My first effort was somewhat mediocre, the casting sand just wasn't fine enough for smallish parts, so I decided to have another go, this time I used plaster to make the moulds. I managed to cast four sets before the moulds crumbled from the extreme heat. They still required a bit of time on the mill, finishing off on the belt grinder and then powder coating (thought I'd try a couple of different colours).
I decided to restore my Manfrotto to an alt-azimuth but needed a dovetail clamp, which is what started this, and decided to make a couple of spares and a smaller one for guidescope mounting (60* angle), plus a topmounting/carry handle for the 80mm scope.
Not up to Mr. Bunn's superlative workmanship but adequate for my needs.
