Let me preface this post with a warning – rockets are dangerous. Please be extra careful if you even think about experimenting with them. Now onto the fun stuff…

With the exception of solid fuel model rockets, actual rocket engines have been out of the reach (and budget) of most DIY’s. However, there’s an older rocket technology called a pulse jet engine which is making a comeback amongst do it yourselvers. It was first invented by Germany and used in their notorious V-1 rockets (buzz bombs) in WWII. One reason they’re popular today is that they can be built with no moving parts. Here’s more info on how they work.

One of the simplest possible pulse jet engines can be made out of a standard jam jar. Make magazine (if you don’t already have a subcription I highly recommend it) has a great article on how to make one of these out of easy-to-find parts. Here’s a video of the jam jar project.

Jam jars are just the beginning however. Whole communities of modern day rocketeers are converging on sites like pulse-jets.com and jetzilla.com to discuss their engines and share designs. Like anything else, some people have taken these engines to extremes. They’ve even been used in RC planes.

Some have also tried creating their own turbine jet engines – while difficult to create from scratch, an automobile turbocharger can be modified for the purpose. Others are creating rockets which use a combination of tar and oxygen for fuel. These rockets tend to be quite powerful and this video gives an example of why you need a protective barrier when fooling with this stuff:

Thankfully they decided to add a protective shield around their rocket as they continued their later experiments.

For those who’d rather avoid the danger of fire and explosions. I suggest trying a water bottle rocket instead – basically, a 2L pop bottle pumped up to 70psi+ that can go about 80-100ft in the air. Here a video of the bottle rocket in action