I’m trying to create a small, flat keychain for someone, but it won’t stick to the bed. Eventually it will let go at the edges even when I create a brim ( even tried a large one, heck even tried a skirt ! ) but it won’t help it stay attached. I even use an adhesion stick.
Then, even some doll slippers that printed just fine twice, suddenly decided that it didn’t want to stick anymore. I got the printer in yesterday, I’ve only done a hand full of prints so far, it still has all the default things on it and whatnpt.
The first recommendation is to clean the build surface. The method is usually divided into two camps. Water and detergent or alcohol. Either works, hot water with detergent and a good rinse is what Bambu recommends. Alcohol also works but it’s more than just a simple wipe and go. If you just give it a quick wipe, you have dissolved the gunk and evenly spread it across the plate. You need to use enough alcohol to leave it damp and immediately wipe it with a clean towel to remove the dissolved gunk. I sometimes go for a third wipe if I feel it was pretty dirty. This method comes from my 6 years in the CD replication industry.
Another thing to look at is to check if your nozzle is bent. It can be fairly subtle. If it’s bent, first layer adhesion can be weak.
Check the tip of the nozzle, if it has any build up on it, it will throw off the zeroing process.
To check for both of these things, it may be easier to remove the hot end so that you can look at all sides. This wiki shows how to remove the hot end. There are way more steps here than you may need as it goes into stripping down the assembly and all you want is a good look at the joint between the heat sink and the small diameter tube. This is where it usually bends.
In the case of temperatures - would this be a matter of “too hot” or “too cold” to your knowledge?
The edges seem to curl up a bit as the filament cools / hardens, if that helps.
The answer is complicated but one video that does a good job of explaining the whys is this one.
He’s being a bit of dick here in not explaining how to fix it but I can tell you that if one wants to master 3D printing then one has to first master the concepts of troubleshooting 101.
One of the best classes I took in college was Experimentation 101 which was grounded in scientific method. That and expository writing were arguably the only two truly useful classes that I still use throughout my life. Here is my top list of troubleshooting techniques gained over years of engineering experimentation and design. These apply to everything from troubleshooting to cooking.
First, try to create a test scenario with the fewest variables that can demonstrate the problem in a repeatable way. In 3D printing, that often comes down to cutting the model into sections until you find the smallest section that can reproduce the error.
Change one variable at a time. This is one of those “Duh… that’s obvious” but 99% of us have tried to cheat and take shortcuts by changing more than one thing at a time.
When creating experimental test scenarios, use widely varying parameters. So to answer you question, too hot or too cold? Simply create your scenario and test at the extremes and in the middle and you will find your answer.
Do not believe anything tells you especially people you trust. Always test and test again. Verify for yourself and create test scenarios that you can repeat. If you get it right the first time, you almost certainly got it wrong and are just lucky but you have also conned yourself into believing you found the problem.
While I agree that #4 comes across as pessimistic, that’s because it is. Between Scientists, Engineers and most of all, Doctors, if there is one thing I learned is that the more someone tells you they “Know what they are talking about” the least likely it is that they do. That’s not to say that they may not be wrong but as the saying goes “even a broken clock is correct twice a day”.
I hope my answer isn’t coming across smarmy. What I am trying to do is rather than give you my opinion, which can only go so far since I am not in front of the machine, I am trying to share how I would diagnose the problem if I were sitting in front of the machine.
Now last, if you can’t break down the problem into discrete components and it appears to be happening randomly, then the only way I know is through direct observation over time. To that end, I’ve actually created a camera setup using an ESP32 wireless unit with customized software that takes time lapsed photos under specific head movement positions. This think is a true science project to say the least but that combined with tying temperature sensors to key sections of the printer have been the only way I have found to truly diagnose elusive problems. And sometimes I walk away with “WTF… who would have imagined that was the issue?” moment.
