Really enjoying the latest Math Monday at MAKE blog that shows off this great sphere made with 60 binder clips. It was designed by Yang Enqi and looks fantastic. Math Monday

I am looking for a solid, one-piece sphere inscribed in a cylinder. The cylinder needs to be semi-transparent. Something similar to this: http://www.crockhamhill.kent.sch.uk/teachers/History/AncientGreece/images/sphere_in_cylinder.jpg Any ideas on where I could get one, or who could create one?

Exactly what it says

I'm looking to build myself a globe but I'm having a little trouble. Most globes today have a single pivot that lets you rotate the globe along a single axis. I'm looking to build a globe/sphere that will allow you to rotate it 360 degrees in any direction. My grandpa used to have a globe that didn't have any pivots and that had a stand that you could place the sphere/globe on and you could rotate it anyway you wanted. I haven't been able to find anything close, and his got burnt down in a fire. I don't foresee the base being a problem, but I haven't really built any spherical shapes with wood as of yet and I am hoping you guys might have a few tips to help me on my way. I figure I should start with creating a skeleton of a sphere using at least three interlocking rings and go from there and see how sturdy it is. Any insight or tips are much appreciated.

Over at Make: Blog, George Hart shows that if you put a challenge out there, no matter how crazy, someone might just do it. So 15 years after he made some plans for a theoretical sphere made with 480 wooden pieces and 960 connections, someone actually built it. In this case it was Thomas Guethner of Trostberg, Germany. It's a ridiculous project to take on, but I'm happy that he did it, the results look great! Math Monday: Nailbanger's Nightmare

Hi everybody! I'm looking for a way to construct a hemisphere, - maybe 1.5" to 2" in diameter - ideally with no moving parts - where any of a number of areas on the surface could be magnetized at will I thought of having an array of tiny electromagnets starting from middle and radiating to under the surface, but frankly, that would take a long time, and I figure there would be insulation issues. Any suggestions?

 It could be one piece or separate at the equator, or have a hole in it. Also, it doesn't have to be exactly that size.

 Ok, I know how to figure the "volume of a sphere" and the surface area of said sphere,  now I need to know how to figure how much I need to remove from the outside, to reduce the volume by about 1/2.   I suspect this will NOT reduce the size of the entire sphere by 1/2....at least, that doesn't seem logical to me. Can anyone explain it so that I (not a mathematician) can understand it?  

I've downloaded Pepakura and I can't figure out how to do it. My ultimate goal is to make Peas in a pod out of sheet metal for my wife. I've made the pod (and figured out how to work with, and weld sheet metal in the process. I don't know how I'm going to make sheet metal spheres about the size of baseballs. I've seen on "how it's made' how they used flat sheets of paper, die cut them, and then kind of folded them over a hemispherical form to make half a globe. I just need that pattern. Anyone? Thank you! Steve

I want to make a bad-ass globe, but don't even know where to begin.

I am collecting data in the form of old pics, patents, newpaper and magazine articles as well as just doing things.Tesla coils are fun but is anyone experimenting with the original "multiplying transformer" that Tesla created?And before you say, sure I have a Tesla coil......I mean:Large diameter primary coil with one part of the secondary in very close proximity while the other half of the secondary is located at the center ;)

I am planning on a project and I need to know how to make a huge hollow sphere? I was thinking about using paper mache around a huge sphere, but dont know where to start, like what would i paper mache around. I would like the sphere to be about 30"-40" in diameter. Even though Ive said it, please remember it needs to be about 30"-40" before you answer your question. Thanks!

I would like to build an okama gamesphere from southpark  to use as an enclosure for a project and while i have no problem playing around with different things for the base of the system im having a hard time coming up with an idea of how i would make the sphere iv found some clear plastic spheres that might work great if i could make them the right color i figured that while i continue to rack my brain over it id throw it out there in case someone has done something similar and would have some idea of what would be good to buy, whether its a green sphere or something i could use to make a clear one into a green one   would love any input from any direction 

Hello all this is my first post on Instructables so thanks for taking the time to read ! I am looking for ideas on how i could manufacture a perfect, hallow, fibreglass sphere measuring around 4 metres in diameter (BIG) :) I have experience with using fibreglass but I am running out of ideas for how to make a plug on this scale and get it to be perfectly spherical... It has to be made from Fibreglass so i am really asking for help on making the mould. ANY help or suggestions would be gratefully received no matter how wacky ....I am willing to try anything. If your idea works I will be more than happy to name the first of these epic spheres after you !! All the best  Ben

I need to make a hollow sphere for a project that is supposed to look like a bomb. Any ideas?

