Home > categories > Minerals & Metallurgy > Aluminum Foils > Help designing a high voltage capacitorNot sure how to work the math backwards.?
Question:

Help designing a high voltage capacitorNot sure how to work the math backwards.?

I made a few caps for a project out of mason jars and did the math and they seem to be only about .05mf eachI need closer to 6.33I also need caps that can withstand about 10,000 volts so we decided to use 1/8th inch glass as the dielectricWere planning to use cut out pieces of copper on each sideHow much surface area would we need on each side to reach 6.33 mf? Would layering the glass and making a thicker dielectric increase or decrease capacitance? Would you recommend another method like tinfoil and wax paper with several run in parallel?

Answer:

Waxed paper is about 0.001 inch thick (0.0254 mm)Coincidentally, the page I found that gives this thickness is showing how to calculate the capacitance of a homemade capacitorThat's my first sourceUsing the calculator in my second source and the dialectric constant of kraft paper, I calculated that you will need about 7000000 square mmIf you use aluminum foil that is 12 inches wide, that's 305 mm To get the area needed, you will need your foil to be 22950mm longThat's about 23 meters or about 75 feet or 25 yardsMy roll is 66 yards, so to make two plates you will use most of a rollIf you want want it 15cm high to fit a mason jar (I don't have one to measure, so I'm estimating), that's about 51 yards longThe non-stick aluminum foil is coated with teflon, which probably will work as a nice, thin insulatorOh, noI just noticed the part about 10 kilovoltsThat won't work with waxed paper1/8 inch glass is 3.175mm and a different dielectric constantYou need about 900000000 square mmYou need a square of glass that is 30 meters on each sideIn other words, no.
Waxed paper is about 0.001 inch thick (0.0254 mm)Coincidentally, the page I found that gives this thickness is showing how to calculate the capacitance of a homemade capacitorThat's my first sourceUsing the calculator in my second source and the dialectric constant of kraft paper, I calculated that you will need about 7000000 square mmIf you use aluminum foil that is 12 inches wide, that's 305 mm To get the area needed, you will need your foil to be 22950mm longThat's about 23 meters or about 75 feet or 25 yardsMy roll is 66 yards, so to make two plates you will use most of a rollIf you want want it 15cm high to fit a mason jar (I don't have one to measure, so I'm estimating), that's about 51 yards longThe non-stick aluminum foil is coated with teflon, which probably will work as a nice, thin insulatorOh, noI just noticed the part about 10 kilovoltsThat won't work with waxed paper1/8 inch glass is 3.175mm and a different dielectric constantYou need about 900000000 square mmYou need a square of glass that is 30 meters on each sideIn other words, no.

Share to: