How do I make spherical enclosures?

[rochmndx]

I'm seriously thinking about making spherical enclosures for my speaker project. Preferably, using concrete.

Anyone ever done this before? I can't quite figure out how to make molds and stuff.

Thanks in advance!!!

[flexus]

hi roch
i´m interested too in designing something spherical. if possible i would choose the seas Tr18. a coax is probably the only choice, or you take some broadband driver.
for the enclosure my idea would have been to take glass-fiber or sliced wood in shapes that build a sphere together. the fiber should be reinforced with wood too. no more thoughts about it at the moment.
greets

[John L]

I've forgotten the name of it, but there is a tube that is used for pouring cement columns,.......Spiro-tube, or something to that effect. It has been used several times recently by DIYers. I assume it is strong enough to work for you, and you can get it in different diameters too.

Oh, I remember, SonoTube. I assume that you can get it locally without any trouble.

[sharpi31]

I designed these for a project at work...

Fostex F200A in a steel sphere

Once damped these sounded amazingly fast and open. I wish I could afford a pair for use at home!

[drewmc]

Parts Express has a recent "DIY" project called the Shericals that uses cast enclosures.

Shericals

[cyclotronguy]

Nice low tech solution.

Get a sphrical object of a size your like.... stryo ball, beach ball or etc. Can't find the right size, then make one of paper mache.

Then lay up a fiberglass cloth and resin shell over the ouside of said object. Test first to be sure your resin doesn't ruin the form.

When done, either dig the form out of the shell or split the shell, remove the form and reglass the shell, adding driver mounting details in the process.

Cyclotronguy

[poynton]

Someone on the forum recently suggested wooden bowls from IKEA use in pairs to form a sphere.

Somewhere at home I have an article re:- building speakers from styrofoam spheres used in handicrafts. It used a small and medium for the tweeter and mid with a trapezoid box for bass.

[planet10]

Originally posted by poynton
Someone on the forum recently suggested wooden bowls from IKEA use in pairs to form a sphere.

The wooden bowls are probably only good for a 3 or maybe 4" (i have been sorely temped)... they also have larger steel ones. Somewhere on the forum is a push-push sub using the big steel ones. Lovely.

dave

[John L]

Ok, I did a google search on Sonotube and speakerbuilding and I came up with the following:

Building a Sonotube Subwoofer

Sonotube FAQ for speakerbuilding

This one is from AudioKarma, and is about 5 years old, Building an Acoustic Wave Cannon

Sonotube Sub Design Help

Where to buy Sonotube for building a subwoofer?

DIY Project # 11 - A Subwoofer Made from Sonotube and the Hsu 12" Driver - September, 1999

And from right here at DIY

Sonotube RL-p15 Project with questions...

"SDSS 1.1"
Single-Driver, Ported Tube Speakers

Ok, that should be enough for anyone as a starter. YOu can Google for more information. Just insert Sonotube in the search, and you will find much more.

[planet10]

Originally posted by John L
Ok, I did a google search on Sonotube and speakerbuilding

John,

SonoTube is good for building circular prisms, but i don't know how you'd use it for a sphere.

BTW the SonoTube people are quite aggressive about the use of the term SonoTube as a generic name for cyclindrical cardboard forms.

dave