3D printer lessons
I’ve owned an Ender 3 for nearly a year now. I’ve had some elated highs and some dark lows.
Update your firmware NOW.
Assembly issues with cheaper printers can cause electrical fires, and some people have burnt their houses down. If your thermistor malfunctions, your printer will attempt to heat the hotend until it explodes or the plastic catches fire. This is why most firmware comes with thermal runaway protection. The Ender 3 does not! Update your firmware and enable this protection. I followed this video and used the recommended TH3D firmware. Now if your thermistor malfunctions, the printer will emergency stop, set temperatures to 0 and idle. This might be annoying if your thermisor malfunctions for a short period, but if this occurs, it’s time to check connections or replace it.
Buying a fire extinguisher and smoke / heat detector to store near the printer is also a wise move.
You will likely miscalibrate or damage your printer at some point due to impatience. You need patience to understand why problems are occurring. Impatient changes are more likely to cause you trouble than help, so avoid changing much while you’re also printing something. Intend your changes and execute them with a plan.
Obsess about absolute level.
There are many factors to consider when 3D printing, but the bed is the primary part to calibrate. While many parts can fail, the bed must remain stable and level throughout. If your bed is wobbling, shifting or failing to remain level, you need to verify your printer is correctly assembled and ensure that the bearings are fine. If one of your carriages are tilting or shifting, they’re likely too loose for the precison acts your printer performs.
Check every aspect of your printer briefly when your prints are failing.
After a roll of filament dropped on my Y axis, some screws loosened and introduced a slight wobble. Some rough treatment of the bed caused the metal bearings to rip through the plastic bearings to tea. Small assembly issues can result in mysterious issues that look like other problems when you research the symptoms.
Don’t be afraid of the hotend.
While it seems like a daunting piece of equipment, it’s only a few hunks of metal and screws. Heating it up and cleaning out out isn’t very difficult. Remember it’s a soft metal, so most other metals will dig into it. Only mess with screws and replacement nozzles while the hotend is above 175c and take care to reinstall the PTFE tubing firmly when reassembling the unit. If you get a leak from the nozzle, the PTFE tubing has come loose, and will need removing, trimming, and the excess plastic will need to be tweezered or otherwise shoved out of the hot end.
The borosciliate glass bed is good. Buy bigger bulldog clips.
I’ve never had bed adhesion problems that I could trace back to the glass bed. Usually I would have filament temperature issues. Your brass nozzle will yield first, so you might scratch it a little but your nozzle is worse off. Speaking of which…
Buy a few extra nozzles.
It’s likely you’ll damage the nozzle’s nose at some point. Your tool will slip, you’ll make a Marlin command error, your printer will use the relative movement after you issue an absolute movement command… I was reluctant to change mine for some time, but after a few early mistakes I realised that I could sometimes be calibrating a bed around a seriously damaged nozzle, to no good effect.
Running back and forth with an SD card, forgetting it at one end or the other and being unable to queue prints unless you have multiple SD cards will be frustrating. Install OctoPrint on a spare Raspberry Pi, and prefer a higher quality SD card where possible. The Ender 3 does stutter quite poorly without firmware changes, so I recommend you either upgrade the motherboard or get used to SD card juggling for very fine prints (miniatures, high curve models).
Don’t store your plastic in the bathroom.
Filament is moisture sensitive. My printer is in a sometimes damp environment. People recomend convection ovens or dehydrators to dry filament. You can use central heating radiators if you rotate the reel occasionally. I have a temperature and moisture sensor to warn me if my humidity is too high.
Enjoy yourself, it’s a hobby
Don’t take it too seriously! Buy this thing expecting to spend a little more money on it, but also expect to find a lot of joyous things to cut your teeth on. Now you need to learn how to edit and create your own 3D models, your own things to cast into 3D. If you feel yourself getting frustrated, put it down. I once stopped printing for 3 months, because the stress from multiple issues was driving me up the wall. I returned with a fresh perspective and a good attitude, and I had my printer running well within days. Take a break. Make it fun again.