
This will also determine the length of the tenons on your rails. Determine the depth of the groove for your panel. Keep in mind that these are 1.5 and 2.5 inches wide respectively. Most DIY flat panel doors are made with 1×2 or 1×3 stock. Or you can use a nonstandard measurement, but if you do you will have to rip the stock to width yourself. You can use standard 1×2 or 1×3 or 1×4 stock for your rails and stiles. Rails run horizontally (like a hand rail) and stiles run vertically. The rails and stiles are the vertical and horizontal pieces that make up the outer frame of the door itself. Determine the width of your rails and stiles. At this point, you just need to know what size to build your doors. More could be said about overlay, inset, and partial overlay/inset doors, but that is a discussion for another post. This means the length and width of the doors should be 1/8 inch less than the overall opening. If they are inset doors, meaning they fit inside the face frame opening, you will allow for 1/16 inch gap on all 4 sides. This means they overlapped the face frame on the hinge side by 1.25 inches. The last doors I built were 1.25 inch overlay doors. You may need to have the hardware picked out prior to building. This will affect the hardware you purchase. If they are overlay doors, meaning they overlap the face frame opening, determine how much overlay. If you are building all new cabinetry, you will simply need your final measurements based on whether they are inset or overlay doors. Measure and write down those measurement, being accurate to 1/16 of an inch. They could vary by a fraction of an inch here or there. Simply measure the length and width of each door. If you are replacing existing doors, this is easy.

How to build flat panel cabinet doors on your table saw.
