Have you ever needed to drill an exact depth? As you might expect, there are a variety of tools that allow you to do this.
Drill presses are designed to drill an exact depth over and over again, but they can be pricy. Depth stops are also used to drill an exact depth, and are an affordable accessory that can be used with a drill bit and drill/driver – tools you probably have!
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What are Depth Stops?
So, you’ve heard of depth stops: but what are they?
Depth stops, also called drill stops, are collars that fit around your drill bit. They allow you to drill a specific depth, and prevent the drill from drilling any deeper. Drill stops are sold in sets containing a variety of sizes for use on different sized drill bits.
Drill stops sets are very affordable. This set of seven from Home Depot costs around $18 at posting.
They do a great job of stopping the drill from drilling further, although be aware that the collar itself often leaves marks on your wood when used.
If you have a good sander, it’s not a big deal to sand these off, but if you don’t you might want to slip a piece of scrap plywood underneath the collar (and adjust the depth accordingly) to prevent that from happening.
A variety of depth stop sets are available on the market… but for most of “diy-career” I didn’t own one. Read on to find out why!
How to Use a Drill Stop
Drill stops are really easy to use – simply slip the collar over the drill bit, and place it at the required depth.
Then tighten the collar with a hex key, and drill your hole. The collar will prevent the drill from drilling any deeper than the collar.
The mechanism for tightening the drill stop might look a little different than mine, but they all operate with a hex key. Here’s what the mechanism looks like for the drill stop that came with my pocket hole jig:
Drill stops can be used with other types of drill bits too, however you’ll need another accessory to make it work. For use with a Spade or Forstner bit, use a collar that’s about the same size as the shank (usually 3/8″.)
Grab this “jig it” drill guide from Rockler and slip it onto the shank of the bit. Then slip the drill stop around the shank and tighten it at the correct position.
Combined, these two things will stop the drill from drilling further when you reach the required depth, and also help you drill a perfectly perpendicular hole.
Note that this does require an “extra long” bit.
DIY Depth Stops
Now, for a really long time, I didn’t own a depth stop. Why? Because it’s easy to make your own. And as the lovely commenters on my Youtube channel have informed me, I’m “really cheap.”
First, determine the length of the drill bit that will be sticking out of the wood when you reach your desired depth. Then cut a piece of scrapwood that length (see picture below.)
Finally, drill a hole using the drill bit you’ll work with through your piece of scrap wood. Insert the piece of wood onto your drill bit.
Boom. You now have a drill stop.
The advantage of this method is that it can be done with any size drill bit. You might note that the depth stop sets only come with 7-ish sizes, but there are a whole lot more drill bit sizes than that.
Creating your own depth stop avoids that problem, since you’ve customized it for the drill bit size you need.
And I don’t know about you, but I have more scrap wood sitting around then I could ever possibly use.
P.S – You can also use this method on Spade and Forstner bits… just drill a hole the diameter of the shaft, and slip the wood on before you drill.
Remember, the piece of scrap wood you use will need to be larger than the diameter of the hole you’re drilling!
Other Drill Stop Alternatives
Making your own DIY drill stop isn’t the only option – there are some other easy options if you don’t need perfection. And of course, there are a few other tools that are excellent at drilling holes at a specified depth.
Mark with a Marker
If your depth doesn’t need to be perfect, say, you just need to not go all the way through the wood, using a wet-erase marker to mark the drill depth on your drill bit is an easy alternative.
This hack is exactly like it sounds. Grab a marker, and mark where to stop drilling on your bit. Then when you drill, don’t go past that mark.
I recommend a wet-erase marker so that the mark doesn’t rub off while your drilling, but you can still erase it later so you don’t end up with a bunch of marks all over your drill.
But if you only have sharpies/permanent markers… let me share a teacher-hack with you. Use that to mark your drill bit, then grab some alcohol (or a whiteboard marker) and rub that over the sharpie mark. The ink should come right off.
(FYI, it is not uncommon for students to accidently write on the whiteboard with a sharpie. They panic about it, but I just rub an actual whiteboard marker over it, and everything is fine.)
If you don’t have a marker around, putting a bit of masking tape at the desired depth works too!
The downside to this method (and the reason I think the marker is better) is if you need to make repeated holes, the masking tape gets torn up pretty quickly.
The other reason I didn’t own a drill stop kit is that I inherited-ish a drill press. (By inherited-ish, my Dad inherited his father’s nice drill press, and I was given the less-than-great Harbor Freight drill press.)
And drill presses are really, really good at drilling a specific depth over and over again. That’s kind of the point (along with keeping the hole perfectly vertical.)
Most have a built-in depth stop that’s easy to work, and given your piece of wood can fit on the drill press, it’s probably the best option.
If your piece can’t fit on the drill press table though, that’s when other options are needed.
Plunge routers are really good at drilling holes of a specified depth.
The downside is that they’re not that good at drilling the holes particularly deep, since router bits are really short.