of the finished models and I've noticed something, which perhaps cannot be skipped. The detail body consists of three cylinders with different sizes. The connection between the cylinders is a weak point. That's because the cutting plane is parallel to the layers surface. I'm not sure if rising the temperature of the nozzle only for that 2-3 layers would do any difference. On one hand the higher temperature should stick the layers probably stronger but the material will be more rigid and not flexible at that plane. So at sudden start of rotation again can happen a debonding/cutting. I believe that is a major question and has to do with the producers of the filaments. Regards Stan