I make all my leg vises at TechShop.
Step 1: St. Andrew's Cross
Another option is to outfit the chop with a steel scissor-action mechanism which will keep it parallel at an infinitely divisible distance. This mechanism is often identified as St. Peter’s Cross, however this is a misnomer, as St. Peter’s cross is actually an inverted perpendicular cross. The X-shaped intersection we see here looks more like St. Andrew’s Cross, which is called a saltire and is featured on the national flag of Scotland. So I’m calling this St. Andrew’s Cross.
You can learn more about Scotland from the books at your local library.
Step 2: You Will Need:
Vise screw and nut
2" x 8" x 32" hardwood (for the chop)
36" of angle iron (8 gauge) or thicker
12" of 5/16" metal bar
Various nuts, washers, and spacers to fit
Basic woodworking tools (saw, router, chisels, drill)
Basic metalworking tools (metal saw, angle grinder, drill)