Selecting Wood Drill Bits For Installers

Avatar
Ari Erenthal
Published Nov 29, 2016 14:49 PM

Running cables through studs is common for roughing in residential and some older commercial installs. To do this, you will need to drill holes in the studs and this requires wood drill bits, such as twist, spade and auger bits.

This guide will help you understand the different types of bits designed available and the tradeoffs of each.

Selecting **** ***** ****

** * ******* *****, ***** *** the *********:

  • ***** **** *** *** ********, **** commonly *********, *** ****** *** ****** to **** *****.
  • ***** **** *** *** ******* ****** *** drilling ***** ***** **** *** ******** less ******** ******** ** ***. **** are **** ***** ** *******.
  • ***** **** *** *** ******* *** drilling ***** *****, ********** ** *** or ******* ****, *** *** **** expensive, ******* ******* ******** ******** *** proper ***** *******.
  • **** *** **** **** *** ***** but *** *****

Drilling **** *****

** ***** *******, *********** ********* *** commonly ***** ****** **** ****** *****. A **** *****, **** ** ******** treated ****, ** ******* ** *** *****, and * ****** *****, **** ** standard *****, ** ******* ** *** *******, with ***** ****** ***** **". ***** studs *** **** ** * ***** to ******* *** ******* **** ***** up *** ****. 

*** *** ***** ** ** * 3/4" **** ** *** ****** ** a ****, ***** ** ***********, *** still **** ** ** ** ****. According ** *** *** (***.*), "************ ***** ** **** *** **** of *** **** ** *** **** than * */* **. (**.* **) from *** ******* **** ** *** wood ******. **** *** ***** ** North ******* **** *** *** *****, which, ** *** **** *******, *** 3.5" ** *.*".

** *** **** ** ***** * 1" **** ** ******, *******, ** if *** **** *** ***** *** hole ****** ** *** **** ** the *****, ***'** **** ** *** nail ****** [**** ** ****** *********] to ******* *** ****. **** ****** are ***** *** **** ** *******, and *** ********* * **** **** even ** *** ******** *********.

Twist **** 

*** **** ****** **** ** ***** bit ** ****** * ***** ***. It ** * ***** *** **** a ***** ******* **** *** ******, sharpened ** * ***** ** *** end. *** ***** ** **** ***** greatly ******* *** **********. *** ***** angle for ******** ******* **** ** *** degrees. **** ***** *** **** ***** in **** *********** ****** **** * tip ***** ** *** *******, ***** work **** *** ****** *********, **** metal. *** ******* **** **** *** wood, *** *** **** **** ** exert **** ******** **** *** ***** have **** * *** ****** ***.

***** ******* **** ***** **** **** fill **** ***** *******, ******* ********** ** remove *** ******** *** *** ******* times ****** ******** ** *** ***** side ** *** ****. ** ***** are ************ ********, ****** *** *** and ***** *** ******. ** *** even ** ********* ** ***** *** hole ******. **** ****** **** * **** that ****** *** **** *** ***** to **** **. ** ***** * hole ****** **** *****, ****** *** the **** ** *** **** *** pull *** ***** *******.

* ***** *** **** ** **" long *** */*" ***** ***** ~$** USD. 

*** ********* ** *** ***** *** concept ** *** **** ***** ***, sometimes ****** *** ***** ***** ***. Instead ** ** ****** ***, ** has * ******* ***** ** *** center. **** ******** *** *** **** wandering ***** ******** *** * **** efficient ***** ******. *** ***** ***** remove ***** ******, ***** ** **** ***** the *** ****** *** ****** *** bit ** **** *** **** ***** for ******. 

* **** ***** *** **** ** 12" **** *** */*" ***** ***** ~$15 ***. ***** **** *** **** difficult ** *********.

******* ******* ** *** **** ****** bit, **** ****** *** ********* ***. This ** * ***** *** **** a **** **** ***** *** * hole **** *** ***. **** ****** you ** ***** * ****, ****** a **** ** *** ***, *** then ******** *** *** **** * wire ********, ******* *** **** * wire ****** *** ******* * ***** hole. 

