From Amazon.
I was needing eyes that were clear so I could custom color a few pairs of Oldsquaw eyes. I bought some clear eyes from a taxidermy supply and they looked exactly the same as these cabochons. All I had to do was paint a black pupil and mix my own color from oil based enamel for the eyes, kind of a beige/carmel color for my oldsquaw. When I used to order real taxidermy bird eyes I was always waiting or not having the right color eyes. For a few years i was making a lot of foam crane decoys, about 600 of them, but couldn't really find an eye I was satisfied with and the cost would have been outrageous, so I got some 14mm cabochons and painted my own. I use an oil based paint pen for the pupil and then paint over that with rustoleum and let them cure for a week or two. I do not bed the eyes in anything like clay, I just cut the slot deep enough to push them in and apoxie sculpt over them and shape the eyelid with a pencil. If you are concerned about them staying secure, just try getting one back out. A tiny 1/8th paint brush is what I use to clear the apoxie off the glass while it's still wet. I just cut the end off sqare and it works really well to clear what the pencil doesn't and even shape the eyelids.
https://www.amazon.com/dp/B092CQSW1Y?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_3&th=1
Here is a collection of eyes I've painted for my decoys from cabochons. where are you going to get a 25mm yellow eye for a giant goldeneye. The wigeons with that goldeneye are oversized. The goldeneye is as big as my swan pattern. in the eye picture there is a light almost white eye for scoter, a yellow orange eye for redhead and ringer, a yellow eye for bluebill and goldeneye, red for wood duck and canvasback, a beige/carmel for oldsquaw and a 14 mm blended eye for crane, as well as the brown for a lot of the puddlers. I do straight up black eyes for some scoters.
My first foam decoys had wood heads, but I didn't like the weight and balance which made for a heavier keel. I started right where you are with no one to ask. The process continues to evolve and upgrade. Just about any decoys you see me post are foam. There aren't very many of us carving foam.
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