Sorry I hadn’t visited this thread before now, but on examining the photo of the jack screw, I count only about 2.5 turns of thread on a 20 thread-per-inch screw extending through the jaw. If the screw is indeed screwed all the way in, that’s only 1/8″ and is simply not going to work for blades more than about 1/16″ thick. My WE100 vise screws were altered about ten years ago, so I can’t speak to what the correct length is, but certainly it should be at least 1/4″ longer. An e-mail or phone call to WE customer service should get you the right stainless steel screws. Meanwhile, I’d pick up a couple of regular screws at your local hardware store to tide you over.
In the second photo, I see what seems to be the upper screw extending almost completely through the threads of the upper hole. Are your screws both the same length? Hopefully, you’ve already solved what seems to be a simple problem.
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