Here is one I made, specifically for this post at this venue... although I have used it elsewhere. No precision machining, just stock hardware pieces welded and screwed together. I'll be using it again tonight. It's ugly, but effective.
http://taperssection.com/index.php/topic,83662.0.htmlI've been thinking about a DIY super clamp, specifically to wrap around balcony railing in the 1.5-2.5" range. Ideally I would want to hang an LSD2 out about 3 feet. That's a lot of moment weight so it would have to really grip the rail. Still at the thinking stage. I'm not sure if it is best to go with "V" jaws, or self tightening cam action like a pipe wrench. I want to respect the venue and not leave marks on their railing, so I'm thinking grippy rubber on the jaws.
Yeah, I know I can buy what I need for $50, but that's too easy.
God give us engineering degrees and welders so we can build shit.