I know that naturally this doesn't exist. However what if i was to take two identical domed magnets and attach them to each other (not sure how I would do this) shouldn't this create a magnetic sphere with north on the outside and south on the inside. As shown in the picture. Thanks

Hey All, I'm getting ready for my next project, making a Deadmau5 head that replicates his pinhead helmet from last halloween. Since this helmet will require "messing up" and texturing the head rather than using fabric, I was assuming I'd use styrofoam to create that effect. However, I am uncertain as to whether or not I should be buying a hollow styrofoam sphere or flexible styrofoam, or something else. Any help/guidance would really be appreciated. I will be putting the material on a 13" hamster ball. Thanks in advance!!

Hello, all.  I bought a nice pendant lamp for my house several months back from one of the local big box stores on clearance.  I only got around to putting it up recently, and when I opened it (yes, I already feel stupid for not having opened it right away to check on it...), the main glass lamp shade was completely shattered! Sadly, the lamp was on clearance because it had been discontinued, and none of the stores in Canada have any of them in stock anywhere, so getting replacement is impossible. I really like the lamp, though, as it matches several of the other lights that my wife and I have purchased, so I figured that I would try my hand at making a replacement shade!  The shade is shaped as follows: it is a section of a sphere 19.5" across (the diameter of the section, not the of the entire sphere), and 5" deep.  A little math (x^2 + y^2 = 2yr) lets me know that the radius of the sphere that this shade is a section of is 12". Here is my plan, and I would like to know if I am crazy or if anyone has a better suggestion.  I am going to try to cast a replacement shade from polyester resin, 1/4" to 3/8" thick.  I was going to make a 2-piece mould from plaster, and use my wood router suspended from a gimbal (on a 12" radius arm) to cut the outer mould.  Similarly, I would suspend a plaster blank from the gimbal over my router (on a 11 5/8" radius arm) to cut the inner mould.  Then I would simply coat the two halves with mould release and pour/pump the resin into the gap between the halves.  I'll tint the resin with some dye to get it the amber colour that I want, then lightly sand to get a smoky translucent finish. My only questions are: 1)  will I be able to get this mould apart without destroying the resin casting, and 2) will polyester resin be strong enough for this kind of casting?  Another option would be to make a wooden mould, but I thought that I might be able to chip away a plaster mould, whereas a wooden mould would be a lot harder to get off of a stuck casting! Thanks!   PS, of course, if this works, I'll post an instructable of it!

Does any one know where to find this backgroung in this video? If you do please leave a comment with the link to it. THX Charger_06

I'm trying to make a "tesla cane" (just a cane topped off with a working plasma sphere) for my cousin's steampunk-themed wedding. I already have a USB Plasma ball (Model is here: http://www.thinkgeek.com/geektoys/science/964e/?), and I'd like to make it run off battery power. I'm good at soldering and dealing with small wires, but I've never measured voltage or anything like that. Advice? Has anyone attempted a project like this before? It seems like there are tons of "convert batteries to USB" tutorials but not many of the reverse. :)Thanks in advance!

I need to know what size sphere Nickademuss used in his 900,000 volt van de graff generator.

There's a preprint out today which uses archival infrared astrometric data from IRAS to set limits on the existence of actual Dyson spheres within 300 pc of the Solar System, a volume which includes roughly 106 solar-type stars.

This is for an adaptation of a lamp. What I want is to cover the bulb with a large (little smaller than a basketball) sphere, so there will be a hole in one end. Light obviously needs to be able to shine through. My first thought was a resin of some sort, and a quick search led me to epoxy resin. Is this see-through? Can colour be added? Any other ideas? Some early thoughts: - In an inflated balloon, inject liquid. Rotate, thereby distributing fairly evenly, until liquid hardens. Cons: How long do I have to rotate this balloon? What if it pops!? (Could use a hard container...) - Double boiler: Use two similar bowls, small inside larger, fill in between. Cons: How to get it even? Smaller bowl would float (weigh it down...) Not even close to a sphere With your suggestions I'll do a few trials, possibly put out an instructable if something works. All suggestions are welcome (even if they deviate a little). Thanks!

