Knife Cad is an app for designing and viewing the mechanics of folding knifes. You set the size of your blade, handle, pivot pin and stop pin in inches. The app will draw these rectangles and circles in proportion to the sizes you entered, then allow you to draw your own blade and handle design. You can watch the blade open and close to make sure that your design works the way you want it to. You can adjust the size and position of the pivot and stop pins, then re-test your design. You can add up to two stand off pins of the size and location of your choice. When you are through designing your knife you can print your design for using as a template to make your knife. If you don’t have Air-Print or want to save the design for later use you can attach the PDF file to an email or message then save the attachment.