**** ****** **** **** ** * wide ******* ** ***** *** *******, and ***** ~$** ***.

Spade ****

***** ****, **** ****** ****** ****, allow *** ** **** **** **** holes **** **** ****** **** **** a ***** ***. **** **** * center *** *** *** **** *******, and *** ***** **** *******. ***** bits **** ** ******** **** *******. When ***** ***** ****, ********* *** direction ** ***** *** **** ** pulling **** *****, *** ***** ** that *********, ** *** ********* ***'* interfere **** **** ******. ***** **** bind **** ****** **** ***** ***** ** bits. ** ********* ******* **** ***** to ***** ****** **** ****** *** safety.

* */*" ** **" ***** *** ***** ~$** ***. **** ***** ***** *** designs ******* ***** *** ********** *** are ********* ** ******* **** **** become ****. 

Auger ***

** ***** *** ****** ** ********* to ***** * *** ** ***** very ******* **** **** ****** ******. It *** * ***** ***** *** which ******* *** *** ******* *** an ****** ***** ****** ********* ***** forces chaff ***. **** ***** ** ***** ***, choose **** **** ********* *** **** sure *****'* ******* ** *** ***** side ** *** ****, ******* *** self-propelling ****** ** *** *** ***** it ***** * *** ******* ** stop **** ******* *** ****. 

* */*" ** **" ***** *** *****~$** ***.

*** ******* ** *** ***** *** is ****** *** **** *****. **** bit *** * ***** ********* **** a ******** *****, *** ** * good ****** *** ***, ****, ******, or ******** ******* ****. **** **** auger **** *** **** **** ******* nails ******* ******* *******. **** **** than ******** ******, ***** ***** "*****" with * **** *****. ** *** use * **** *****, **** **** you **** **** ** ** *** other ****. ** **** ********* ***** two ***** ** *** *****, *** one, ***** * **** ****** ** possible.

* *.*" ** **" **** ***** bit ***** ~$** ***. ***** **** ** ***** type *** **** ********* ** *******.  

**** ***

* **** *** ** * *********** two bits ** ***. ** ** * ring *** ******** ****** * **** twist ***, ***** ** **** ** drill * ***** ****. ** ** highly efficient ** ******** * **** **** hole. ** **** **** * **** cleaner **** **** * ***** ***. However, *** *** ** *** *** leaves * **** ***** **** ** removed ****** ***** *****, ****** **** the ******* ***** ** ***. **** bit ** ********* ** ******** ***** in ***** *** ***** *** ******** at ******** ***** *** ******. 

* *-*/*" **** *** ***** ~$** ***.

Where ** ********

**** ******** ********* **** ***** ****. Home *********** ******, **** ** **** Depot, ***** ***** ** ********* ********** of ***** **** ** ********* *****, lengths, *** ******. ******* **** ******** lose ************* ** **** *** ****, some *********** ******** ***** **** ** consumables ******* ** *****, *** ***** their ******** ***********.  

Comments (33)
Avatar
Brian Karas
Nov 29, 2016
IPVM

However, the cup of the bit leaves a plug which must be removed before using again, making this the slowest style of bit.

Most installers here may already know this tip, but in case not: when drilling with a hole saw, if you "wobble" the drill as you drill it will cause it to cut a hole with a wider kerf, which results in the plug that is left over in the hole saw being slightly smaller than normal, making it way easier to remove.

Also, this quick change arbor makes it easy to remove the hole saw to knock out the cut-out (even though the review gives it only 1 star, it's always worked perfect for me):

(1)
(1)
Avatar
Ari Erenthal
Nov 29, 2016

I never got the quick change thingy to work. Maybe it's me.

MI
Matt Ion
Nov 29, 2016

There are several different quick-change designs; some work better than others.

