Woodworking Screws: Types, how-to, and tips


Woodworking screws are tools that are needed in many applications but the complexity of them are often overlooked. Honestly, they are not that complex, but the large variety of them can overwhelm a beginner at the store.

In this article, I will go over the common types of screws used in woodworking projects, how to pick the correct screw size, how to insert screws, and much more.

Directory

Types of woodworking screws

TypeUse
Wood ScrewsGeneral wood screw to attach wood to wood
Pocket hole screwsCreate pocket hole joinery
Machine screwsAttach metal to wood
Carriage boltsSecure traditional wood joinery

Wood screws

Wood screws are used to attach wood to wood. The best use of them is to attach the face grain of the wood together.

Wood screws are not ideal for attaching wood at a right angle. This is because the screw will go through the face grain of one wood piece and the end grain on another wood piece.

With the way wood works, you never want to screw into the end grain, because the grain will separate and loosen the joint.

To learn more about how wood works and pocket hole screws, check out my article “What is a pocket hole joint”.

Pocket hole screws

Pocket hole screws are the most common types of screws that I use for my projects.

They have larger heads that will not sink into the wood. This so the screw will not go to far and stick out on the other side.

Pocket hole screws are ideal for creating right angle joints because the nail is diagonal and not straight on with the end grain of the wood.

To learn more about pocket hole screws and how to use them, then you should check out my article “What is a pocket hole joint”.

Machine screws

Machine screws are often used to secure metal to wood.

As example of this is using machine screws and hex bolts to secure a benchtop vise to wood.

Machine screws have a flat tip and cannot drill into to wood. So you will need to make a pilot hole and insert the screw.

Carriage bolts

Carriage bolts are commonly used in woodworking for knockdown joinery.

Carriage bolts can be used to secure mortise and tenon joints by drilling the bolt through the mortise wood and tenon and securing the nut on the tenon.

Woodworking screw drive types

Screw drives are the top of the screw that the drill bit inserts into. There are three main types of screw drive types in woodworking that include Phillips head, flat-head, and torx drives.

3 Woodworking screw drive types

Phillips headFlat-headTorx
ShapeCross shapedSingle blageStar shaped
TorqueLowMediumHigh
CenteringHighMediumHigh
Cost$$$$

Phillips head

Phillips head screws are crossed shaped and used with Phillips head screw drivers.

Phillips head screws have high control and easy centering, but lower torque. Phillips head screws are efficient for joints that do not require great amounts of torque, like joining wood along the face grain.

Flat-head

Flat head screws have a single blage and are used with flat head screw drivers.

Flat-head screws have more torque than phillips head screws because they are not as prone to stripping.

Flat-head screws are not as easy to center and the screw driver can easily slip out from the sides.

Torx

Torx screws are star shaped and require the corresponding bit.

These screws are provide the most torque and are easy to center. The downside to torx screws are that they are considerably more expensive.

It is common practice to only use torx screws when you need high torque and precision.

How to insert a wood screw

Drilling a wood screw is an easy task to master. You will need the following materials and to follow these steps

Materials:

  • Drill bit
  • Drill or screw driver
  • Screws
  • Pencil or pen

Steps:

  1. Mark the location
  2. Drill a pilot hole
  3. Position the screw
  4. Drill the screw

Step 1: Mark the location

First, you will mark the location where you want to put the screw. Marking the location is helpful to ensure that the screw stays on track.

Step 2: Drill a pilot hole

Next, drill a pilot hole using a drill and a drill bit that is smaller than the screw.

Pilot holes are very helpful in preventing wood splitting and for drilling into harder woods.

I use the eyeball method and look at the threads of both side by side.

Tip: If you are having trouble determining if the drill bit is smaller than the screw, then go to a smaller drill size.

Once you have the correct drill size, drill a hole at the marked location.

Step 3: Position screw

Now, position the screw in the drilled pilot hole or at the marked location. The drilled hole should be smaller than the screw and the screw should not be able to slip into the hole.

Step 4: Drill screw

Using a drill or screwdriver, rotate the screw clockwise to drill it into the hole.

Once the screw is tight, do not overscrew it. Over screwing a screw can loosen the wood at the tip and cause the screw to become loose.

