Half inch drill bit for quarter inch drill?

A spade bit will be fine, as already explained. A caution: Somebody said they are grabby. They are. Very grabby.

Your drill has plenty of torque (turning power) so start slowly and enter the wood square to the surface. You should see a nice round even hole form as the bit enters. If not, just ease off a little and straighten up. Then continue into the wood. Advanced to medium power with the drill trigger and grip the drill with both hands. Get above it, if you can. Do not get the drill turning with more power than you can hold back if the bit grabs.

If you use only one hand to hold the drill, are turning at top speed, and the bit bites, you can break a wrist because the torque changes from turning the bit to turning the drill handle itself, to turning your wrist.

The risk of that is not high if you go slowly. Take your time and feed gently. All my scary talk is overly cautionary.

In no time you will have nice whole to mount your lamp. If you can put a pice of wood behind the planned hole, you can eliminate a lot of splintering there, on the back. If it’s out of sight, don’t worry about splintering.

Or drill the hole from one side until the center point makes a hole in the other side. Then drill from the other side using that hole the point made as a pilot hole.

That’s my two bits worth.

I hate spade bits. I would not use one for any purpose. They usually make a very messy hole. Forstner bits are usually used in drill presses. It’s possible to use one in a hand drill but it’s kind of tricky. I would use a reduced shank twist bit for this.

Agreed with the dislike of spade bits, though I’ve only ever had crappy ones without the edge spurs. So maybe some are better than others. Hole bits on the other hand are no problem, and twist drills (especially with a pilot hole) are very easy to handle under almost all conditions.

I would not use a spade or Forstner bit for particle board. Particle board is not like real wood. It flakes and crumbles. I’d use a twist bit or hole saw.

Whatever you use, Start drilling from one side until the guide point if the bit just pokes through the other side, then switch to that side. That will help eliminate blowout, which can happen in a very spectacular way in particle board.

Huh. I don’t get the hate for spade bits. I’ve never had a problem making decent holes with them. You have to be careful and go a bit slow to avoid splintering but every tool has its quirks.

If you don’t have to worry about a rough hole, use a dime to draw a circle on the particle board (it will be slightly larger then 1/2") , then use a small bit and drill a series of interlocking holes around the inside of the circle.

Whatever method you use, it’s best if you can have a scrap piece of wood clamped or held on the backside to prevent splintering as the drill breaks through.

The oak veneer should prevent flaking and crumbling.

I love this idea. I could do it tonight!

Yeah, i wish i could do that. I’m thinking duct tape would help, but there’s no way i could clamp a piece of wood there – not being able to clamp is why i need to drill a hole in the first place.

This thread is overcomplicating an entirely straightforward problem. Use a wood bit of the appropriate size for the hole diameter you want (a good self-feeding spade bit is perfect for the job and will make a nice neat hole through particle board). I especially like the spade bits where the cutting edges are curved upwards to a point, rather than being flat, because you get immediate feedback if you’re not holding the drill perpendicular to the surface. And it’s just really satisfying to see the hole taking shape.

A hole saw is much more likely to bind and I wouldn’t recommend it.

Can you link to a photo, because i don’t really understand what you are describing.

The spade bits looked like they’d be a good tool, until someone thought they would chew a mess into particleboard. But… Now that i know my little drill can do it, it does seem pretty easy.

Here’s an example (randomly googled) of a fancy spade bit with two features:

  1. The central spike is threaded (self-feeding), meaning that there’s no need to drill a pilot hole
  2. The cutting edges curve or angle upwards to a point at the outer edge, so that the drill inscribes a circle on the work surface immediately you start drilling. If you only see a portion of a circle, you’re holding the drill at the wrong angle.

spin_prod_209031901 (800×800) (shld.net)

Ah! I would have described that as pointing downwards, which is why i was confused. (Because I’ll be drilling down into my desk.)


I’ve never liked spade bits. They overheat easily and dull quickly. Their only advantage is that they’re cheap. YMMV.

I want to drill one hole, 1.25” deep. I imagine that even a mediocre bit will hold up for that.

I know I’m late to the party, and maybe you’ve already completed the project, but here’s one more:

When using spade bits, I’ve always had good luck drilling a pilot hole first.

I would mark where I want the center of the hole, then take a 1/8" drill bit and drill a pilot hole. Then use a 5/8" spade bit and drill the hole. Just make sure the smaller bit is as straight as possible when you drill the pilot hole.

There are several good ideas in this thread. You need to tell us which method you used!

Well, now that I know I can do it, I plan to order the monitor arm, and a monitor. But I probably won’t actually drill a hole until they arrive.

But I will return to let you know what I do

Lots of good advice already, but if you only use your drill very occasionally I’d repeat minor7flat5 and cincinnatus’s suggestions of practicing on a piece of scrap wood first, if you have any laying around. I cringe every time I see someone start to drill a hole by immediately pressing the trigger to the max instead of easing down slowly - I’m assuming that your 30 year old drill is variable speed since the reasonably cheap first drill I bought about 45 years ago (and still use) has it.

I have no scrap that will feel anything like the desk, but i do have scrap 2x4s lying around. That’s a good idea, to at least get a feel for the larger thing.

If practicing on scrap, please bear in mind that the torque of the drill can make a small piece of unclamped wood spin very easily and painfully!

Oh, i know that! I have used drills before. I was just wondering if i have a suitable way to clamp scrap wood in place for testing.