Chocolate as rocket fuel

[Adric Menning] has an unfortunate allergy. He’s allergic to chocolate. Instead of eating the stuff, he’s using it to build model rocket engines. The project stems from the Quelab Hackerspace’s chocolate hacking challenge which spawned a number of interesting hacks. [Adric’s] doesn’t use pure chocolate (an experiment with a Hershey’s bar was a bust) but manages to ignite using a Milky Way bar.

This is not as unorthodox as you might think. Sugar and potassium nitrate have long been used to create solid rocket propellant. The chocolate version is swapping out plain old sugar for the candy bar. It was chopped into 10 gram chunks to make proportion calculations easier later on. The chunks go into the freezer to make them easier to grind using a mortar and pestle. Once it’s a somewhat chunk-free powder he mixes it with the potassium nitrate which previously had its own trip through the grinder. After being packed into a chunk of PVC pipe and fitted with an exhaust nozzle the engine is ready to go.

You can check out the test-fire video after the break. There’s a burn restriction in his area due to drought so this is just an engine test and not an actual rocket launch.

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Wedding gift fail has happy couple cursing your name

[Superluminal] received an invite to his friend’s wedding. He got together with some mutual acquaintances to take up a collection as a wedding gift. But as things go, a suitable present couldn’t be found. The pooled money itself ended up being the gift, but apparently a greeting card with a money pocket inside of it wasn’t good enough. The group decided to encase the coinage in a block of sugar that doubles as a lamp.

Now as with many well-meaning projects this started out with a rendering of what the final product would look like. That image came out great, with a high-gloss dark amber cube lit from the bottom with the coins suspended throughout catching a bit of a glint. They bought 43kg (almost 100 pounds) of refined sugar, and made a base/mold combination out of sheet metal. A lot of induction cooking went into producing thick syrup that could be poured into the mold. The problem is the final product is basically opaque. Not a sign of the 300 Euros within.

But don’t feel too bad for the groom and his bride. The image above shows him trying to get at the prize. He must do some hacking himself because he has a pressure washer, jack hammer (or is that big drill?), humongous cold chisel, and sizable hatch already at his disposal.

We can’t help but wonder if a heat gun could have polished the sides of the cube and helped add translucence?