The Siren Board

I have come up with a way to reshape my dented horns using various things around the shop that might not usually be considered tools..such as round logs, scrap lumber, along with fender hammers and dollies. Does anyone have any pointers on repairing projector horns?

Your dented horns would fall under the same category as automotive type sheet metal repair.Barkless round logs of similar size and circumference would help you get back the initial roundness, to do the finer crease repair I would invest in a couple of flat autobody style hammers and pan dollys to help straighten out any slight crease variations.the Pan dolly is like small hand held anvil. If you have a Harbor freight tools nearby you that have a reasonably priced autobody tool set with everything you'ld need.If not it can be ordered online from their site.Or if you have a local auto pain & body supply near you, those tools can be found there. Hope this helps...

You might want to try an English wheel, Harbor Freight sells those as well.

If the things are REALLY bent up badly you will run into all kinds of weird things when trying to bend them back into shape.
Sheet metal stretches pretty bad when it's bent and when you try to bend it back you will see what happens as soon as you start working.
The metal will start doing all kinds of weird things. I learned this within the first minute when I tried to straighten the rotator box top on the first
Thunderbolt I rebuilt.
Also if you hammer it too much you will stretch it by mashing out. Just don't get too wild with the hammering and take your time.
Since they are round cone shapes maybe you will be able to get them back close into shape but don't expect to be able to make them look new again if they
are badly bent up.

English wheel? Enlighten me, pls

They can be used to fix the lips on the horns, and to smooth out and also curve sheet metal. The best thing to do would be to watch a YouTube video of one, you'll see what I mean.

1000chb385 wrote:English wheel? Enlighten me, pls

http://lmgtfy.com/?q=english+wheel

Cool... I looked them up... Would be quite handy. Im new to sheetmetal repair work.

Gentlemen: my post was intended to say i finding objects lying around to assist in my endeavors... This is different than repairing automotive sheet metal in that both sides of the repaired metal horn are visible, and that body fillers would be inappropriate. This is a whole new ballgame. And... An auto body repair guru friend pointed out today that many of these dents probably were caused by hail damage... Doh! Its a tornado siren..he says...and YOU don't know what an English Wheel does? ."what is everybody dumb?"-- referring to a Curly Howard quote-- directed at me, the jester....

My next question: how did Federal manufacture these projector cones?

They made them like you would make a foot of an organ pipe. Only they would use a roller not an mandrel. Here is a video for a reference. https://www.youtube.com/watch?v=boS0CP1-u1c