U
Undisclosed #1
Nov 29, 2016
IPVMU Certified

Is there any kind of wood bit that is not difficult to sharpen?

(1)
Avatar
Ari Erenthal
Nov 29, 2016

Standard twist bits are not difficult to sharpen. I used to sharpen mine all the time using a cut off wheel. This helped me extend the life of my twist bits considerably. In fact, I used to cut my twist bits down to 118 degrees as soon as I bought them.

U
Undisclosed #1
Nov 29, 2016
IPVMU Certified

I used to sharpen mine all the time using a cut off wheel. This helped me extend the life of my twist bits considerably. In fact, I used to cut my twist bits down to 118 degrees as soon as I bought them.

Isn't that (118 degree) what make them non-standard and hard to sharpen in the first place?

Avatar
Ari Erenthal
Nov 29, 2016

The angle isn't what makes it hard to sharpen. It's being able to sharpen it in the first place. Most bits have ridges, nooks, edges, sticking out parts, and other features that make it difficult to sharpen with any tool larger than a Dremel. The twist bit, however, is just one flat plane. That means you can hold the cut off tool in one hand, the bit in the other, and just freehand it. I used to just eyeball my cuts. It took a while to get the hang of it, but eventually it became second nature.

U
Undisclosed #1
Nov 29, 2016
IPVMU Certified

That makes sense.

...and just freehand it...

Probably won't try that. I don't speak tool as a first language, but only due to fate. In high school, because I was late signing up for electives I missed out on "body shop", ending up in "typing 101". I've been trying to recover ever since, but...

And the bits I use now rarely go dull, but occasionally with a long, flaky cable, the 1's will start losing their point and get rounded down to 0's. Really hard to sharpen, too.

(1)
(2)
Avatar
Ari Erenthal
Nov 29, 2016

That's what we're here for, education!

UI
Undisclosed Integrator #2
Nov 30, 2016

And the bits I use now rarely go dull, but occasionally with a long, flaky cable, the 1's will start losing their point and get rounded down to 0's. Really hard to sharpen, too.

Funny stuff! I can relate, Thanks for the laugh.

U
Undisclosed #1
Nov 30, 2016
IPVMU Certified

That means you can hold the cut off tool in one hand, the bit in the other, and just freehand it. I used to just eyeball my cuts.

Used to eyeball them.

Because now he just uses the Force!

Avatar
Kyle Folger
Nov 29, 2016
IPVMU Certified

I use the Milwaukee Switchblade for prewire. It makes holes fairly well. I would have linked to Milwaukee's site but it wasn't pulling up at the time of this post. I have the quick change bit extension as well. If there are a lot of holes a corded drill works best but I haven't had enough holes to justify the Hole Hawg.

(1)
Avatar
Ari Erenthal
Nov 29, 2016

Interesting. Is 1-3/8" the smallest size available? Does it bind a lot? It seems like it would. Do you need a side handle to control the drill? Is it easy to use from the top of a ladder?

MM
Michael Miller
Nov 29, 2016

The trick is to set the drill on low speed and let the bit do all the work. Hole Hawgs work best and yes a side handle is nice to have. Just don't get your hand pinched when you hit a nail.

Where these are most useful when you have multiple studs to drill through which holes saw can't accommodate.

(1)
Avatar
Kyle Folger
Nov 29, 2016
IPVMU Certified

I haven't hit many nails with it. I generally don't need to use them on ladders. They don't bind like a paddle bit would. As Michael said they work well through multiple studs. It's one of those items that I carry and only use when necessary but I always keep it in the truck.

MM
Michael Miller
Nov 29, 2016

Don't forget Self Feeding Wood Bits which can be more useful then hole saws.

(2)
(2)
MM
Michael Miller
Nov 29, 2016

These work really well with a Hole Hawg until you hit a nail.

Avatar
Ari Erenthal
Nov 29, 2016

See, that's why I like auger bits. They eat nails without stopping or binding.

