It's acrylic so it's good to go. Acrylic is inert to skin.
Home-Made IEMs - Page 111
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OK. I've completed another set of CIEMs. Basically they are clear acrylic shells with Astrotec AX35 monitors in them. If you didn't know, the Astrotecs are affordable ($70) hybrid monitors with a dynamic speaker for the low spectrum and a balanced armature for the highs. Sound-wise, they are much better than my Sennheiser IE-4 and my Knowles dual driver designs. The Astrotecs are physically a bit large in the shell but I made it work. The dynamic speaker is much more suited for the lows and it really shines in the CIEM shells.
So I did some experimenting with the different UV acrylics I've used and here's my verdict. The $5 nail salon stuff from Ebay looks, smells, flows, and cures just like the expensive Loctite stuff. That's what I'll use from now on. So total cost of the best CIEMs I have; less than $80.