Mounting horns below radar dome

[OrangeCrush]

I want to mount an Ongaro Deluxe Electric Dual Trumpet Horn on the bottom of my radar swivel mount. I already did this before with the Ongaro Dual Mini horn and it worked fine, but the Mini horns died and I want a slight upgrade (so I no longer sound like a taxi cab out there on the water).

The trumpet horns are 18" long and the radar dome is 18" in diameter. The swivel mount has a plate on the bottom with large holes that I can attach hardware to. I want to angle the horns downwards at an approximately 45 degree angle. I'm thinking I'll make a bracket to hold the horns at this angle.

I think the easiest thing would be to get a long piece of 1" stainless steel strapping and bend it in a vice to make an isoscelese right triangle, and screw the horn onto the hypotenuse.

Has anyone done something similar? Any alternative solutions? And if this is my best bet, can anyone tell me what gauge stainless would be ideal for this, so it can bend it easily but it has enough strength to retain its shape?

Thanks!

[tkeithlu]

I'm guessing that the horns don't weigh much. I'd use about 1/8" stainless. Do you have access to serious heat, such as a mapp torch or oxy-acetylene? That would make it easy.

Cosider the possibility of cloth covers to keep wasps out.

My experience with electric horns is not all that positive. They all seem to die pretty soon in a salt environment, and I discover that when I'm about to run over a drunk tourist in a pontoon boat.. I've actually moved to canned gas horns, with a wire down into the wheelhouse that lowers a plate on the botton on the horn. Much more reliable.

[OrangeCrush]

I share your disappointment with electric horns. I do keep a regular air horn handy as a backup, but I also need a wired horn for use with my FogMate automatic controller. I sail in the fog in Maine a lot and sometimes find myself sailing through a group of lobster boats, and I want them to know where I am. (Although my crew hate it)

Yeah the horn is only about 2 pounds, but I think the bracket should be strong enough to lift the weight of the radar dome on its swivel, in case a line or the leech of my jib gets momentarily snagged on one of the trumpets.

1/8" is thicker than I was thinking but maybe a good call. Yeah I have a blow torch and MAPP gas if it will help me make the bend in the stainless.

[toddster8]

I’ve got the hailer horn for my VHF mounted under the radome. It has its own quadrant-shaped bracket to control the angle. I broke it during the last haul out and made a new one from the bracket of a caster wheel from Home Depot. It’s looking a little rusty - might make a new one from heat-formed ABS, which is what the original was. (Because I wanted to do a lot of work on the mast, I thought it was a good idea to shlep it inside the greenhouse for the winter. But fully rigged, it proved impossible to get it back out without breaking something.)

It covers the horn function and the automatic fog signals. But you have to hunt through the menu system of the radio to get to point where you can sound the horn, by which time whatever was going to happen… has. So close to being useful, but not close enough.

[sailon46]

Blow on a Conch shell honkie

[seabreez]

Originally Posted by sailon46

Blow on a Conch shell honkie

I want a conch shell. Been trying to get one. Where can I get one?

[Orion Jim]

Originally Posted by seabreez

I want a conch shell. Been trying to get one. Where can I get one?

Check any of the search engines and you will find them at reasonable to exorbitant prices.

[skipgundlach]

Originally Posted by seabreez

I want a conch shell. Been trying to get one. Where can I get one?

Nearly anywhere in the Bahamas will have one available.

Or make your own; very simple if you own a hacksaw, even better a cutoff wheel in a 4.5" angle grinder.

However, the key to both comfort and performance is after you've cut the requisite 3 rings off:

If you have or can buy one, use a ball grinder (1" will work well) chucked into your favorite drill motor, and use it on the opening you just created. That will accomplish one critical and one comfort item:

The ball makes for a chamfered lip (where your embouchure, commonly known as your lips, hits). It will be much more comfortable to play your sunset salute that way.

If you don't have a ball grinder, chip out the shell inside the opening you made. If your lips touch that, it will impeded their vibration and you will either get no sound, or horrible sound. You don't have to go very far (a ball grinder will penetrate only about 1/4" or so), but you have to relieve that shell which will foul your mouthpiece.

If you happen to have brass experience, and have a current or dormant embouchure, you can do as I did and adapt a plumbing fitting, epoxied into a somewhat larger hole, to be a receiver for either a french horn (much deeper and more mellow sound) or trumpet (much higher and brighter sound) mouthpiece.

My "conch" horn isn't at all, but instead the picture you see when you look it up in the dictionary; that's much more mellow than a conch, and I used a screamer (very shallow cup) mouthpiece. I can get several octaves, and, if you're a brass player, you know the intervals get much closer together as you go higher.

Which enables me to play the William Tell Overture (Lone Ranger theme) at the end of my variously-tuned salute-to-the-sun!

[StoneCrab]

1/8" is overkill if it is stainless.
Stainless is extremely stiff for its weight. I'd use a thin gauge for lightness and add flanges to the straight sections. The flanges make the cross-section a "u" shape by turning the edges up. These flanges will make the assembly incredibly strong. These flanges can be made with a box and pan brake or by hand tapping along a line, folding the metal over the edge of a thicker piece of metal.

If you know any body shop guys who like metal shaping and work on old cars, they probably have a bead roller capable of forming this flange or even a rolled over flange like you see on the top edge of a metal bucket or the wheel well of a 1930's car.

It will be a fraction of the weight and probably stronger. So stronger, cheaper, lighter....that is the way I'd go. Putting bar stock high on a boat doesn't sound like a good idea if only in principle.

Even if you build something out of aluminum, roll or press some shape into the cross section for strength. For an example look at the ribs in an aluminum canoe. They have a round rib pressed into them. Incredibly strong and light. 16 guage is readily available.

[KP44]

Originally Posted by OrangeCrush

Has anyone done something similar? Any alternative solutions?

I used a chunk of uv-resistant nylon. I cut it to fit between the braces of the radar mount where it was easy to attach it. My hailer horn attached to the plastic. A few layers of starboard would do the same as a solid block.
My hailer horn does fog signals from my VHF, can be used for listening or hailing, and can deliver low-pitched "horn" signals.