I'm going to look around a bit more for the L brackets since my problem may just be not looking hard enough, but if I can't find them by this weekend, I'll send you an email.
To be honest, my work is so ultra-low budget that I can't even afford real 3X3 filters so I'll probably just use circular filters and buy a used cokin system (I know, I know...) off ebay for ND grads, etc. so I for one would definitely be interested in plans for a rail system. If there's a way to make one with 15mm rods, I assume other people would be, too, simply because the "real thing" is so absurdly over priced.
To be honest, my work is so ultra-low budget that I can't even afford real 3X3 filters so I'll probably just use circular filters and buy a used cokin system (I know, I know...) off ebay for ND grads, etc. so I for one would definitely be interested in plans for a rail system. If there's a way to make one with 15mm rods, I assume other people would be, too, simply because the "real thing" is so absurdly over priced.