Deep hole drilling: 5 checks

The fitting hole is visible, but the felt tip’s body prevents its tip from touching the wood: the mark becomes approximate, and the assembly shifts. To understand how to transfer deep mounting holes, you must first check access, then immobilize the part, reach the support, mark without deviation, and check positions. This guide describes transferring a small plate onto a board placed on a workbench. It does not replace the choice of appropriate fastening or the necessary checks before wall drilling.

1. Prepare the support and check access to the hole

Place the board on a stable workbench and position the plate in its mounting direction. Identify the holes that will actually be used for fastening: an adjustment opening, a cable pass-through, and a screw hole do not have the same function. Consult the part’s diagram or instructions when their role is not obvious.

Then observe the path to the wood. Its depth, diameter, and shape determine whether the marker tip can reach the support without being forced. A tip advertised at 20 mm does not guarantee access in all thick parts: the body may butt against a recess, and a narrow hole may jam the metal part before the bottom.

Remove dust, shavings, and grease stains according to the support’s finish. Test the ink on a comparable scrap, never in the middle of the visible face. Check that the point remains legible and does not spread into the fibers. A dark or very porous surface may require another marking method. Do not assume that the marking will be erasable: place the marks in the future hidden or removed area.

2. Immobilize the fitting in its final position

Measure the part's position from a straight reference edge, then check its orientation. For a rectangular plate, two measurements taken from the same edge allow for detecting a misalignment. Do not try to compensate for an alignment defect by tilting the marker afterwards: this would shift the future holes without correcting the assembly.

Hold the fitting with an appropriate means, for example, a small clamp equipped with protection on fragile surfaces. The clamping must prevent slipping without deforming the part or obscuring the openings. Check that the board itself does not move on the workbench. A cramped hand on an unstable part does not offer a reliable reference, especially when several holes need to remain aligned.

Test the marker's path before applying ink. Your wrist should be able to stay aligned without hitting the clamp or the edge of the furniture. If a fastening gets in the way, reposition the hold, then retake the measurements. Prepare all points before removing the fitting: moving and then replacing a plate after each hole unnecessarily multiplies the chances of misalignment.

3. Reach the support with a sufficiently long tip

A long-tip construction marker works here by contact. The thin part passes through the hole, and its end touches the wood. The principle of the precision marker presented by edding illustrates this access to difficult areas. It should not be confused with a projected chalk marker, whose mechanism and capabilities are different.

The Manuzen model has an advertised 20 mm tip, a 13.7 cm body, and black ink. Insert it gently, in line with the passage, until it contacts the support. The body should not be used as a lever on the edge of the hole. If the tip does not reach the wood, remove it: forcing it risks damaging it or causing the fitting to slip.

Also check the centering. In a hole wider than the tip, pressing systematically against a wall produces an off-center mark. Look for the center intended by the fastening's geometry and keep the same axis. If the exact location remains impossible to determine, use a template or an appropriate centering device rather than turning a dubious mark into a definitive hole.

4. Transfer deep mounting holes without shifting the points

Make a brief mark in contact with the wood, then withdraw the tip along the same axis. Unnecessary circular movement enlarges the mark and obscures its center. You are looking for a usable reference, not a stain that overflows under the plate. Maintain a natural grip and avoid pressing too hard on the tip to get more ink.

Move to the next hole without shifting the hold. If the first mark does not appear, check on a scrap piece that the marker still writes and that its tip is clean. Do not shake the product or pump its tip by analogy with another type of marker: follow the instructions on its packaging. Each mechanism requires specific actions.

Side lighting can help distinguish contact at the bottom of an opening, but it does not make a hidden area accessible. Do not slide your fingers into a sharp metal passage to guide the tip. For a part with oblong holes, identify the desired adjustment position beforehand; marking the end of a slot when the assembly requires its center distorts the entire preparation.

5. Check the transfer before drilling

Remove the hold, lift the fitting, and examine the marks. They should be clear, distinct, and located in the intended area. Compare their distances with those of the holes, then reposition the part to check for correspondence. This second check is essential when access prevented direct viewing of the tip during marking.

If multiple marks overlap, clearly identify the correct one before proceeding. Do not drill in the middle of a smudge hoping the screw's play will correct the error. Review the fitting's placement, distances to edges, and mounting direction. For repeated parts, discreetly number the supports: two visually identical fittings may not have exactly the same center-to-center distance.

The validated transfer does not define the drilling diameter or depth. These parameters depend on the material, screw, and assembly. Remove the marker from the work area, then prepare for drilling separately with appropriate holding and protection. Close the cap immediately after use; the Manuzen set contains four black markers, to be kept out of reach of children, without leaving their tips exposed in a pocket.

To remember: to transfer deep mounting holes, the right marker must reach the support without deviating, but an immobile fitting and a final check remain essential. Consult Manuzen measuring and marking tools to prepare your marks before drilling.

Guide documented on September 12, 2026. Illustrative scenarios; always check the instructions and the chosen variant.