Acoustic Horn Design – The Easy Way (Ath4)

Can't wait to learn how it fits.

Regarding the finish, I think about filling an epoxy coating (the XTC-3D perhaps) with a metal powder. I don't want to spend hours making the surface perfect, which it wouldn't be anyway, so I thought to make it intentionally looking old and battered instead 🙂
 
Suddenly it's funny how is the ST260 actually small - ST260 vs CE360 petals.
And I also already know the tolerance needed - the groove on the petal is 0.3 - 0.4 mm too narrow in my case. Shouldn't be problem to fix this.
 

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YES! 🙂

- No sanding yet, these are raw pieces as they left the printer, no glue yet.
I only wish the inner surface of the base was better but it seems I can't figure out how to do that in this case.
 

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YES! 🙂

- No sanding yet, these are raw pieces as they left the printer, no glue yet.
I only wish the inner surface of the base was better but it seems I can't figure out how to do that in this case.
Rough after the first 1/2" of throat is good.
I've found I like fine sand in the paint roughening the surface.

Fun seeing you do this.
I've turned several pairs of Tractrix 550Hz horns on my lathe, and adapted an end sander to allow me to turn the larger diameter Le Clèac'h 550Hz horns.

You could experiment with small ridges ala Cessaro horns and see what sounds best.

What will the resonace / stability be like? Use bitument to dampen?

I've found the softer the wood the better the sound for higher frequency applications.
I don't know how printed plastic compares.
 
What will the resonace / stability be like? Use bitument to dampen

If I am able to print one of these I'm going to place the horn on it’s mouth and fill the trough with self-leveling polyurethane via a caulking gun. More expensive but it comes in black, white and grey and I like the clean look.
 
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As I have it now, it would fit into 170 x 170 x 110 mm (x,y,z) build volume (e.g. Prusa MINI+ is fine).

Continuing on the ST260 (no filler, no sanding, no glue yet) -
(Wonder what angle ajustment will require the last petal. So far it looks pretty accurate.)
 

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