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I recently acquired some odd sized mica diaphragms. Is there a way to cut to size? If so what is the process without damaging the edges?

Thanks everyone!

Anyone??

it's very difficult as mica is very hard in the flat plane but cleaves easily in the horizontal plane , but you can try using a compass ( Drawing tool ) by placing a steel needle in the "drawing" side and going round and round till you go through the entire mica it does work and the mica is OK to use even if the edge isn't perfect

soundgen wrote:it's very difficult as mica is very hard in the flat plane but cleaves easily in the horizontal plane , but you can try using a compass ( Drawing tool ) by placing a steel needle in the "drawing" side and going round and round till you go through the entire mica it does work and the mica is OK to use even if the edge isn't perfect

Thanks for the info!!

Soundgen's note reminded me that you can buy compasses fitted with blades. I have one I bought decades ago, it is Japanese and I used it to cut paper circles. The blade is replaceable and of high quality, so I would think it will be effective to cut mica, but I never tried to do so. You can find these if you look for origami tools.

CarlosV wrote:Soundgen's note reminded me that you can buy compasses fitted with blades. I have one I bought decades ago, it is Japanese and I used it to cut paper circles. The blade is replaceable and of high quality, so I would think it will be effective to cut mica, but I never tried to do so. You can find these if you look for origami tools.

like this I guess , be great to know if it works on mica

https://www.graphicsdirect.co.uk/produc ... gI6uPD_BwE

Oooops, reiterated!

Mmm i don't like mica diaphragms with peeled borders... i like'em with perfect borders...
I thinnnnk they must clinnnnk clear as a bell when dropped on a hard surface by the edge, just 1" fall on the table from your fingertips... That reveals the sound it will have when reproducing. The higher and cleaner the clinnnnk , the better it will sound.
You can call me maniac!

If you can find a compass similar to the one pictured by Soundgen, you can place an Exacto knife in it instead of a pen or pencil, which will definitely cut mica. Also, if you place the mica on a flat surface with a piece of double sided tape below, it will keep it from spinning when cutting. Covering the edges with Scotch tape before cutting may stop the edges from fraying during cutting. Some people have also used a compass to draw a new cutting line and then cut it with very sharp scissors and it supposedly works fine.

I've tried this recently using a cutter compass, and even though I was using a new sharp blade, the end result was heavilydelaminated around the edges. The blade was cutting the mica one layer at a time, rather than going through it all at once.

A good stopgap measure, but best to find a diaphragm that's the right size and spare yourself the hassle