Hey Cal, the rig is definitely more than is necessary. I like it for a few reasons.
1. I loosened up several paper strips when using the table leg. This allows for no cross-friction.
2. Keeping the bottom edge of the strips flush to the board insures straight and better aligned vertical segments in the curve.
3. I like the flexibility of using various radius tubes. Almost like working with clay on a form.
My fourth concept dealt with insuring uniformity with a mark, but I prefer the ideas in the last few post much better. That's the magic of the forum - useful ideas start sprouting up all over the place.
The pic is "tools of the trade" literally.
Trying Gorilla on this one.
1. I loosened up several paper strips when using the table leg. This allows for no cross-friction.
2. Keeping the bottom edge of the strips flush to the board insures straight and better aligned vertical segments in the curve.
3. I like the flexibility of using various radius tubes. Almost like working with clay on a form.
My fourth concept dealt with insuring uniformity with a mark, but I prefer the ideas in the last few post much better. That's the magic of the forum - useful ideas start sprouting up all over the place.
The pic is "tools of the trade" literally.
Trying Gorilla on this one.
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Cal,
I plan on another Mini Cornucopya but with maple or birch plywood facers - kind of like Bob's. I may grow to 24 in size to make full use of plywood sheets which come in 24 x 48 inches. Also, may boost the lower bass notes rather than just mid bass. I am thinking of maybe modding with 2 equal path horns that have just a short divider near the ends to split into 4 horns but divider is so short that it is more of a 'brace'. This will not have the split paths. Although with my measurement of pink noise emanating from various mouths today, I see that it really does work to have mid bass on 2 horns, and lower bass on other two horns. Maybe this is the magic that makes it work, despite what the modelers say why it is not a good idea. Still thinking...
I plan on another Mini Cornucopya but with maple or birch plywood facers - kind of like Bob's. I may grow to 24 in size to make full use of plywood sheets which come in 24 x 48 inches. Also, may boost the lower bass notes rather than just mid bass. I am thinking of maybe modding with 2 equal path horns that have just a short divider near the ends to split into 4 horns but divider is so short that it is more of a 'brace'. This will not have the split paths. Although with my measurement of pink noise emanating from various mouths today, I see that it really does work to have mid bass on 2 horns, and lower bass on other two horns. Maybe this is the magic that makes it work, despite what the modelers say why it is not a good idea. Still thinking...
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Hey Cal, the rig is definitely more than is necessary. I like it for a few reasons.
1. I loosened up several paper strips when using the table leg. This allows for no cross-friction.
2. Keeping the bottom edge of the strips flush to the board insures straight and better aligned vertical segments in the curve.
3. I like the flexibility of using various radius tubes. Almost like working with clay on a form.
My fourth concept dealt with insuring uniformity with a mark, but I prefer the ideas in the last few post much better. That's the magic of the forum - useful ideas start sprouting up all over the place.
The pic is "tools of the trade" literally.
Trying Gorilla on this one.
LoL
a Sewing machine on top of the horn as a weight. Pretty funny. Great progress Bob. You are so close to making first sound. Let us know how the Gorilla glue works for the face.
Your clamps look awfully familiar.The pic is "tools of the trade" literally.
I am really looking forward to your impression of them.Ya, that's another thing about these. I am forever scheming up something all because of the success of the first pair.
Here are some photos of the Gorilla glue action. It is actually a tad thinner than wood glue but holds it's form well. Some running can be seen, but that happened only after adding the weights.
The foaming shown is after about an hour. It might be a good idea to flip the build placing the glue on the bottom. That same packaging tape can be used to hold the cover in place while flipping. Looks like it will do a great job of "fill and seal". Will require some trimming on the outsides.
The foaming shown is after about an hour. It might be a good idea to flip the build placing the glue on the bottom. That same packaging tape can be used to hold the cover in place while flipping. Looks like it will do a great job of "fill and seal". Will require some trimming on the outsides.
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Bob,
Cochleus says the G glue dries in 20 minutes. You should be ok in a couple hours I would guess?
That's sweet that you have drivers in hand. Those things come in the cheapest packaging possible, you would not imagine something that sounds this good comes in such a skimpy piece of cardboard. Not even a full box. We are all waiting with great anticipation for your first sound.
Cochleus says the G glue dries in 20 minutes. You should be ok in a couple hours I would guess?
That's sweet that you have drivers in hand. Those things come in the cheapest packaging possible, you would not imagine something that sounds this good comes in such a skimpy piece of cardboard. Not even a full box. We are all waiting with great anticipation for your first sound.
O.K , I'll check the set and if the tackiness is gone I'll start gluing #2. Maybe sounds still tonight but no promises. I want to use new clean pillow stuffing so a trip to Jo-Ann Fabrics is last on the list. I have some of the PE stuffing but it's just a handful. And no, before you ask - I'm not going to tear apart the Sunflowers to get at the stuffing.
