Get an angle gage and protractor and measure the angle of the joint. Subtract the angle you measure from 180 and divide the difference by two. For example, if the angle in your picture measured out at 160*, you would subtract 160 from 180 (20) and divide by two, or 10*. Set your chop saw at 10* and make your cuts. Joint should align perfectly.
Sorry, I can't help you with resizing picture.
Posts: 509 | Location: Rogers City, MI | Registered: Sep 25, 2007