Yeah those tabs are nice. Gotta make it easier to get the thing together. I did have trouble keeping the edges of mine together while gluing.
Isn’t it amazing how the simplest of techniques can at a stroke, make the seemingly impossible, effortlessly doable?
ToSThe two part single cell mold is printed I had to redesign the locks a bit, but the final STL is available on request. I do not know if I am brave enough to try to build 30 cells
3D printing the full horn is out of question until I have my own 3D printer to do test prints for the locking arrangements.
I had to redesign the locks a bit, but the final STL is available on request. I do not know if I am brave enough to try to build 30 cells 3D printing the full horn is out of question until I have my own 3D printer to do test prints for the locking arrangements.
Attachments
The two part single cell mold is printed
My my, that is very impressive, I see what you mean by having a built in locking arrangement.
I am rather new to the concept of 3D printing, and cannot help wondering if it would be possible to print using wood-flour suspended in a solution of say, corn starch - like how a wasps nest is built. I am sure it is doable
ToS
The two part single cell mold is printed
3D printing the full horn is out of question until I have my own 3D printer to do test prints for the locking arrangements.
Very nice. How long did that take to print.
What about using the print as a mold and fiberglass to create the actuals.
pelanj,
I too have worked with fibreglass and epoxy. Even though the end result was good, I found the process very stressful. Frankly, it is probably a job for a professional fabrication workshop and if done properly, would not be cheap.
Having worked extensively with paper and glue, I can assure you that with the right approach, paper mâché can be a very precise and accurate medium - a delight, in fact.
My approach would be to make a master set of ‘mirrored’ templates, and cut the walls of the cells from them. A cell can be held together with small pieces of masking tape, and then removed one piece at a time as the paper tape is applied to the walls of the cell. Upon drying, the paper tape will shrink and by doing so will increase the overall strength of the structure. When done well, paper mâché is immensely strong. At one time the Japanese used it to make lightweight armour.
I could talk about paper mâché construction all day long, and if you really are intent upon making a multicell horn out of paper, I say you will succeed.
ToS
I believe in paper mache, but I am not so sure about my patience
Yep, if done well, two layers will be enough. Some advice:- paper, card stock, and starch based glue are deceptively simple materials with complex properties that only become apparent during the rigours of construction. So, keep a journal and take photographs. Also, stick with starch, and not be tempted with PVA, cyanoacrylate, or epoxy as they will cause problems later on. Good luck! ToS
Yes, I agree, but the anti-mould agent is toxic, and if it triggers dermatitis .....
My workaround is to make a fresh batch of starch based glue every 3 days or so while I am working. If I need to keep it for longer, I decant the hot batch straight out the pan into a pre-sterilised Kilner jar, seal it, and allow to cool to room temperature - then pop it in the fridge. Then it will keep for several weeks.
My workaround is to make a fresh batch of starch based glue every 3 days or so while I am working. If I need to keep it for longer, I decant the hot batch straight out the pan into a pre-sterilised Kilner jar, seal it, and allow to cool to room temperature - then pop it in the fridge. Then it will keep for several weeks.
You can use wheat flour, corn flour. I use rice flour. The Japanese call it Nori. Doesn’t really matter all that much what sort of vegetative source of starch is used, so long as it is de-husked and finely ground.
Starch glue recipe:- one part of (chosen) flour plus four parts of cold water. Gently stir in the flour till smooth - not lumpy. Very gently bring to the boil and keep on stirring until it suddenly starts to coagulate. Keep on stirring until clear-ish. Keep on stirring. If in doubt, stir some more. Should be nice and thick and gloppy. Decant into sterilised Kilner jar and seal. Best to leave in the dark and keep cool for a couple of days to firm up. This is your concentrated stock - dilute as per application. When the jar is opened, the stock will last about three days before it gets kinda funky. Don't be precious about yah glue, as it is cheap and can be made up very quickly.
ToS
Well, if yah gonna fill the spaces with tar, or sand, or sawdust - or maybe a mixture of all three, then Masonite is good to go!
I’ve been thinking about building a multicellular horn myself. There is something really appealing about compounding a simple structure into something sophisticated. I reckon it can be done really accurately, too.
I have a NOS Paradigm single point stereo ceiling speaker that I would like to incorporate into a multi cell....... maybe 15 x 9 cells, as in 5ft wide by 3ft high that I can actually get through a doorway
ToS
I’ve been thinking about building a multicellular horn myself. There is something really appealing about compounding a simple structure into something sophisticated. I reckon it can be done really accurately, too.
I have a NOS Paradigm single point stereo ceiling speaker that I would like to incorporate into a multi cell....... maybe 15 x 9 cells, as in 5ft wide by 3ft high that I can actually get through a doorway
ToS
Wow, you have big doors in Scotland!
I wonder just how much bandwidth a multi-cell can cover? The cells on the Altec 300Hz horns are 8x8". Don't think you'd want to go much larger per cell. And how deep would you go? 6 feet, 2 meters, more?
FWIW there is a pair of 24 cell horns on eBay right now. The cells there are 6" on a side, and they look conical to me.
vintage Western Electric 24 cell Tar Filled horn for westrex-altec-rca very rare | eBay
I wonder just how much bandwidth a multi-cell can cover? The cells on the Altec 300Hz horns are 8x8". Don't think you'd want to go much larger per cell. And how deep would you go? 6 feet, 2 meters, more?
FWIW there is a pair of 24 cell horns on eBay right now. The cells there are 6" on a side, and they look conical to me.
vintage Western Electric 24 cell Tar Filled horn for westrex-altec-rca very rare | eBay
I am wondering about using expanding foam and hoping to reap the damping benefits without the weight.
What do you guys think?
Would be great if it works, I think there are different densities of expanding foam, depending on the intended application.
I'm currently building some multicell horns from ~5mm plywood. I'm planning on trying some cld material on the outside of the horn cell walls, to ideally alleviate the need to fill with tar/epoxy/unicorn farts, etc.
CLD:
Amazon.com: Noico 80 mil 18 sqft car Sound deadening mat, Butyl Automotive Sound Deadener, Audio Noise Insulation and dampening: Automotive
Cheers,
Gable