The most I've gotten is it's a "sphere within a sphere and there's a bell", but I don't want to cut one of mine open. Is it an ancient chinese secret.? I thought it might be like a rain stick with thin metal soldered to the inside surface with a loose ball to strike them.

Can I use a sphere magnet when building an EMF PUMP? Glued onto the pulley. Thanks

I'm trying to decide what kind of grinding media to use for crushing powders in my ball mill. Is it better to have different sizes? Also, is it true cylinders work better that spheres? My two main choices are either brass balls or alumina cylinders, which one should I pick?

  Rice Cooker Burger Robot Zombie Figurine Cup Sphere Lamp Resurrect a Motorcycle Make Bath Bombs Cheap Masquerade Masks Hybrid Solar Panel Arduino on a Perfboard Rope Bridge Bookshelf Upgrade Your Promo Camera Iron Man Make a Talking Clock Coffee-Stained Coffee Table Simple Microscope Webcam Make a Garden Fountain  

Hi, I'm currently in Year 10 and we have been assigned to make a USB lamp. Now, I'm fine with the assignment only I cannot think of how to shape my idea realistically. I wanted to make a cannon shape, with a sphere like bottom before it curves into a thin neck. However, I don't know how to make the plastic bend into the sphere like shape. It's really difficult and I'll include a picture of my idea if it helps!

The globe will be painted by young children for a recylcing themed parade float.

A question came up the other day when playing with Buckyballs of how you manufacture spherical rare-earth magnets. I'm surprised they could use that name, given the original Buckyball, but these Buckyballs are powerfully magnetic spheres with one side a North pole and the other a South pole which can be stuck together to make 2D and 3D structures.  Sale has been restricted in many places because of people ingesting them and requiring emergency surgery. I've found information on neodymium magnet production using a sintering process, but can't see how you could produce a perfect Ni/Cu plated sphere with this method as individually machining to a sphere would be excessively laborious and tumbling would be a non-starter because of the attraction between balls.  EDIT: The sintering page wasn't the one I thought I was linking, but the one I've linked looks like it may have the answer in die-pressing or isostatic pressing in the aligning field of a solenoid.  Is this how it's done for spherical magnets? (Polishing the coated spheres would still be a problem.)

I'd like to make a sheet metal ball, maybe two inches in diameter. I've seen on "how they make it" (or some show) that they die cut paper for globes and then form the cut paper over a cardboard hemisphere. The paper is die cut in a pattern so that the cut pieces come together to form the hemisphere with no creasing or folding. I've googled with no answers (at least that I could find). Thank you! Steve

Hi, I'd like to know if there's a sensor easily used with an Arduino that detects the signal strength of a sound of frequency determined by me. I want this to make a sensor that can be used to measure its distance to the emitting object omni-directionally, ie, not like ultrasonic or IR distance sensors, which only sense what's in front of them. I want the sensor to sense the SPACE AROUND it, like... spherically. If you know of a sensor that does that in another way, I'd LOVE to hear about it. I've been searching for something like that for a long time... Anyway, I just need a sensor - cheap, preferably :) - that senses the signal strength of a wave of frequency x. By the way, the distance range to be measured is about 10 - 150cm... Thanks!

The original Sputnik looked really slick and threatening! I want one! Unfortunately, the original is unavailable, so I'll have to settle for something more modest. The original Sputnik looked like the one in the picture. My goal is to make a model that is life-sized and pretty good looking. Coolness is paramount; precision and accuracy are not. Does anyone have ideas about how to make the sphere part easily? The criteria for my model sphere is that it needs to be:     Roughly 60cm in diameter (I believe the original was ~58cm)     Strong and rigid enough that I can attach the four antennas     Light enough that I can hang it from my ceiling     It is okay to be a little rough (i.e. it doesn't need to be polished steel or whatever) Right now I'm thinking I should get a bunch of pieces of hard-cell foam, stack and glue them, and carve a sphere. Then I'll sand it smooth and spray paint it silver. Is this a good approach? Any other ideas for the project?

