These steampunk goggles are designed to use 52mm photographic filters as lenses. I used cheap ND8 filters from dx.com which cost about $6 each.
The auxiliary lenses with the sweet orange coating were salvaged from a found pair of cheap binoculars.
The strap is a makeshift solution - made from black fabric tape (somewhat like duct tape) folded over on itself. A strap with a bit of stretch would be an improvement.
I printed with PLA using a raft and support on makerware and a Replicator. Support is essential to support the outer ring and the auxiliary mounting lugs.
The bridge (over the nose) is printed separately, and clips into the outer ring of the goggles.
If you printed in PLA, the bridge can to be warmed and bent to adjust how the goggles fit to your face. I poured some boiling water into a bowl to heat the bridge to pliability.
I also used hot water to push-fit the little auxiliary lenses into their mounts. Obviously you can use the aux lugs for whatever you want, or leave them empty.
I painted the buckles with copper Liquid Leaf paint. They looked fine unpainted too.
The strap holes are designed for a strap up to about 25mm wide.
I was able to thread the lenses into the eye pieces without glue. If your sizing isn't spot on you could hot-glue the lens in place. The ideal solution in my mind would be to use two pairs of filters, remove the glass from one pair (by unscrewing the locking ring) and hot-glue just the threaded rings into the eye pieces, then screw the other filters into the rings. Because the filters can be stacked, you can add polarizing lenses on top if you want.