DIY Jet Engine Erupts in Flames Before Melting Its Own Internals
The ambition was admirable: a small-scale jet engine designed from the ground up so that ordinary makers, with no specialist equipment, could replicate it. The result was also instructive – just not in the way the creator intended.
The whole journey – from building the engine to setting up an outdoor test to the dramatic meltdown – is captured in a single video. The builder, AydenWardell Aerospace , shaped metal housing components by hand with a hammer, mounted a bright green 3D-printed compressor fan inside a blue plastic cowling, and rigged up a four-channel temperature sensor array to monitor the run. Proper safety kit – glasses, ear protection, gloves – was on. The engine, at least visually, looked the part.
Then they lit it.
The Engine Almost Worked, Which Made It Worse
"This engine went together rather well, but upon testing, it had a major issue: it did not easily self-sustain. It was almost there, but it never quite made it," the creator narrates. You can hear the compressor spool up on the footage, the pitch climbing as RPM builds – and then the moment the starter motor cuts out, the whole thing deflates. "You can hear how the RPM increases, but as soon as the starter motor is taken away, it dramatically falls again," they explain.
That gap between almost and actually is the central engineering problem with small DIY turbojets. For an engine to run without external help, the turbine has to drive the compressor hard enough to sustain combustion on its own – a threshold that, per Hackaday's coverage of hobbyist jet builds going back to 2016 , many home-built attempts never cross. Without that self-sustaining loop, you essentially have a very expensive , very loud blowtorch.
The second problem compounded the first. Excess fuel was pumping into the combustion chamber, generating heat the structure simply couldn't absorb. The exhaust cone glowed cherry red. Temperature sensors tracked the top reading surging past 174°C and the lower sensor climbing from 117°C to nearly 137°C within the test window. "Also, the fuel was too excessive. So, the heat caused also major problems ," the creator says.
For the 3D-printed compressor fan, those numbers were a death sentence. ABS filament – one of the more heat-tolerant common printing materials – begins to soften around 100°C, per Hackaday's materials reporting. Whatever plastic went into this fan didn't survive long past that point. "Eventually, the 3D-printed parts melted through, causing the engine to jam up," the creator confirms. Video captured after the test reveals the compressor had been deformed into a twisted, vitrified lump, melted onto the metal collet at its core.
"You can see how hot this gets, with the maximum temperature being well over 100° Celsius. The 3D-printed parts could not handle this at all, and were destroyed by the heat."
Plastic and Combustion Have Never Really Gotten Along
This outcome is painful, but it isn't surprising. Hackaday's coverage of a May 2026 water-cooled 3D-printed rocket project found the same wall: even with active cooling designed into the system, the combustion chamber melted almost immediately, and a subsequent redesign eventually failed when the water jacket began leaking into the chamber. Molten plastic was visible dripping from the nozzle shortly after ignition.
The physics tell us why. Plastic's thermal conductivity is far too low for the heat flux that combustion environments generate, and any wall thin enough to actually conduct heat away would have no structural integrity left. Metal handles the thermal load because it conducts heat rapidly and maintains strength at temperatures that liquefy common filaments. Builders who have coaxed DIY turbojets into sustained operation have, almost without exception, kept 3D printing strictly away from the hot section – compressor housings and aerodynamic fairings only, with turbine, shaft, bearings, and combustion chamber all in metal.
None of that diminishes what this builder tried. A jet engine you could fabricate with standard tools is a genuinely interesting engineering target, and the construction itself apparently held up. The problem is that the compressor fan lives right in the path of combustion backwash, and no common printing material survives that for long. The next version of this engine probably needs a machined or cast metal fan – which does rather complicate the "anyone with regular tools" idea, but that's the tradeoff combustion physics insists on.