If I can't use a fan, wat can I use while keeping it perfectly sphericle? It also has to sort of control itself with voice comand overide

I need help to make a round mold for wax spheres but i dont know how i need them the size of marbles

I want to make a two piece reflective (on the inside) sphere big enough for a person to comfortably stand in. What would be the best way to go about this?

I have a old glass sphere from a plasma globe and I was wanting to use  again but i need the circuit I need it if I want to use it again

1).  I would like to use PET drinking water bottles  and polyethylene plastic bottles ( taco Sauce, mustard, plastic juice bottles)- for insulation in an  attic? Choice 1). using a heat source like a heat gun and my air compressor can I inflate old PET plastic water bottles - into balloons to act as insulation spheres ?   Each week  I would spend time turning the plastic bottles into thin-walled spheres that would fill up the attic with light-weight spheres- maybe the size of a soccer ball?  . 2). If Not  choice 1). lets learn how to process plastic bags and packaging into a shredded stringy material to do the attic insulation job. The source of bottles is endless and I hate recycling these to the city and then purchasing expensive fiberglass batt insulation at $40 per roll.  Any DIY wizards try this stuff?  I could literally mega-insulate the attic. If treating the material with Sodium tetra-borate  borax -to get a fire resistance that is doable too. They make clothes, blankets, molded items and padding routinely from old bottles: Why can't I? I would build a shredder or modify a branch shredder machine to do this and make it my recycling hobby over the long term.

I was thinking about getting some thermo plastic. However, I wasnt sure if it would get creases in it if used over a spherical surface. If theoritically I put some thermoplastic over a bowling ball, would it match the curve of it? Thanks! -xD

I am looking into creating a virtual reality experience controlled by something like the VirtuSphere (www.virtusphere.com).  I know there are giant hamster balls out there, but they are inflatable so I don't think they would be strong enough for what I want to create.  Also, solid balls would be waaay too expensive (like the BuzzBall or a Zorb).  Ideas? 

Just for fun, I created a few physics simulations in blender, All of them of a building getting knocked down with various objects(meteor, plane, car, spheres). Here it is Here is my first one, It is older And included is a screenshot of the second simulation! :D Tell me what you think :) Thanks ~ReCreate

I was trying to answer a question earlier and wanted to put in the formula for figuring the surface area of a sphere.  Short of adding an image, I couldn't figure out how, so I just wrote out the formula. Is there a way to insert math symbols in the answer box?

I've decided i want to make a R2D2 for Halloween. I'm pretty sure i can make most of it from scrape metal but i don't know where i can find something that's like the head on R2D2. I need a metal sphere that i can cut in half, any ideas?

Can i use van de graff generator to kill incests or i can kill rats......if yes how it works........what material should be belt made of??and is it necessary to keep sphere more distance from lower belt roller...................??

If you had, say, light from a torch or whatever, directed it through a metal pipe or fiber optic to get it kind of directional, and then into some arrangement of lenses; what kind of maximum range could you expect before it completely lost focus? And would it still obey the inverse square law, or is that just for expanding spheres of light?

I don't understand why my instructable, the sphere lamp, isn't in the coffeecup contest anymore. Is it because of the use of plastic cups? Because as I mentioned it was intended with paper cups but I didn't had those available. If so, why didn't I got the message about disqualification at first and are there other instructables in the contest which only have plans about using paper cups but no cup was used? Will it help if I rebuild it with paper cups?

I want to know if you can calculate the capacitance a Tesla coil semi spherical top load by calculating what it would be then halving it? Also if that is possible could you third it or quarter it because I am going to buy metal bowls for it and most aren't quite a semi sphere (a lot only go about 120 degrees)? 

I have searched all over the internet for a simple how-to when it comes to making those sphere-shaped lanterns , and no one seems to have bothered to do any. I'm interested in making some large ones but the first attempt didn't have that clean round look. Has anyone made one or know of a tutorial? Hopefully one with pictures or video.  thanks!

I'm looking at building an indoor firepit that uses ethanol fuel. I have it all planned out and everything but need advice on material. It will basically be a hollow sphere that is open along the front and sides and will have the ethanol fuel can placed into the bottom. This will all be supported by wooden legs. I'm thinking of using a clay straw and sand mixture (COB) because it's very strong and fireproof  but I'm not sure if it's the best option. Does anyone have any ideas?