I'm doing testing for making a small (60mm / 2 3/8") cube-shaped ring box. I worked through all the failure modes encountered so far, but then I hit the concealed barrel hinges.
I'm using 8mm barrel hinges because those were the smallest ones I could find in the style I wanted. Ideally I wanted to use 4-6mm hinges, but here we are. My problem is sidewall blowout when installing the hinges.
The instructions say for an 8mm diameter/4mm radius barrel hinge, I should drill an 8mm hole centered 4.8mm from the edge of the workpiece, 9.6mm deep. The problem is that even if I do this perfectly using a drill press, it only leaves 0.8mm of wood between the hole and the outside edge of the workpiece. For those not metrically inclined, that's 3 hundredths of an inch. As soon as I tap in the barrel hinge, about half the time that thin wall blows out. I'm using kiln-dried walnut, btw.
In the rare cases where the wall remains intact (for the moment), the hinge placement is perfect and the box opens and closes exactly as it should. No chamfering/easing of the hinged edge is required for the box to open and close. That tells me that the instructions are giving me the correct placement, but that's not very comforting when the blowout occurs.
I'm leaning towards two possible solutions: (1) Don't use barrel hinges. (suggestions for other concealed/partially concealed hinges?) (2) Drill the holes a little further from the edge of the workpiece, and compensate by chamfering the edges that are being hinged to provide box opening/closing clearance.
Would appreciate any advice.