Large electromagnetic coil for Iron filings

I am an artist working with darkroom photography, working directly on photosensitive paper without a camera ( photograms ) I have been creating images by placing ceramic magnets under photographic paper and sprinkling iron filings on the paper surface in the darkroom and exposing to light in the normal manner. I am limited by size and would like to build some large electromagnetic 'rings' maybe the diameter of bicycle tyres down to diner plate size ones. They need not be very strong but a few formulas to follow with the insulated wire gauge , length, number of windings and power supply to safelyexperiment with to get me going would be great, I am not good with maths but am a good DIY tinkerer ! any tips/help would be gratefully received thanks Remco

Electronic Design Elektrisk ingeniørvitenskap

Prosjekt-ID: #20085150

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