Liquid fuelled engines are throttleable and monstrously powerful, but highly complex. Meanwhile, solid rocket engines are simple and cheap, but once you light them, they’re going full-bore until burnout. Hybrid rocket engines offer perks from both worlds, with simple solid fuel and the ability to throttle down by regulating oxidizer flow. Naturally, [Integza] decided he should try and 3D print one.
The build came about somewhat by accident, as the 3D printed casing of one of [Integza’s] liquid-fuelled rockets continued burning once the fuel was turned off. This prompted the realization that he could 3D print rocket fuel, and simply supply oxygen, creating a hybrid rocket. Thus ensued much experimentation, going so far as to create custom sugar-loaded resin for more power and experimenting with ABS as a potential fuel.
Most of the rockets self-destructed within a few seconds and thrust was minimal, but the basic concept should be a goer. As always, [Integza] is struggling with the thermal limitations of plastics, but we fully expect he’ll one day get to a flight ready engine. His previous experiments show he certainly doesn’t give up. Video after the break.
The most fascinating thing to me about his work is that he does burning flaming rocketing experiments in an attic! I’m no safety warrior but I confess I find myself looking for the fire extinguisher. (And his presentation is pretty cool.)
I very much like Integza’s videos, that’s why I subscribe to him on YouTube, but if you guys are going to post every one of his videos as an article, maybe you need to make a new system where people can go check the recommended YouTube channels without them showing up in the news feed all the time. The first few times didn’t bother me, and I even speak out against all the complaining about YouTube videos, because good news is found where it’s found, but I feel this is a little different at this point.
Put your printer in a vacuum and print around an oxidizer like N03
We print ABS fuel grains for hybrids at USU.
Use a metal insert in yout nozzle. Or a real metal nozzle. It should perform much better
You can get blocks and rods of graphite on eBay for not much. It is easy to machine. I wonder how it would hold up.