Chisel hole caculator, pricking iron hole ruler

When you have a pattern without chisel holes, or when you bending glue surface and lining leather together, the alignment of bending area chisel holes is always a headache. You can use this tool and awl to prick holes to solve this problem.

You only need have a kit of chisel and an awl to make all bags that have different chisel hole gap.

Here is a cartoon to show you how it works.