Deal Extream 100mW

I recently purchased a DX 100mW and was wondering how i could make an IR filter and if its possible to open the case without wrecking the laser.

Well, you could take the IR filter out of a old webcam. You can open DX lasers by putting the silver cap where the beam comes out of into a vice grip (Put some blocks of wood around it if you don't want to scratch the end), and pull slowly while twisting. I do not know where/how you would put the IR filter in, though.

This page has some good reading about newwish lasers (The kind dx sells, fake or not).

Assuming the fact that your old webcam has an IR filter