Mold for casting epoxy eyes?

mount a row of already made eyes on a flat surface.... build a box around them about an inch high.. spray with mold release and pour in some RTV silicone. The next day, pull the silicone out, and presto.. eye mold. Smooth on is a good place to find everything. Even hard plastic to make the eyes....

I made a mold using thumbtacks and regular household RTV.

Lay a piece of Waxed Paper on the small edge of a piece of 1X2. Poke the thumb tacks into the paper/wood as far as they will go leaving about 3/16" in between. Spray with Pam.

I used a large tube of RTV and a caulking gun to lay a heavy bead of RTV compound down the entire length of the mold-to be. Make the bead continuous and as fat as possible--one single bead end to end.

After a short time, I flipped the 1X2 over on to a piece of Waxed paper on a flat surface and lightly pushed it down. This gave the mold a flat bottom.

My mold would make a dozen eyes at a time and used about 1/16 of a tube or RTV.

I've used clear acrylic for the eyes as well as "Hell of High Water" epoxy. I am sure you could clear RTV also but you'd probably loose clarity.

The hardest part of making the eyes is centering the peel and stick eyes in the drop of epoxy. It was such a PITA that I decided to use just the plain stick on eyes.

If you figure your time is worth $5/hour, it is cheaper to buy the eyes over the counter.

If you need any "Wiggle eyes", I have thousands I'll give to anybody who wants some.

Two thoughts:
#1 you might look into the plastic "wells" used in bioscience labs to hold serial-dilution aliquots for immunoassays - do not know if they're available in various size(diameter) ranges. Each square can have dozens of pre-cast wells.
#2
Bob Ransom, who originated the "fender fly", used Dritz sew-on snaps in various sizes to make his own eyes:
he'd 'assemble' the snaps(through the prism tape 'fender'), then 'peen' the central 'nipple' with something like a small tack hammer, so the two pieces were 'welded' together . He'd then lay out the 'fenders' on a strip of tape, and fill each cavity with epoxy tinted with acrylic paint/glitter. After the 'fill' puddles were mostly set, he'd go back with a very small dowel & add a small drop of black-paint-dyed epoxy for a pupil. Provided you apply something to 'plug' the little holes on the back side of the 'female' part of the snap so the epoxy won't drip out, I see no reason why you couldn't do this to make individual eyes without attaching them to the prism tape, so you could use them on any fly.
If you have Angelo Peluso's "Saltwater Flies of the Northeast", I have a fender fly in that book with eyes made using Ransom's original technique.
This method was first described in Fly Tyer magazine back in the Winter, 1989 issue ; Also in Phil Camera's book "Fly Tying With Synthetics" (Voyageur Press, 1992 -- ISBN: 0-89658-174-8 )

Wow .... I am impressed.

I never think of hot glue. One question regarding hot glue, is there any that is really clear?

BTW, your use of modeling clay will work. You can skip a step if you buy Fimo (Maybe it is Femo.) This clay can be baked in an oven and produce the mold in one step. Imbed the eye forms, pull them out and bake the clay.

If I can find some clear hot glue, I might make some eyes again. Otherwise, it is just too much trouble.

My wife is one of the very smartest people I know. (She caught me, didn't she?)

She read over this thread and suggested gluing a few "Wiggle Eyes" to a piece of Formica. Spray with a release compound like PAM then push the Fimo down over them. This would give the top of the mold a flat top and all eyes would be identical. Carefully remove the Fimo from the eyes and Formica and place it on a cookie sheet and bake as directed on the package.

I haven't seen clear hot glue but I have some in various metallic colors. I've used my glue gun as an injector to fill lead molds to make very light jig/lure heads. I hope clear is available.