I printed a 6 sided die from Thingiverse and then sanded it with 200, 400, 800, 1000 and 3000 grit paper and this was the result. I’m pretty darned impressed with that. When you wet the die, it looks even better than it does here (dry). The picture was taken with a macro lens on a DSLR, but I had to shrink it to 25% size to upload here. The die is 15mm.
I know people have made lenses with clear resin, but for this application, that level of dedication wasn’t necessary. 
Use some clear UV protection spray. You can then omit the sanding.
Yep, gloss clear acrylic or laquer spray paint will get you the same glossy wetted loos as the oil… but last longer.
You guys are right. We happened to have a can of clear spray gloss lying around, and I applied it to a 1" sphere that I had printed and sanded, and sure enough - it has that “wet” look permanently now. Thanks!
We’ll do the dice later - right now we’re busy painting the pips.
This looks fantastic! Clear can produce some incredible results if you’ve got some polishing time on your hands.
For something like that die you can polish it with a rock tumbler, probably using materials that aren’t as harsh since the resin will be softer than a rock would be (I think they use cork as a polishing material?)
Most 3D prints are too fragile for that, but something like what you’re printing would do fine.
I made a 2" sphere out of clear, then we sanded it just enough to get rid of the touch points and treated it with the acrylic spray. This picture doesn’t really do it justice. If you hold it up, you can see an upside-down image of what’s on the other side of it.
Here’s my attempt in 3D Printing an optically clear part for an EMES15 Laser Range Finder on my Tamiya #56020 Leopard 2A7+
