The Next Layer Tests 16 Viral 3D-Printed Tools So You Don't Have To

A video roundup of viral functional prints

The Next Layer just published a video that should save you some filament. Jonathan Levi spends 29 minutes testing 16 of the most-shared 3D-printed tools and organizers on MakerWorld, and the results are mixed. About half the designs work as advertised. The other half are clever ideas that fall apart in real use.

The video covers a ModGrid pocket organizer, a low-profile Sheet Keeper for vinyl or paper storage, a CryoPod insulated can cooler, a volcano-shaped mosquito coil burner, a foldable pocket fan, a fruit fly trap called Flycatraz, a T-shaped returning boomerang, a bass tube instrument, an epoxy mixing pad with roller, a filament splicer, and a side-lace shoe lock. Each gets printed, handled, and judged on whether it earns a permanent spot on the desk or a trip to the scrap bin.

The ModGrid concept, a Gridfinity-inspired system scaled down for pockets and small parts bins, comes out well. Levi found the tolerances tight enough that the parts actually stack and separate cleanly. The CryoPod insulated can holder traps a small amount of water inside for evaporative cooling and does keep a beverage cold longer than an open container, though it is bulky. The Sheet Keeper is simple and effective if you print it in PETG or ASA; PLA will eventually warp in a humid workshop.

The portable pocket fan looks impressive but runs down quickly because the impeller design is not efficient enough for sustained airflow. The boomerang, meanwhile, actually returns. Levi notes that it only needs 14 minutes of print time and 18 grams of filament, making it one of the better odds against gravity in the batch.

The filament splicer is practical in theory but fiddly in practice. Getting a clean butt weld between two filament strands demands a consistent feed speed and a clean cut on both ends. Levi found that most users would get better results from a dedicated commercial splicer, but the printed version is cheap to try.

The shoe lock by Vinner's Lab 3D is a small clip that replaces the lace on slip-on sneakers, adding a ratcheting hold. Levi found it strong enough for casual walking but questioned whether it would survive daily use on running shoes. The universal hook by VC Design uses a deliberate infill orientation to concentrate strength where the load pulls, and it held up to Levi's weight in testing.

The epoxy mixing pad and roller are useful for anyone who works with resin or adhesive. The roller prints in place, uses no hardware, and the flexible TPU版本 works well for squeezing glue into corners without making a mess. The bass tube is a novelty instrument made from a nitrile glove membrane stretched over a 3D-printed frame. It produces a playable low note, but Levi warns that the sound will test relationships in shared living spaces.

The video is sponsored by AnyCubic's Kobra X, which Levi mentions mid-roll. The sponsorship is disclosed, and the review tone stays focused on the tested designs rather than drifting into the printer itself.

What this means for makers

The bigger takeaway is not the specific models. It is that viral functional prints need real-world testing before anyone commits to a long filament run. A design that looks smooth in a 10-second TikTok clip can fail at the first stress point. Levi's method, printing every candidate himself and using them around the house for a few days, is a reasonable filter.

If you want to try the winners, the STL files are linked in the video description on MakerWorld. Start with PETG or ABS for anything that carries load or sits in a warm car. PLA is fine for display pieces and short-term tests, but it will deform under the conditions many of these designs are meant for.