3d printers are machines, and as such, work best if properly maintained once in a while. So what do you need to check, and how do you identify problems and fix them? We’ll look at several basic things to watch for and fixes you can do to keep your machine in good working order. Properly tuned in this way, not only will you get good prints, you’ll get hassle-free prints (most of the time!)
Ensure that dust, hairs and lint are clear of any fans. Ensure belts are tightened. Ensure no melted filament is built up around the hot end. Ensure that the feed gears are clean and not worn or clogged. Cleaning and tightening these issues is all that is generally required for good running for your Ender 3.
Cleaning and adjusting can take as little as 10 minutes once a month or so, and you’ll find that your Ender 3 runs well for a good long time. You will avoid more costly repairs or parts replacements if you check these simple items, and your investment in a good 3d printer will continue to be a good one moving forward.
Check the Ender 3’s X and Y Belts
For the Ender 3’s X and Y axes, you’ll want to check the tension on the belts that move the print head left and right, and the heated bed back and forth. The up and down motion is not governed by a belt, but instead uses a worm gear. The belts for X and Y should be tight like a guitar string. They should “twang” when you pluck them.
To test them, take the larger Allen key that came with the printer, and pluck the belt. Does the belt sag or not seem tight? It’s likely time to tighten it. Tightening is rather simple. There are two locking bolts that hold the tension wheel in place. Loosen these. You’ll find that the belt is very saggy now. To tighten, use a pliers or another Allen wrench and pry back the wheel until it tensions the belt rather tightly. Now, while under tension, tighten those two bolts to keep the wheel in the tensioned state. It’s as simple as that.
Do the same for both the X and the Y belts, if they need them. Twang them first. If they’re already tight, ignore them. If they need adjusting, do so. If you find that you adjusted them but that they’re still loose, you may need an extra set of hands to help. One person can tension back the wheel while the other tightens the bolts. If it doesn’t work the first time, try again.
With a well adjusted set of belts, you will find that your prints have less pattern on smooth surfaces. The quality of the print will be a little bit better, and that’s always a good thing!
Clean Out Ender 3’s Dusty Fans
There are two fans on the shroud around the hot end of the Ender 3. Power off the Ender 3. Remove the two mount bolts on the shroud, and carefully move it back to reveal the inside of the shroud. I use a tweezers to remove dust and cat hair from inside and on the fan blades. I have cats, so it’s not uncommon to have some cat hairs lurking in there. A can of compressed air (used for computer and keyboard cleaning) can really help as well.
Turn on the power and watch the fans spin up. If there’s any new material, turn off the printer and clean the newly revealed material out. Then replace the fan shroud by putting the two bolts back in. Ensure that you don’t twist, pinch or tension the power cables. You should hear no foreign object noise from the fans when you power on the printer (and the fans) with the shroud replaced.
There’s a fan underneath the cover of the enclosure for the main logic board for the Ender 3. Again, turn off the power and remove the cover. This can be more difficult, as you’ll have to remove the bed from its bolts and raise it to get to the back screw for the cover. Unfortunately, that means that when you reassemble, you’ll have to relevel the print bed.
Instead, use your compressed air can and air out the fan opening to blow out any obvious debris. Print a fan cover to protect against anything falling down from the print bed or in from around the print bed. I mentioned this mod in the article on Ender 3 modifications here:
The catch-22 of this mod is that you need to have a working printer to print the mod in the first place! Once you’ve printed the fan cover, attach it with the same two front screws that hold the enclosure closed. Once in place, stuff falling from the print bed (like bits of filament) or dust bunnies won’t end up falling into the fan. The fan blows upwards, so dust should be blown out.
Check For Melted Filament Around Ender 3’s Hot End
When you’ve got the fan shroud off the hot end when you’re checking the fans, have a look at the hot end itself. You may find that you have a buildup of melted filament from a jam or problem caked around the hot end. It may be easiest to remove this with a small toothpick once the hot end is up around 200°C. The offending molten filament is soft (but very hot, so be careful). Scrape away any residue and then power down the printer. Let the hot end cool before reassembling everything.
If you find that the Bowden filament feed tube is somehow damaged, this would be a good time to replace that too. The same article linked to above has a link to a kit for replacing both the tube and the two connectors.
Inspect the Feed Gears on the Ender 3
The way an Ender 3 works is to force filament into the hot end, where it’s extruded through the nozzle. For that to happen, the feed mechanism needs to be in good repair. If you ever hear a “clunk, clunk” sound from the feed, watch it. It may be revealing that something is clogged ahead in the hot end, not allowing filament to be fed in.
But you may not be around if this occurs. It may occur 19 hours into a 22 hour print! If so, you may find a failed print, but worse, you may find that raw filament has been ground into the gear teeth of the feed mechanism on the left side of the printer. You can visually inspect this gear without disassembling it. If it looks like brass, and clean of plastic residue, then you’re good. If it has residue, then you may need to use a probe to try and dislodge the material.
If it’s really fouled, you may consider disassembling to get a better angle to clean the gears, or even replace them with a new feed mechanism. Here’s a link for a replacement. You can upgrade to even better models, but this one is equivalent to the original feed mechanism:
With a simple set of checks, once a month, and a minor amount of corrective action, you’ll keep your Ender 3 printing for a long time into the future. Better some simple maintenance than an expensive repair or replace!
How do you change the nozzle on an Ender 3?
The nozzle is a screw fit on the bottom of the hot end. Either use the supplied or your own wrench (spanner) and untighten the nozzle. If it’s hot, let it fall away. Don’t try to grab or hold it, for fear of burning yourself. Once removed, you can either clean the nozzle or use a fresh replacement nozzle and screw it back in. Again, be careful if the hot end is heating, so that you do not burn yourself. Tighten with the same wrench (spanner).
How do I clean my Ender 3 nozzle?
The recommended way to clean out an Ender 3 nozzle is to heat it up, then, using a wooden cocktail stick or toothpick, push out or pick out any remaining melted filament. I, instead, just replace the nozzle with a fresh 0.4mm nozzle. They’re cheap on Amazon.Com for bunches of them, so I buy replacements and use them instead. The other reliable method is to remove the filament, then heat the nozzle to the maximum on the Ender 3, and leave it to drip clean over a period of five to ten minutes, then reload filament.