www.pulse-jets.com

Well I’m officially addicted. Based on PryoJoe’s design I built my first pulse jet. Built it all out of exhaust tubing. Using a 2” ‘caliber’. Took about two hours of fabrication and an hour it tying to get it to run.
You can see a video here https://m.youtube.com/watch?v=rteNAXN3YjU

So I am looking for my next one to build. I was thinking of getting a slip roller and making the bottom of pyro joe’s plans to the same dimensions as my current one. Will this one be noticeably better, louder and awsomer or should I scale it up?

Excellent! Nice work.

As far as a new jet to build, scaling is a bit risky (although scaling *up* is usually more forgiving).

A Lockwood is a fairly forgiving design, and produces useful thrust, for something smaller there's the various FWE engines from Larry. There's loads of plans in the pinned topic at the top of this forum. And yeah, you'll need a slip roller for most of them.

Oh yeah I was definitely thinking of going bigger! Has anyone had any experience with the cheaper slip rollers like what you can get off Amazon? Will 20-22 ga steel be thick enough?

Not sure about amazon slip rolls, or what they cost. I don't trust cheap shit bought across the 'net, though. I made my own rolls, from scrap, cost next to nothing. Here's an idea - https://www.youtube.com/watch?v=m7eNLv6BR4Y

As far as thickness goes, it's easier to bend thinner material, but it will burn / corrode through quite fast (stainless will help with this), and on bigger engines collapse is an issue. Plus thin stuff is a bugger to weld.

Use 1mm stainless steel for engines that last a good while. You can also still weld 1mm steel pretty well. A slip roll is useful but by no means necessary! You can get really good results with a piece of round and later square pipe clamped in a good vice and a hammer. That's how I built most of my engines, including the bigger ones. When you get to Lockwood-sized engines, I recommend making the cone sections in 2 or 3 pieces.