Karmiruuvipora Procat 14 / 5 mm

A frame screw drill or frame bit is a drill bit meant for drilling holes for adjustment screws in door and window frames. The frame screw drill makes a narrow through-hole and a wider clamping hole in the frame at the same time. The bit has a removable tip that you can take off with an Allen key.

Pick the right size frame bit for your screw. Then drill a hole in the frame so the smaller bit goes all the way through. The bigger hole should stay well inside the frame so it doesn't split when you tighten the clamping screw. You can drill the bigger hole a bit deeper if you're using shorter adjustment screws. Then sink the adjustment screw into the hole and tighten it to the tension you want.

For drilling screw holes in frames
Storage case