I figured a simple 120VAC to 12VAC transformer would do the trick. I need some stuff from Jameco, so that'll be in the cart.

Here are some teardown pics of my horn:
https://www.flickr.com/photos/32548582@ ... 286280377/

I'd rather get the math right and only have to do one or two prints. I have the impression you meant to edit the 3D model so it'll print pre-balanced. You could do that, but it would be too much money, time, and effort. The thing is, it doesn't matter how much math you do, the plastic doesn't have ...

That's the easy part of the problem. Positioning N slots is easy; just do 360 / N. Now consider two sets of slots stacked. If you have one slot right on top of another, that side might be lighter than the other side and therefore the chopper will be unbalanced. The problem I want to solve is how th...

I didn't think of 3D printing. The hackerspace I'm thinking of has a 3D printer capable of making objects in bronze, among other metals. For this, I think it would be best to make the chopper, stator, and lid. The rest of the chopper group might be easily done with common pipe. Eric's effort seems ...

I didn't think of 3D printing. The hackerspace I'm thinking of has a 3D printer capable of making objects in bronze, among other metals. For this, I think it would be best to make the chopper, stator, and lid. The rest of the chopper group might be easily done with common pipe. Eric's effort seems t...

http://www.civildefensemuseum.com/sirens/miniT/2chopmothouse.jpg This is the first unstable rough version of the single tone chopper and stator I made for it. To say this "shouldn't be too tough" isn't based in reality at all. If you don't have any real background it operating a lathe and...

I guess what I'm trying to say is that I can conceptualize the process fairly easily. I'm not after a completely faithful scale model, but something approximately the same shape and proportions. Like your approach, things like exact size will be dependent on the size the chopper group ends up being.

Guys, guys. Stop. There's been enough flaming, bashing, and generalized drama lately to choke a horse...let's not add to it. Now as for the question of whether Frotz is referring to 5s vs 7s or As vs Ls...I'm not a mind reader, so I'll let Frotz answer that. :wink: Yeah, I misread the topic. I was ...

Is the 41" figure for just the chopper housing? How about its diameter?