This jig was simple to build and greatly speeds up carcase construction where you need to repeatedly set dominoes in rows across wide panels, such as bookcases or cabinets.(see pic#1) The first step is to mark the distribution of domino mortises you wish to cut across the panel on the panel end (for this demo I only spaced three across an 18" panel). Transfer these marks for spacing your dominoes on to the jig's cross bar. (see pic#2) Obviously you only need do this once for most projects. . I use masking tape on the bar so as to keep it free of permanent marks. All you need do then is mark the center of your rows of mortises where wish them to be on the panel. (see pic#3) Insert the panel in the jig and align a row mark with the permanent center scribe mark on the jig (see pic#4) . Clamp panel in place and your set to go. You align the center line on the domino machine with the marks you transferred to the masking tape on the cross bar and make your cuts (see pic#5 - 9) . Simply unclamp and move the panel to the next domino row centerline on you panel. then clamp and repeat.