How to countersink wood screws

Countersinking wood screws is done when you want the screw head to either be flushed with or under the wood surface.

To counter sink wood screws, you will need the following materials

Materials:

  • Drill bit
  • Drill or screw driver
  • Screws
  • Pencil or pen
  • Countersink bit
  • Chuck (for countersinks with drill bits attached)

Type of countersink bit

There are two main types of countersink bits. You have countersink bits that are attached to drill bits and those that are drilled separately.

Countersink bits that are attached to drill bits are nice because they allow you to adjust the amount of drill bit that will be drilled before countersinking.

Determine countersink size

You want a countersink size that is the same size to match the radius of the screw head.

Determining the countersink size can be easily done by the eyeball method where you put the screw head in front of the countersink bit and see if you can barely see the countersink around the screw (picture).

Countersinks attached to drill bit

In order to countersink screws with the countersinks that are attached to drill bits you will need to follow these two steps.

Step 2: Attach countersink to drill bit

After marking the wood in step 1 of “How to insert a wood screw”, you will attach the countersink to the drill bit.

To attach the countersink to the drill bit, you will need to insert the drill bit into the countersink and tighten the bit using a chuck.

Step 2A: Drill drill bit into wood

Now you will drill the pilot hole that will simultaneously create the countersink.

Individual countersinks

To countersink screws with individual countersinks, you will need to follow this step.

Step 2A: Drill countersink hole

After drilling a pilot hole in step 2 of “How to insert a wood screw”, you will drill a countersink hole in the same location.

For wood screws, you do not need to countersink very deep. You just need to go the depth of the screw head thickness.

For screws with larger heads, like bolts, you will need to countersink considerably deeper, depending on the screw head size.

How to hide/cover screws in wood

You can hide wood screws by countersinking the screw so that the head is under the wood surface.

Once the screw is under the wood surface, you can cover it using the following methods

  1. Plugs
  2. Wood filler
  3. Saw dust

Method 1: Plugs

You can use wooden plugs to insert into the countersink hole to hide wood screws.

Step 1: Secure Plug to wood

To use wooden plugs, you will get the correct size hole for the countersink bit.

Next, you will use wood glue to secure the plug to the wood. Let the glue fully dry before moving to the next step.

Step 2: Flush plug with wood

Once the plug is dried, use a hand saw to cut off the excess material from the plug

Step 4: Sand and finish

Sand to perfectly flush the plug and remove any excess wood glue. Afterwards finish with stain or paint.

Method 2: Wood filler

Wood filler is an easy to use and effective in hiding wood screws.

Step 1: Apply wood filler over countersinked hole

First, you want to use wood filler paste and apply it over the countersink. Apply enough paste to fully cover the hole. Allow the recommended time to dry.

Step 2: Sand filler to an even surface

Once the wood filler is dried, sand the filler down to the wood surface to get an even, clean result.

Purchase wood filler: Minwax High Performance Wood Filler 12-oz

This is the wood filler that I like to use. It is very affordable, durable, and gets the job done.

Method 3: Saw dust

If you do not have wood filler, then you can use fine saw dust to cover countersinked holes. Fine saw dust is essential to use because larger saw shaving can fall off over time and be visible.

Step 1: Apply wood glue and fine saw dust to countersinked hole

First, you will add wood glue to the hole and then the fine saw dust. Then you will add a little more wood glue and let it dry.

You want the glue and dust to mix as much as possible. You can manually mix it by using mechanical pencil led or another thin tool.

Step 2: Lightly sand to an even surface

Once the wood glue is completely dried, lightly sand the surface to get an even, clean result.

Conclusion

In this article, we learned about the different types of woodworking screws and screw drive types. We then learned how to insert a wood screw, countersink wood screws, and hide/cover them

Thank you so much for taking the time to read this article and I wish you luck on your woodworking journeys!

Rachel

My name is Rachel Blanding and I am a woodworker. I started woodworking at the beginning of the COVID-19 pandemic. I mainly create and refurbish furniture and create art. In this site I will share with you the knowledge I have gained over the years, and what worked for me and what didn't.

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