How to Control Drilling Depth With a Handheld Power Drill

Drilling depth control starts before the bit spins: decide where the hole should end and mark that point on the bit. A stop collar or a fitted wood block physically limits how far the bit can go. Tape or a marker line only shows you where to stop, and both work better than trying to slow down at the last second.

The right limit depends on the hole. A blind hole ends inside the material, so you set the limit at a measured depth from the surface. A planned through-hole is supposed to come out the far side, so the back face is your endpoint.

Set the Stop Point Before You Drill

Pick the endpoint first, then set the limit to match it. Follow this sequence for any hole where depth matters.

1. Decide what kind of hole you need. If the bit must not come out the back, you're drilling a blind hole. If it should exit the far face, you're drilling a through-hole, and the steps change at step 6.
2. Measure the target depth from the entry surface. The hole depth is how far the bit travels past the face you start on. For example, if the hole needs to be 1 inch deep, measure 1 inch back from the bit's cutting tip and treat that spot as your stop point.
3. Set your limit at that measurement. Fit a collar or block if the bit must physically stop there. Use tape or a marker line if a visual cue is enough. The next section explains how to set up each one. If you work with a small craft drill, our guide on using a precision power drill covers inserting bits and choosing a speed before you add any depth limit.
4. Test the setup on scrap. Drill one hole in a scrap piece of the same material, then measure its depth. If it's too shallow or too deep, move the stop or marker and drill another test hole until the depth matches.
5. Drill to the limit, then stop. For a blind hole, stop when the collar or block meets the surface or the visual cue reaches it. Before each new hole, check that the stop or marker hasn't moved on the bit.
6. For a through-hole in wood with a brad-point bit, stop at the first sign of the tip. Fine Woodworking describes a brad-point method that prevents tearout: drill until the point just peeks through the back. Then turn the workpiece over and finish from the reverse side, using the pinhole as your center point. Use this method only with a brad-point bit in wood.

Set a Physical Stop or Visual Marker

Choose a method based on whether you need a solid mechanical stop or a quick visual reference mark:

Use a physical stop when going too deep would ruin the part, like a blind hole close to a finished back face. The collar or block keeps the bit from going deeper even if your attention slips at the end.

Tape is quicker to set up and works for one-off holes where a little extra depth won't cause damage. Because tape can shift, look at where it sits on the bit before each hole instead of trusting it all session.

FAQs

How many holes can I drill before tape stops being reliable?

There isn't a fixed number. In Fine Woodworking's repeated-hole observation, tape becomes unreliable after five to 10 holes. Treat that as one shop's experience, not a rule. For a long run of identical holes, a physical stop holds its position better than a visual cue you have to keep checking.

Does tape work as a depth marker on spade bits?

Not very well. This Old House's wide-bit advice says tape doesn't work well on spade bits and other wide bits. Instead, draw a permanent marker line on the metal at the stopping point. Like tape, the line only shows you where to stop. It won't stop the bit.

Can a steel stop collar damage my workpiece?

Yes. WOOD Magazine warns that steel stop collars can mar a wood surface. When the collar reaches its limit, it presses against the face you're drilling. On a finished or show surface, keep that in mind before you pick a steel collar for depth control.