5 beginner 3D printing mistakes that will cost you a whole spool of filament

Credit: Tim Brookes / How-To Geek Published Jul 19, 2026, 7:00 AM EDT Tim has been covering technology for almost 20 years, in that time spanning a broad range of topics from security to product reviews. He is especially focused on the Apple ecosystem, productivity, and consumer advice. Over the years Tim has written thousands of articles, reviews, and round-ups in addition to producing video content and original photography. A graduate of journalism, he found his footing as a freelancer with a laptop and loves how he is able to work from practically anywhere. Now a Senior Editor for iPhone, Mac, and Smart Home at How-To Geek, Tim still loves to write. He can also be found crafting round-ups and productivity posts for the Zapier blog. Earlier in his career Tim spent nearly a decade as a writer and eventually Apple section editor for MakeUseOf. Tim currently lives in Brisbane, Australia. Outside of work he loves to hike and work out, play video games, and spend quality time with his wonderful partner and two cats Inka and Roger. Basic 3D printing filament is relatively affordable, but nobody likes wasting their money. Avoiding disaster requires that you not fall into the trap of making rookie mistakes. Knowing what these are can save you filament, money, and time. Here are some things you should avoid doing. Bambu Lab PLA Basic Filament Bambu Lab's PLA Basic filament comes in a wide range of colors and ships on a reusable plastic spool. With embedded RFID chips in each spool, you simply place the filament in the AMS and your 3D printer knows exactly what it's working with—down to the color. Mishandling the spool so that it unravels Respooling is possible but tedious Credit: Joe Fedewa / How-To Geek I’ve lost track of how many Reddit posts that include a photo of an unraveled spool of filament and a “how do I fix this” caption. I’m also a bit paranoid about having it happen to me, which is why I’m always very careful when loading and unloading spools. Whenever you dry your spools in a rotating filament dryer, make sure you tuck the filament end into the holes on the spool itself. Alternatively, grab some filament clips that allow the spool to rotate freely (and use them whenever you store your filament). Lastly, be careful not to allow the spool to unscrew from the center (which it is designed to do so that you can use it for refills). If you drop a spool and the whole thing turns into a mess of spaghetti, you can attempt to recover it with a filament respooler (but the process is time-consuming and best avoided). Not drying your filament before using it Poor quality 3D prints mean wasted filament Credit: Tim Brookes / How-To Geek I’m a strong believer in always drying your filament out before you use it, even if it’s just regular old PLA. Moisture can ruin your 3D prints by causing layer adhesion issues, stringing, uneven surfaces, and total print failures. Not everyone shares my opinion, but I don’t print that often, so setting off a drying cycle isn’t too much of a hassle for me. When it comes to more challenging filament types like PETG, ABS, ASA, and other engineering filaments, drying is a no-brainer. You’ve spent good money on more durable and specialized filament; why not take a few hours to dry it out overnight? Drying at the wrong temperature Pay attention to the glass transition temperature This is another mistake I’ve seen people make that I have thankfully avoided, mostly due to my preference for PLA. The glass transition temperature of a material is the point at which it begins to deform (melting temperature, the point at which it turns to liquid, is a lot higher). For PLA, this is around 65ºC, which is why PLA must be dried at around 45ºC—hot enough to evaporate moisture stored in the filament, low enough to avoid the filament deforming. Different filaments have higher glass transition temperatures, which means they can be dried at higher temperatures. If you make a mistake and dry PLA at around 65ºC, you’ll end up fusing the whole roll together into one solid chunk. Since most dryers have hot spots, even 50 or 55ºC is a risk. Using PLA spools for PETG (or other filament types) Your spools need to withstand your drying temperatures Credit: Patrick Campanale / How-To Geek You can 3D print your own spools, which is handy if you end up buying filament refills that lack a spool. Refills are cheaper, but a spool is still necessary for safe mounting of the filament. The cheapest spools are made from the cheapest material, which just happens to be PLA. This is fine if you’re drying PLA on a PLA spool. But if you’re using PETG or ABS (or material that requires a higher drying temperature), you should avoid using a PLA spool. The spool will deform at higher temperatures, potentially fusing to your fresh filament or causing it to come off the spool and unravel into a spaghetti monster on the floor. Even if you can rescue the filament, the spool is ruined and any filament you used to make it is wasted. Repeating the same mistakes without making changes Do you know the definition of insanity? Credit: Tim Brookes / How-To Geek It sucks when a print fails, and you don’t know why. There can be many causes: “wet” filament, a greasy print bed, dodgy slicer settings, blockages in the nozzle, even just a “bad” model file. One thing you definitely shouldn’t do is make no changes and stick the model on to print again, immediately after it fails, assuming that it was just bad luck. I prefer to stack the odds in my favor by eliminating as many possible points of failure as possible, even though this means that I’ll never know why the failure happened. Start by cleaning your print bed and checking moisture levels in your filament. If you don’t have an AMS or similar system with a hygrometer, consider a “quick” six-hour dry cycle anyway. Make sure that your slicer settings are correct, too. Do you have the “right” nozzle type selected? Does your slicer know which filament is loaded? Have you enabled supports for overhanging areas? If you downloaded the model, check the reviews to make sure nobody else has the same problem as you. If the model fails twice, and you’ve done all you can, it might be time to find another. Bambu Lab AMS 2 Pro A multi-material system for Bambu Lab printers with active air vent 65°C filament drying, air-tight filament storage, a brushless servo feeding motor, Bambu's signature RFID filament sync, and compatibility with up to up 24-color/material printing by connecting more AMS 2 Pro units. Whatever you do, sometimes prints just fail. To offset your losses, here are a few ways to save money on filament.