My 3 Most Common 3D Printing Problems (and How I Fix Them).
Fun, Most of the Time
3D printers, when they work, sometimes seem like magic. They're mesmerizing to watch in the way they seemingly create something from nothing. On occasion though, there are times when your printer just doesn't seem to want to work with you. Fortunately there is often a relatively easy fix available depending on the issue.
The most common 3D printer issues that I experience at home include having the first layer not stick, weak infill or inconsistent layers, and sometimes having prints that are too big. While they are all very different types of issues, there are things you can to do help improve and fix each one.
This article is a little personal in the sense that I'm going to cover issues that I seem to come across fairly often on my own machine, a Wanhao Duplicator i3. Your common issues may be different, but hopefully some of this advice will still guide you to a fix. Based on my online research, it seems like these issues are fairly common for other as well.
Problem 1: The first layer isn't sticking.
This issue is probably my biggest single frustration at times. One day my printer seems to be working just fine and then seemingly out of nowhere I can't get any print to start off cleanly. The filament either seems to not stick at all, or it gets too squished and causes ripples in the base layer that eventually turn in to a failed print. In some instances one edge of the model will start peeling up or get caught on the extruder which if left unattended, turns into a big blob of plastic on the end of my extruder and can take some time to clean up.
Over time though, I've learned to deal with this issue pretty well. There are still occasional times when I just want to do a quick print and the machine doesn't seem to want to cooperate, but by doing the following troubleshooting I have been able to keep my success rate high.
First and foremost, bed cleanliness and preparation is key.
I make sure that the printer bed is clean and that I have applied some type of light adhesive. If you look online you will see that some people use things like blue painter's tape or a glue stick. My favorite trick is using extra firm hold hairspray (Aquanet if anyone is wondering). Before I turn the printer on, but after I clean the bed, I apply a couple lights sprays of hairspray to the printing surface. This provides a slightly sticky layer that the print can stick to. This plus the clean bed really seems to work wonders for me personally. (Side note, I'm not sure if it's actually an issue, but I am always careful to keep the hairspray focused on the bed. There is a possibility that spraying a big cloud on your machine can build-up over time and cause some sticking issues with gears or sliders that you probably won't want to deal with, so spray carefully!) Also, make sure the hairspray dries before starting a print, otherwise nothing will stick!
Leveling the bed.
If putting some hairspray down doesn't work then I move on to work on leveling the printer bed. For those who have spent some time leveling their printer, this can be one of the more frustrating tasks.
Basically, to level the printer you make sure that the Z axis is home (use the "home" feature on your printer). Then you move the print head around the bed and make sure there is just enough space to slide a single piece of paper in between extruder nozzle and the printer bed. The best way I founded you this is to start at all four corners, make adjustments and then start checking random spots around the bed before going back to the four corners one last time. If the paper fits evenly under the bed at all locations you've tested, you're probably in good shape!
The most important thing to say about this process is to be patient! Most of the time when my bed leveling doesn't seem to do the trick, it's usually because I'm in a rush. It's a work night and I'm trying to get a short print done before I go to bed. what I really should be doing though is just focus on leveling the bed properly. I would say it only takes about 15 to 20 minutes of focused effort to get things set perfectly.
Where I run into problems is I try and level it in about 2 minutes and then start the print again to see if it works. This usually leads to multiple false starts and leveling over and over again. I sometimes feel like I waste hours when, if I had just spent my evening focused on the task at hand, I could have been over and done with it in my printer would be ready for me to print perfectly the next evening!
Problem 2: My infill is weak or my layers don't quite seem consistent.
There are a few different reasons for this type of problem, one of them being your temperature and speed settings. The above photo for example, used exactly the same settings for both prints except for one key element, the filament diameter setting. By accident, the model on the left was set to a 3MM filament when my printer is actually supposed to be 1.75MM. You can see what one small checkbox can do to make the quality jump up!
That said, if you have already done some troubleshooting or you know that the filament you are using should be working fine with the current settings you have, you may have a clogged nozzle on your hands.
Clogged printer nozzles can definitely cause some headaches. It's not something that you often think about because it can seem like your filament is flowing freely if you're just watching it shoot out of the nozzle. In reality there could be a stuck piece of filament that is introducing occasional inconsistencies in your feed rate which ends up affecting your end print.
The best way to deal with this is to complete what's called a "cold pull". There are many tutorials online on how to do this but in short you feed a small amount of filament through the nozzle and you let the printer cool down. Once it's cool you pull the piece of filament back out with some force. Ideally, the piece of filament solidifies in the extruder nozzle and when you pull it out it takes the clog with it. You may have to do this a couple times but once you're comfortable with the procedure, it doesn't take long. Even if it takes a few tries over an afternoon, the results are usually worth it.
Problem 3: My print is too big!
This is not so much a problem as it is just a general fact of 3D printing. It is slow! Often when I'm working on a project, I decide that I want to make something big. this means that I run into a couple of problems though.
One is the obvious fact that my printer is relatively small and some things just won't fit. The second issue however is the fact that even if I can max out my printer size, the print will usually take an extremely long time, sometimes 24 hours or more!
For safety reasons, there have been occasions where I will schedule an all-nighter so I can be around to monitor my print safely, but most of the time that's just not practical the vast majority of the time.
My solution? Cut the model into smaller pieces and reassemble them once they're printed (there are a lot of methods, I personally like hot glue).
It sounds challenging for those without experience, but in reality is not that bad if you have the right tools. For simple model cutting, I use Tinkercad. It's a completely free online tool and is fairly easy to use once you get the hang of it.
The basic idea is that to load the model you are looking to split up, delete a portion of it using the "combine" feature with a "hole" that cuts the model where you set.
When slicing the model into smaller portions, try to find break points that make sense. Usually it's possible to find some kind of a seam that when you glue your model together later won't make it so obvious that it's multiple pieces.
Conclusion
Hopefully taking a look at these few problems that I run into often have given you some ideas on how to solve them for yourself. There are a ton of tutorials online to help fix a myriad of issues when it comes to 3D printing. But I have found that becoming familiar with these three problems and learning how to deal with them in the way that I've laid out can really help increase the utility of a home 3D printer.