I originally wanted a larger vise, but the cost of steel was a problem. I could have gone larger, but the place I was ordering the pipe from started charging a LOT more for the larger diameter stuff. I kinda wish I was friends with a plumber who could give me some scrap material to work with This will work with up to a 2.050" knife, which will handle the types of knives I currently make. If (rather, when) it becomes a problem I may end up building another one that has a larger opening.
Yeah, the springs are great. When opening the jaws I just twist the adjustment knobs and they get pulled up automatically. No fiddling around with manually lifting them up to shove the knife in. I stole borrowed the idea off of someone who posted a similar design I found on Reddit.