Curing 32mm hole alignment problems

Improving results achieved with a single-hole line borer. January 24, 2001

Question
I am doing full 32mm construction and have problems with locations of holes using a single line boring machine. Any advice?

Forum Responses
Here’s what works for us. We use Blum hinges and metabox drawers.

We reference all of our holes from the bottom front corner. We drill our first hole 48mm from the bottom and 37mm from the front. This makes the center of our bottom hinge 64mm from the bottom. This will flush your door with the bottom of the cabinet if you make your bottom hinge bore 64mm from the bottom of the door.

All of our hinge bores above the bottom hinge are done in multiples of 32mm from the center of the first hinge.

We have right and left hand fences on our hinge boring machine, with adjustable stops. The fence is marked in 32mm increments so that all hinges work in multiples of 32mm from the bottom hole. This way, the top hinge is always in alignment with your line holes.

Numbering the holes and using the numbers as reference markers can help.

Some prefer to use a balanced panel in which the cabinet sides are all cut in multiples of 32mm. With this system, you can drill your doors the same distance from each end, and all your cabinet ends are reversible.

With a single-hole line borer, you will have to reverse your panel and drill from the back. If your drill head isn't movable, you can use spacer blocks to get the right spacing for drawer slides, etc.

Be very careful to keep your machinery in alignment with the single line machine. Reversing the panels is a less accurate method than the double line borer, and it's easy to get out of whack.