Let me just preface this by saying that UV curable acrylic can be expensive and hard to get, at least the stuff that's actually made specifically for this use. I've found other UV curable materials that are much cheaper, and perhaps worth playing with, like UV curable nail polish (see Nailite
). It's probably unclear why you need a UV curable material at this point, but it will become evident later on.
The material used in professional manufacturing of hearing aids and IEMs, called otoplastik, is made primary by two companies (from what I can tell), Egger
, both of which are German. This stuff is on the expensive side, partly because they don't sell small quantities, but the pro-rated price (price of material per set of shells made) is actually only a few dollars, if that's any consolation. Dreve makes an acrylic lacquer, that is supposed to be used to "build up" a finished shell, but it's the smallest quantity available, 20mL for ~$30. You could probably make 3-5 sets of shells from that, depending on thickness. The material that is actually made for shell making is significantly cheaper in terms of $/mL but the smallest quantity sold is 91mL and that costs ~$60.
In terms of the materials needed, again, I've discussed/referenced a lot of this in my other 'Ible, so I'm not going to go into too much detail.
Also, while I will be focusing on showing you how to make hollow shells with the UV acrylic, I did make some shells using urethane epoxy, just as proof of concept (anticipating that most people aren't going to want to go through the hassel and expense of the UV acrylic route). So keep that in mind when reviewing the materials listed below.Materials
-Impression making kit
-Nailpolish (or lacquer paint)
-UV curable acrylic (available from Lightning Enterprises)
Balanced armature drivers (Mouser or Colsan)
Caps and resistors (if you want/need crossovers)
-Connecting wire (from IEMs to source)
-Hydrocolloid material (like gelatin)
-2oz disposable wax lined paper cupsTools
-Dremel (with lots of bits!)
-A helping hands
-Some long wood screws