DIY Radial Horn

I have three options:

Make it out of beautiful hardwood
Make it out of beautiful layered ply
Make it out of (cough cough) beautiful layered MDF

What you say?

I'd go for a nice layered ply.

Can't wait to see the result... smiley20

...

I had some quality time with the tools. The mill can only do 20cm length rdials at a push from solid wood (I tried, it makes a horrible noise when pushed further...) I'm thinking a little bigger for the 1.4, I'd like at least 28-30 for a lower xover frequency. Or should I recalculate for 1"ers and keep the horn small?

So I've come up with a plan. Make it out of many small cheese-like slices, and then use the rotary table to smooth things over somewhat (or a belt sander if it refuses). This is quite different to the construction of normal biradial horns I've seen around (making it layer cake style would mean more work for the very anemic mill). This way, it's also easier to build it as a multicell, 811 style (this iof course would be designed differently)

On the plus side, I got to make some new prototypes for turntable stands out of brass. They are spikes that fit into recessions filled with silicon squidgy sealant. Effective. I should put up pictures of those very soon.

Just a small point about material for the horn. From a purist point of view, I would use ply. My thoughts relate, as usual, to resonance. I learnt many years ago that making any sound equipment out of solid wood was not a good idea. This is because of energy transference down the grain. Although there is grain in the veneers of multi-lam ply, the resonance is at a minimum, because of the separation. The horn should be neutral and not add anything to the original signal. A non resonant horn is the best one to have.
The ply horns I have made in the past have always been coated with resin on the inside and laid up with glass on the outside. The wooden surface can soak up hf, so producing a hard surface on the inside is important.

I have started ripping into a piece of ply and have cut it up into bits that will be glued into a swiss roll.

I'll resolve to put up pictures of everything at the end or sometime soon.

I regret to say that this project will be on hiatus again, unfortunately half-way through construction; due to an obstructive bodily injury on my part preventing me from operating a bandsaw. Hopefully I will be able to shape the rest of the 32 bits of wood and glue them together in a couple of months.

Milling took too long, so I chopped it up into the slices on the table saw and started cutting the curve manually on the bandsaw.

I fell off a bicycle badly a few weeks ago, this project has sat shelved until I can operate a bandsaw safely again.

It always takes waaaaaaaay longer than you thought it would, doesn't it.

Ouch! Get well..

Is this bicycle thing why you have dissapeared!?

I was searching your posts to find out why!!

Get well soon

Jake

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Not dead yet.

As of today, they've been glued into the 90 degree fans and are being sanded while I find the original numbers (It's not going to be fun reverse engineering the throat size from these bits of wood).

I also now have access to a large CNC, but that's something else entirely.