THE WORLDS SIMPLIST JET ENGINE WITHOUT ALL THE CONE ROLLING ETC
You will know by now that i kinda like pulse jets so trying to make one using this method sprung into my mind just after i saw the process for the first time. The jet you end up with will look a little strange as you can not go from say a 3" diameter to an 8" diameter as quick as the design of the jet would want you to because it just kinks and forever tears on the corners. below is the trail and error attempts at getting the combustion chamber to form and of corse work as a jet.
As you can see i made a lot of scrap metal haha. The 3rd one in in the line formed the cleanest but when adde to the rest of the jet it would not run as needed to be fatter if such a shallow taper so the result after many sheets were destroyed was this as a flat pattern
If you haven't watched the video you may wonder why its not a U shape well this comes down to the sides contracting and outside measurements reducing so once formed it pulls itself into a U which is quiet cool to watch. I'll try n put some dimensions on incase you want to replicate this as is is the quickest way to make a pulse jet.