I developed the vise jaw spacers depicted on the left by accident. Originally, I was going to make spacers that are similar to those Clay Spencer uses. However, in the process of thinking about how to make them, I came up with design pictured above. Here are construction notes on how to make them.The spacer on the right is a more robust version. The wedge has a width going all teh up to 1 1/2". It revolves around an aluminum pipe and the pipe is attached to the vise jaws by two strong magnets. The magnets are attached through a slot and secured with cotter pins. This allows some movement of the magnets and prevents the spacer from falling off when the vise is operated. Most post vises are not precision tools and have quite some wiggle room. It should be noted that the spacer, due to its increased weight is quite heavy. If you would like to learn more about it, please let get in touch with me.