Jodee from Inspire Woodcraft shared the woodworking tip featured in this video.
This short tip shows a reliable way to measure the lower portion of a counterbore so replacement parts or new mounting surfaces fit like the original.
The method focuses on finding the difference between a part’s overall thickness and how deep the counterbore actually is, then transferring that value to set a drill press depth stop.
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Why this measurement matters
Getting the lower half of a counterbore right ensures fasteners can engage properly without bottoming out or leaving threads unsupported. Jodee emphasizes that matching how the original part sat prevents binding and preserves the intended fit and function when making or replacing parts.
Tools and setup
The technique uses a set of digital calipers with a depth rod and a drill press with an adjustable stop to transfer the measurement. A scrap piece is used to mark and test the drill depth so the setting can be checked before working on the final part.
Measuring method
The core idea is to measure the internal depth of the counterbore relative to the overall part thickness so the remaining material depth is known.
By using the caliper’s depth rod and its ability to zero and re-zero, Jodee gets a direct reading of the difference without needing to physically disassemble or rely on guesswork.
This approach avoids guessing how much material must remain for the threaded portion and works regardless of whether the new tabletop or replacement part is thicker or thinner than the original sub-base.
Setting drill depth
Once the differential measurement is captured, it’s transferred to a step gauge or marked on a scrap edge and used to set the drill press stop. This ensures the counterbore is cut only as deep as necessary so threads engage properly and won’t risk bottoming out.
Tips and adaptations
The technique adapts to a variety of fastener sizes and mounting parts and can be repeated anytime a mating part must match an existing counterbore. Jodee’s method also works with other measuring tools that provide a reliable depth difference reading, and a quick test hole in scrap wood confirms the setting before committing to the final piece.
Conclusion
Measuring the lower half of a counterbore the way Jodee demonstrates removes guesswork and helps ensure new parts fit and function like the originals.
The method is simple, adaptable, and saves time by preventing mis-drilled holes and rework.
Support Jodee by visiting his online store here: https://inspirewoodcraft.com/collections/all.