The squeeze handle that tightens the bar clamp cracked exactly where you’d expect: directly across the pivot hole where the miracle engineering plastic thins down to a precarious ridge. The end of the handle is still inside the clamp:
Nothing bonds that plastic, so, in the nature of a quick fix, I cut a steel strap to wrap around the perimeter of the broken section and epoxied the whole mess together:
That lasted for exactly 2.5 squeezes and then pulled apart; the epoxy doesn’t really have anything to grab.
ABS isn’t a good substitute for engineering plastic, so this will require a bit of CNC work on the Sherline. I’ll probably carve the first one from polycarbonate, just because I have a sheet of the right thickness, but it really cries out for aluminum, doesn’t it?
Why CNC? Well, I’m going to make a handful of handles and get proactive on the other clamps.
My other bar clamps have much heavier sections in that area, so perhaps the folks supplying Harbor Freight could take a hint? Yeah, but the clamp was cheap, which always conflicts with good. On the other paw, I’ve seen exactly this same clamp priced at not cheap elsewhere.
The Smell of Molten Projects in the Morning 