Avatar
Ari Erenthal
Nov 29, 2016

I've never used a self feeding bit on a door, which is the only time I use hole saws. How precise of a cut can you make with them?

MM
Michael Miller
Nov 29, 2016
Mostly use these when I central vac as you had to drill 2+inch holes for the pipe. When sharp these are faster then hole saws.
Avatar
Kyle Folger
Nov 29, 2016
IPVMU Certified

On a door I would prefer a hole saw and for a clear cut drilling from the opposite side when the pilot bit pokes through. I know forstner bits make clean holes as well.

(2)
Avatar
Brian Rhodes
Nov 29, 2016
IPVMU Certified

On the issue of bit sharpening, drill bit material plays a key role in addition to geometry/rake angles.

High Speed Steel (HSS) bits can be repeatedly sharpened and take an edge, but dulls with use pretty quickly.

Solid carbide bits are often too hard to be sharpened successfully. They stay 'factory sharp' longer (even through heavy use), but typically cannot be resharpened for more than a hole or two.

In some cases, HSS bits are coated with some sort of carbide-like coating. Once that coating is gone, the underlying bit can be resharpened, but it dulls quickly.

(1)
(1)
MI
Matt Ion
Nov 29, 2016
(1)
(3)
Avatar
Ari Erenthal
Nov 29, 2016

Safety note: never, ever grab the tip of a drill bit! It may be hot. Get your apprentice to do it, that's what they're for.

(3)
Avatar
Michael Archer
Nov 30, 2016

3d Drill Bit

Even since I found this kind of drill bit, called a 3d Bit. From of all places a shopping channel. QVC many years ago. I never bother with any other bit.

The nature of this bits means it never slips, you can turn and twist to drill at angles, even 45degree ( great for pipe work ) and also can move it in directions. And also cut at edges which would otherwise not be possible unless on a bench!

Maybe someone can locate as I only know source for UK where to get.

My original set I had lasted me for over 20years. Even used smaller size to cut into tiles for cables! (shower cable, not cctv!)

(1)
UI
Undisclosed Integrator #2
Nov 30, 2016

Wow, that looks really cool! I'd love to take those bits for a test drive. I couldn't really find any place online to purchase them...

Avatar
Michael Archer
Dec 01, 2016

If you take a copy of the image and save to PC HDD. You can do a google image search, it will show many results with the same image, you may be able to locate somewhere, sorry I'm not sure of your location.

I just did this and link is too big to post into this message.

Hope this helps.

MI
Matt Ion
Dec 01, 2016

If you're using Chrome, you can just right-click the image and search Google for it :)

U
Undisclosed #1
Dec 01, 2016
IPVMU Certified

Available here. $127

(2)
MI
Matt Ion
Dec 01, 2016

Found this really old post about these bits... unfortunately while both the links they have work, neither site seems to have this bit any more.

Avatar
Ryan Anderson
Dec 01, 2016

Bad Dog Bits, who normally has a booth at ISC West, has good bits. We have used the multi-purpose bits and the Rover Bits. They have been good, lifetime warranty too, if they break, they send you a new one (pay shipping of course)

(3)
Avatar
Craig Mc Cluskey
Jan 30, 2017

Most job sites in North America will use 2x4 studs, which, as the name implies, are 3.5" by 1.5".

In the 1970s, I lived in Sacramento, California. One company was doing some remodeling of some of the old buildings downtown. When they opened up an old wall, they found the studs were actually 2" by 4".

At that time, I was doing a lot of work with 2x4s; the ones I bought were 1-5/8" x 3-5/8", so the "make them smaller and charge the same price" has been going on for quite a while.

U
Undisclosed #1
Jan 31, 2017
IPVMU Certified

"make them smaller and charge the same price" has been going on for quite a while.

To be sure, they don't "make them smaller". 

When sawn they are fully 2" by 4", its the drying and planing process that reduces the size. 

Since the lumber is bought and sold at multiple stages in this process, it makes more sense to refer to the size when sawn instead of the actual size at any intermediate stages.

(1)