The sliding leg vice offers a great deal of versatility, offering the function of a twin screw vice, but at a variable screw to screw distant of up to 1.6m.
Video – The Leg
Feature 1 – Parallel Below the Shelf
The first problem I noticed with sliding leg vices is the parallel bar sliding along the shelf colliding with anything you were planning to store on the shelf. To overcome this, I put the parallel guide underneath the bench. To achieve this I reduced the height of the wheel brackets and raised the shelf. The trade off is to remove the vice you need to undo 4 bolts.
Feature 2 – Wheels
Typically people use a ‘V’ groove where the sliding leg moves wood on wood. My vice weighs 20-30kg, so this produced unacceptable friction. To overcome this I used 4×2” wheels.
-- Daniel - http://theloveofwood.blogspot.com/