Maybe the Dollar Store nearby (where I bought the foam board) might have another great value.
Maybe the Dollar Store nearby (where I bought the foam board) might have another great value.
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That does bring up a valid question. Whether downy fluff or heavier cotton matting type? I just bought a jumbo Dacron pillow at the Dollar Store for $5.
Unbelievably, my large glue gun blew up as I was leaving for the store. It fell over, was up side down and the glue seeped into the wires. No fire but I did have to change my shorts (pun intended) Proud owner of a new gun.
Unbelievably, my large glue gun blew up as I was leaving for the store. It fell over, was up side down and the glue seeped into the wires. No fire but I did have to change my shorts (pun intended)
Proud owner of a new gun.
Yes, great way to test the stuffing. Stick a sock in it has a different meaning to us speakerholics.
I use rockwool for my stuffing. I gave up on the polyester and fiberglass stuff. I hear lambs wool felting works well.
Glad it wasn't worse. I usually walk away from the gun while it is heating up so I'll have to be more careful.
Hey Cal, actually I have been hiding under my bed for the past few hours waiting for the Mayan apocalypse to start. Checked all the TV stations so my courage is renewed.
So, both cabinets are glued with leads in place. Just have to cut holes, stuff the driver chamber, mount drivers and hook them up.
BTW, do you suggest tacking all the stuffing with a few drops of hot glue. Don't know how much actual air movement there is.
Should be about an hour.
So, both cabinets are glued with leads in place. Just have to cut holes, stuff the driver chamber, mount drivers and hook them up.
BTW, do you suggest tacking all the stuffing with a few drops of hot glue. Don't know how much actual air movement there is.
Should be about an hour.
That is not the place to spend your last few hours.
I just made a cup out of the rockwool and use friction to fit it.
If your estimates are anything like mine, we'll see you in a couple.Should be about an hour.
So, both cabinets are glued with leads in place. Just have to cut holes, stuff the driver chamber, mount drivers and hook them up.
Should be about an hour.
You did not cut holes in plywood before gluing? I do that on the foam core facers but that is easy with an x-acto after the fact. The friction and pressure from stuffing the stuffing holds it in place just fine. Maybe if you had used loosely stuffed stuffing in the channels, the glue would be a good idea. But too late for that now. Ok, we are waiting and the clock is ticking...
Bipole Cornucopya on Stands?
I just had a crazy idea for a cornu bipole stand mounted setup that is very "OB-like". Make a double layer spiral on a central board (hot glue in place). This board has a hole in it like original cornu. I would make the spirals left and ride handed on opposite sides. On the outside faces, have cutouts on front and back and mount two drivers wired in parallel for a bipole setup. This is no longer a wall mounted speaker but needs some cool looking legs to get it up to ear height. Kind of open baffle like but without a huge open baffle, just the cornu baffle, at 24, 28, 30 inches whatever you prefer. If you wanted to go nuts, make a really big cornu baffle to be about size as typical open baffles and get some monster bass with an 8 inch full range. I would do this with something like the Wild Burro Betsy at $100/pair. If you wanted to spend more on an 8 inch FR, maybe the Tang Band W8-1772. If you really want to cheap it out at 8 inches, do the Visaton 3020 BG20 (Sd is 214 cm2). Another slightly smaller option is to do a 6.5 inch full ranger. Has anyone tried the Visaton 3017 BG17 (93 dB efficiency for $16 ea)? The soundstage would be very big, and the bass would be killer. It would certainly be unique. What do you guys think?
I just had a crazy idea for a cornu bipole stand mounted setup that is very "OB-like". Make a double layer spiral on a central board (hot glue in place). This board has a hole in it like original cornu. I would make the spirals left and ride handed on opposite sides. On the outside faces, have cutouts on front and back and mount two drivers wired in parallel for a bipole setup. This is no longer a wall mounted speaker but needs some cool looking legs to get it up to ear height. Kind of open baffle like but without a huge open baffle, just the cornu baffle, at 24, 28, 30 inches whatever you prefer. If you wanted to go nuts, make a really big cornu baffle to be about size as typical open baffles and get some monster bass with an 8 inch full range. I would do this with something like the Wild Burro Betsy at $100/pair. If you wanted to spend more on an 8 inch FR, maybe the Tang Band W8-1772. If you really want to cheap it out at 8 inches, do the Visaton 3020 BG20 (Sd is 214 cm2). Another slightly smaller option is to do a 6.5 inch full ranger. Has anyone tried the Visaton 3017 BG17 (93 dB efficiency for $16 ea)? The soundstage would be very big, and the bass would be killer. It would certainly be unique. What do you guys think?
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