And Now For Something REALLY BIG

[JRKO]

Ok I have supplies:

1x small sheet of 5mm foam board - will test if kerfing makes it useable
1x A1 sheet of mount board - might make the interior with this or maybe a 3D template
2x A1 sheets of 300gsm cartridge paper - cheap & chearful
1x A2 sheet of 350gsm watercolour paper - nice & heavy
PVA & a nice scalpel

All I need now is the exponential curve to start my trial run

[Pano]

I used a lot of layers on my small horns and they were very solid. Not really sure how many you'd need here, as the metal horn cells are much thinner than single metal horns. Strength in numbers, I suppose. FWIW, I held the walls together with masking tape, then glued paper strips on top of those. Used wallpaper paste as I didn't want any PVC on my horns. Probably made no difference at all, it's just silly idea to keep them "all natural". It did work, they seemed to have no sound of their own.

You'll be building at least 16-20 cells, so why not experiment with a few to see how it goes? Materials are cheap. If you practice some and throw away the fist few, then you'll be quite good at it when you build for real.

The tricky part is getting the sides to line up once they start to curve in 3D space. My horns were 8 or 9 sided (IIRC) and shorter than 15" - thus a real struggle to join. 4 sides and longer may not be so bad. You'll soon find out!

[Pano]

Originally Posted by JRKO

All I need now is the exponential curve to start my trial run

Do you want the curve off my 1005? Or will you be doing a different size?

[JRKO]

1005 = 10 cells in 2 rows of 5?

6.25" is 15.875 cm so that would be 79.3...cm wide. According to this (http://www.voiceofthetheatre.com/images/multicell.3.jpg) width is 30"/5 = cells should be 6"

I typed that chart up as what A B C relates to is on the other page

--803B D26.5-----W32-----H16.25
--804B D23.5-----W32-----H16.25
--805B D17.5-----W24.5---H13
1003B D25.5------W38-----H16.125
1004B D20.5------W38.5---H16.25
1005B D17.25-----W30-----H13
1504B D21--------W38.75--H24
1505B D16.75-----W30.5---H18.5
1803B D23.5------W44------H24
1804B D23.5------W44------H24

1005B looks about the smallest - I hope I can make pretty with paper

I think I'll cover the childlike mess underneath with a fresh sheet of glam paper to finish

[LFM]

Hello Pano. I would really like to know the curve of your 1005 horns . I wrote the other day that I wanted to clone a 1505 horn using wood veneer. This was a mistake and its the 1005 I want to clone. I was really hoping that you would offer to provide the measurements from your horns. I didn't want to ask. I think you are being very generous here. We all know how critical it will be to have the correct throat dimension. Would you consider whipping up a something similar to a auto bore snap gauge to measure this. I would be happy to make one up and send it to you if that would be better.

[JRKO]

Originally Posted by Pano

Do you want the curve off my 1005? Or will you be doing a different size?

Yet please Pano. I'll start with a few practice runs but it pays to have an actual product to copy. Might look at more cells for the final job as per you preference but I shouldn't get ahead of myself. Need to perfect the new art of 紙ラッパ (roughly translated as paper bugle/horn/trumpet). As far as the measurement I get from the calcs go it looks like a width every cm along the cell. Is that right?

[Pano]

Originally Posted by JRKO

1005 = 10 cells in 2 rows of 5?

Correct!

6.25" is 15.875 cm so that would be 79.3...cm wide. According to this (http://www.voiceofthetheatre.com/images/multicell.3.jpg) width is 30"/5 = cells should be 6" [/QUOTE]
The front is curved. Add an extra 1/4" to each cell and you'll see the curve. From mounting tab to tab it's 28". But along the curved face between the 2 rows it's closer to 34".

[JRKO]

Of course I remembered the curve hhuh hhummm

It'll be fun getting internal measurements. As noted above thanks for being so generous Pano

[Pano]

You're welcome! Here is another pic.

[JRKO]

Super clean horns there Pano.

Wouldn't the lip at the mouth of those cells do something to smooth the projection of sound? It looks like its hiding the joint between cells maybe?