2x4 Butt Joint Marking Jigs

I'm always looking for ways to increase my productivity in woodworking projects by cutting out the time consuming "gotta be a better way" tasks. Marking out screw holes with a tape measure and pencil is time consuming and prone to the occasional mislocation. The 2 jigs I'll show you how to make will allow you to layout screw hole locations 40% faster over the old way. These jigs provide a consistent and repeatable method for your 2x4 joinery... providing you with that "better way."

These drill jigs are simple to make using small scrap wood you may have lying around, wood glue and a few tools. The impact on your productivity will be evident once you have these around your shop. The concept is definitely scalable to other dimensioned lumber.

In this instructable I will show you how to make 2 jigs and how to use them.

• Corner Butt Joint Marking Jig
• Mid Board Marking Jig with 2x4 centerline marking feature

Materials:

• 1/4" thick x 4.25" x 4.25" MDF or Plywood
• 3/4" thick x 4.25" x 2" Board or Plywood
• Wood Glue

Tools:

• Pencil and/or Fine tip marker
• Tape Measure
• Saw - I'll be using a handsaw and tablesaw (optional)
• Spring Clamps
• Combination Square
• Drill
• ø3/32 drill bit
• Countersink Bit or ø3/8 drill bit

Using a pencil, tape measure and straight edge. Mark out one each of the following pieces:

1/4" thick board

• 1.75" wide by 4.25" long (mid board jig)
• 2.25" wide by 4.25" long (corner jig)

3/4" thick board

• 3/4" wide by 1.75" wide (mid board jig)
• 3/4" wide by 3.5" long (corner jig)
• 3/4" wide by 2.25" long (corner jig)

Using the handsaw or tablesaw, cut the pieces out. Remember to double check which edge of the board is the waste side so you keep the pieces the correct length. I may have not done the whole check twice cut once in this step so I'm telling you.

Corner Board Jig

1. Apply a thin layer of glue to the 2.25" x 3/4" piece.
2. Align the 2.25" long edge to the 2.25" long edge of the 1/4" board.
3. Use a spring clamp to hold the piece in place while glue dries.
4. Apply a thin layer of glue to the 3.5" long piece.
5. Align the 3.5" long piece to the 4.25 long edge. The end of the piece will be up against an edge of the 2.25" long piece.
6. Use a square if needed to get close to an inside right angle.
7. Use a spring clamp to hold the piece in place while glue dries.

Mid Board Jig

1. Apply a thin layer of glue to the 1.75" x 3/4" piece.
2. Align the 1.75" long edge to the 1.75" long edge of the 1/4" board.
3. Use a spring clamp to hold the piece in place while glue dries.

Corner Board Jig

1. Measure and mark a line on the inside of the 1/4" thick board. The line should be 3/4" from the 3.5" long piece.
2. Mark on the line a distance of 1" from the 2.25" board.
3. Mark on the line a distance of 1.5" from the previous mark (or 2.5" from the end)

Mid Board Jig

1. Measure and mark a centerline on the inside of the 1/4" thick board. The line should extend from the 1.75" long board to the edge of the jig.
2. Mark on the line a distance of 1" from the 2.25" board.
3. Mark on the line a distance of 1.5" from the previous mark (or 2.5" from the end)

1. Using a ø3/32 bit, drill through holes at each of the 4 marks.
2. Using a countersink bit or ø3/8 drill bit, add a countersink to the outside surface of the jig (side opposite the glued on boards)
3. Countersink just enough to allow a pencil or marker to protrude all the way through the 1/4" thick board.

Mid Board Jig Only

1. Mark a centerline on the outside of the jig that lines up through the 2 holes.
2. Saw a groove just deep enough to go through the glued on board and 1/4" board. The cut should be 3/4" deep.

This groove will allow you to see a line on the backside of the jig for alignment purposes.

Mid Board Jig Only

1. On the side edge of the mid board jig, mark a line 3/4" from the glued on board.
2. Repeat the same line on the other side of the jig.
3. Using the handsaw, cut a shallow groove at the 2 lines just added.
4. Using a marker, fill in the groove to accentuate the feature.

This groove will be used as a centerline marking guide.

Corner Board Jig

1. Nest the long edge of the Corner Jig to the cut end of the 2x4 and the short edge along the top or bottom edge of the 2x4. The 1/4" board should be held up against the face (widest section) of the board.
2. Insert the tip of a pencil into each hole of the jig and move it around to mark the board.
3. Remove the jig and add cross hair marks or an X to highlight the holes just marked.

Mid Board Jig - Locating Holes

1. If lining up to a predefined line on the 2x4. Visually look down the groove on the top of the jig to position the jig centered over the mark.
2. Hold the short edge of the jig up tight to the top or bottom of the 2x4. The 1/4" board should be held up against the face (widest section) of the board.
3. Insert the tip of a pencil into each hole of the jig and move it around to mark the board.
4. Remove the jig and add cross hair marks or an X to highlight the holes just marked.

Mid Board Jig - Centerline Marking

1. Position the short edge of the jig up against the face of the board. The 1/4" board will be up against the top or bottom edge of the board.
2. The side of the 1/4" board with the shallow groove should be positioned at the center of the top or bottom edge of the board.
3. Insert the tip of the pencil into the shallow groove on the mid board jig.
4. Slide the jig towards the end of the board to cause the pencil to mark a centerline.
5. Use this centerline to aid in positioning the board when joining.