Half inch drill bit for quarter inch drill?

I have a drill that has a bunch of bits, the largest of which is 1/4 inch. I need to make a hole through a desk (Looks like very thin oak veneer over particle board) that should be about 1/2 inch diameter. I’m making it to mount a monitor arm, if that matters. And the hole can be as large as 2" in diameter.

Can I buy a drill bit that makes a half in hole that will fit into the chuck of my existing cheapo drill? Will trying to use it burn out the drill?

Alternatively, would it be possible to buy a tiny hole saw rather than a giant drill bit? Might that work with my existing drill?

I expect to make one hole like this ever in my life, and I’d just as soon not buy a new expensive drill for the experience. I’d also prefer not to try to find a handyman to drill a single hole. It’s hard to hire contractors, and it’s hard to imagine a smaller and less interesting job than "drill a hole in this piece of particle-board.

(And no, Discourse, this is not similar to topics about quarterbacks.)

Yes, you can. You just need to buy a drill bit that’s 1/4" in the part that goes in the chuck and 1/2" in the part that actually makes a hole. It may be called a reduced shank drill bit. You’ll find this in any hardware store.

Yeah, you can get cheap hole saw kits, like:

It’ll fit fine in your drill. 2" should be no problem even for a weak drill. The depth is only 1", which might be enough, but if not you can go from the bottom up as well.

The quality won’t be great, so you probably want something to cover the raw edges. The base of the monitor arm should accomplish this, I’d think.

Yes, the hole will be completely covered by the base of the monitor arm, so it doesn’t have to look pretty. The base is about 7 inches wide, and 3 fore-to-aft, so it’s going to completely cover the hole.

Also, this is great news.

Which is likely to be better, the huge drill bit or a small hole saw?

While drilling, drill bit or hole saw, periodically (3-4 times a minute) lift the cutter slightly to clear some of the dust from the hole. Easier on the drill motor AND the cutting face.


Drill bit will prob work better for you - the hole saw will exert a lot more drag, and will absolutely demand to enter the wood at a right angle. Otherwise snagging and binding, and good chance of the motor being wrenched from your hands.


The desk seems to be about 1 and 1/4 inch thick, fwiw.

Depends on the bit. Hole saws will do the job just fine. For bit drill bits, there are spade bits, which I don’t really recommend, especially in the larger sizes. There are also Forstner bits, which I have no experience with, but I suspect aren’t too tricky to use. There are also step drills, but they only work for thin materials and aren’t useful for this purpose.

If this really is a one-time thing, and you don’t expect to drill any holes of any kind in the future, I guess I’d go with the Forstner. It’s about the same price as a set of hole bits, but will probably do a slightly better job.

ETA: a self-feed bit like this one might be better yet for your purposes, if you aren’t totally comfortable with your tools. The screw tip will guide it in to a large extent.

Oh, I have a drill because I sometimes drill holes. But I’ve had this drill for 30 years, and never before felt the need for a bit larger than 1/4 inch. I expect I will never again need a bit larger than 1/4 inch after this one use.

That looks nice, although the smallest is 1".

The requirement is a hole at least 1/2" and no more than 2". And actually, the minimum size is smaller, the 1/2" gives a little slop in case the hole isn’t exectly perfectly vertical. So I’m inclined to lean towards the smaller size, unless it’s somehow easier to make a larger hole.

Forstner bits are primarily used for drilling holes in 2X4s for running wiring. They can drill a hole very quickly, but the hole will be somewhat rough, and they have a tendency to “catch” and twist the drill.

A standard 1/2 inch drill bit would work nicely, but I would probably only use a drill that has a chuck that accepts at least a 3/8 inch bit (preferably a 1/2 inch chuck).

As has already been mentioned, a cylindrical hole saw may be the best bet for a 1/4 inch chuck.

Ahh, sorry–I misread your intent. I thought that you needed to make holes as large as 2", but really that’s just an upper bound.

If 1/2" is sufficient, you have more options. A hole saw will be fine, but even a standard twist drill might work. I think this would be fine. I’d drill a pilot hole with an existing drill to help guide it in.

Spade drill bit with a 1/4 inch shank:

Ooh, that look like it might be perfect. It will probably chew up the surface a little, but as previously mentioned, minor rough edges will be hidden by the base.

Nah. A nice new sharp spade bit will cut a clean hole. If the surface is a different material than the rest (like a laminate) it may chip a little, but you can minimize that by making it not the top surface. A layer of masking tape is usually good enough.

I don’t think you’re thinking of Forstner bits. They drill clean, flat bottomed holes, but aren’t particularly fast. They’re also reasonably expensive, as mentioned by @Dr.Strangelove.

I love Forstner bits, but for this application, I’d use a 1/2” twist with a 1/4” shank.

As mikecurtis says, a new spade bit should do a clean job of it.
Make sure to get a good one that has little spurs at the edges to score the hole as it drills (the one linked above has these spurs).

You will need to be careful to hold it perpendicular to the surface. Do a few test holes in a piece of scrap wood first. The aforementioned masking tape is definitely a good idea.

Oops, you’re correct. I was thinking of an auger drill bit.