When it comes to weird and wacky homebrew rocket experiments, [Integza] keeps himself fairly busy. He’s now attempted a design repurposing Devil’s Toothpaste for propulsion.
Devil’s Toothpaste is really the same as the famous Elephant Toothpaste experiment, just executed with higher concentration hydrogen peroxide. In this case, [Integza] is using 50% hydrogen peroxide combined with potassium permanganate as a catalyst. When the two are combined, the hydrogen peroxide breaks down into oxygen and water, which [Integza] uses here to propel a skateboard.
The potassium permanganate catalyst is impregnated into 3D printed porous ceramic parts. The peroxide is then injected into this matrix via a compressed air mechanism, where it decomposes, creating a jet of water and oxygen that then blasts out of a 3D printed rocket nozzle to generate thrust.
It works surprisingly well, even if it’s a messy and unconventional way to build a rocket. It’s also a lot less fiery than most of [Integza]’s previous projects. Video after the break.
He’s still trying to use plastic for parts that need to be metal, like the nozzle mounting flange. His efforts with 3D printed ceramics would work much better if he’d fire a glaze onto them to eliminate the porosity.
Give him a break, he can afford to buy metal or bow ties, and I think he made the right choice.
I don’t think you’ve watched any of his content other than this video. Integza purchased ceramic epoxy resin and fired the nozzles. These should have survived long enough for his tests, but they MELTED. That means the temperatures were reaching at least 6000 degrees.
The guy is amazing, but is still learning. Give him time, he’ll get there.
You could make everything out of metal, yes. But then you see pretty much nothing what reacts inside.
50% hydrogen peroxide is an… unpleasant… material to work with.
This was used in rocket dragsters and the Bell Rocket Belt, and IIRC Evel Kneivel’s ill fated launch? Or was that super-heated water/steam? Nice video.
Kinda. They used a silver mesh as the catalyst to avoid the nasty mess. Potassium permanganate stains everything.
The Skycycle X-2 used steam. https://www.tnairmuseum.com/virtual_exhibits/evel-knievels-skycycle-x-2/
Seriously where do people get these high concentrations of hydrogen peroxide? I thought it was near impossible for individuals other than chemists since terrorists tried to use it years ago.
I think he’s in Portugal. There are a lot, a really big lot, of things you can do all over the world that you can’t in the US because de big brother gives the excuse terrorists will kill you if it is easily available.
Let’s be honest though, with high test peroxide you are more likely to kill yourself plus any family or friends.
I’m friends with Ky Michaelson and Jack McClure and some of the other ex rocket racers. 95% peroxide is very difficult to get and the stabilizers used now are problematic. One friend had a liner breakdown in a storage container and it hard enough to get the ATF’s attention.
80-85% peroxide was used as a catalyst for C-Stoff in the Me-163 rocket fighter employed by Nazi Germany in WW-2. A large percentage either exploded while fueling or when the pilot attempted to take off. Dangerous Stoff (no pun intended)
Fair enough. But they still give the same “bad guys will do bad things” bs excuse.
Yeah. Then there’s commonly available things in th US that cause panic attacks in European countries.
A common tree stump remover in the US is potassium nitrate. You can buy it in 1 pound or 4 pound jugs in pretty much any store that sells stuff for yard work.
You can’t buy that in Germany because of its potential use in explosives.
When my son and I were in the US visiting my family, he made a picture of a shelf full of jugs of potassium nitrate stump remover in a store to show his friends. It was (from a German point of view) surreal to see this stuff in a store where any one could buy (or steal) large amounts of it.
That’s because Germany had a real rash of domestic terrorism from the 70’s through 90’s. Groups like 2 June, Bader-Meinhoff, NSU, RAZ… every couple years some anarchist or far left loony stuck a pipe bomb under someone’s car.
Like there’s a shortage of domestic terrorism in the USA:
https://en.wikipedia.org/wiki/Domestic_terrorism_in_the_United_States
Plenty of bombings in among the shootings.
>with potassium permanganate as a catalyst.
Might want to relearn basic chemistry. Potassium permanganate is used as an oxidizer in this reaction. It is chemically changed, so by definition not a catalyst.
Elephant’s toothpaste uses use or KI as a catalyst to promote the peroxide decomposition, this is a different but similar reaction and they slightly conflated the two, but no need to be snide about the pedantry.
Retired chem prof here. The permanganate ion is indeed a catalyst for peroxide decomposition. The fact that it also undergoes a separate redox reaction to form a different product does not negate its catalytic activity.
Manganese in (almost?) any oxidation state will catalyze peroxide decomposition. If it can be obtained, manganese(II) acetate works well and is rather less messy; it is a pale pink color rather than the deep purple of permanganate.
Fun fact: the the turbopump on the V2 was powered by hydrogen peroxide and a potassium permaganate catalyst. If memory serves, that pump produced 600 hp.
Soyuz launch vehicles (at least those that use RD-107 derivatives) still do exactly that.
“creating a jet of water and oxygen” Can you direct it into another chamber with something flammable to burn and make even more thrust?
Yes, it is possible to add additional fuel to already reacting peroxide and increase the energy. I’m not a chemistry guy, but I would guess that you need the oxygen and injected fuel to be combustible enough to overcome the water vapor.
Tomatoes are disgusting!