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A rolled capacitor design using aluminum foil as the conductor and saran wrap as the dielectric is deemed effective for the materials available. The design should incorporate a one-inch spacing around the edges of the foil to prevent arcing. A paper roll can serve as a suitable mandrel for rolling the capacitor. Additionally, the paper can be utilized as an outer covering for added insulation. This approach effectively incorporates all provided materials while ensuring functionality.
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Hi! I have to build a capacitor out of the following materials: 10 square feet of aluminum foil, 10 square feet of saran wrap (polyvinyl chloride), several sheets of paper, and tape to put it all together. I will only have about 30 minutes to manufacture my design. I have been researching capacitors and so far the best one I have come across using my given materials is a rolled capacitor. Is this accurate? Or is there a better one I have not come across? For this rolled capacitor I would probably only use the foil as my conductor and the saran wrap as my dielectric because, to my knowledge, it has a much higher dielectric strength than paper. The reason I am second guessing my design is because it does not use one of my given materials, paper. Is there a way i could work this in? Or a different design that uses all of my materials? Thanks!
 
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I have decided on the rolled capacitor, but now I have more questions. How much spacing should leave around the edges of the foil on the saran wrap to avoid arcing? Is one inch sufficient? Also, I saw something about using a nonconductor like glass or plastic as a mandrel to lay in the center and roll up in the capacitor. Would a paper roll work well as this? Thanks again!
 
One inch border should be fine. The plastic wrap would probably punch thru long before you reach a voltage to flashover two inches!
An additional way to use the paper is as an outer covering.
 
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