Finished up a build on a '98 Shadow Aero last spring, and finally getting around to doing a custom key for it...Lady rider and loves dragonflies..
Made a silicone mold from a section of wooden dowl rod that I sanded the edge down a bit, then mixed up a tiny batch of two part casting resin and poured it into the mold and let it sit for 6 hours...Then placed a dragonfly charm I got off ebay into the mold and mixed up another small batch of resin and poured it in, let it cure for another 6 hours...Came back to it and mixed up more resin, but this time mixed in some "snowflake" pigment to give it a nice background...
Now for my "learning experience"...The wood dowel plug I made, I sprayed it with some polyurethane and let it dry a few days before making the mold...Found out after making this piece that the polyurethane didn't exactly play well with the silicone...And when I pulled the plug out it didn't leave the impression in the mold perfectly smooth...I was able to pour a tiny bit more silicone into the bottom to level it out, but couldn't fix the sides without starting over from scratch...So after the part fully cured and zi popped it out of the mold, the sides were a little rough..Sanded the outside edge with 600/800/1000/1500/2000 and finally 3000 grit wet/dry and then hand polished it the best I could...It's not perfectly clear on the side as it is on the front, but going to go ahead and fit the key into it today...Might leave it as-is, or I had the idea of mixing up a little bit more resin, stick the key into a cardboard box and pour the resin onto the "knob" and let it "waterfall" over the edge and that will make it crystal clear (I already tried it with water and it cleared right up)...