How to Make Double-Fold Bias Tape
Megan FowlerMaking your own double-fold bias tape lets you match your binding perfectly to your project, use a fun print that you already have, or turn smaller cuts of fabric into something genuinely useful.
It’s also much less mysterious than it looks.
You can make bias tape with a small bias tape maker, but you don’t need a special tool. An iron, a ruler, and a little patience will get you there too.
What Is Double-Fold Bias Tape?
Bias tape is made from fabric strips cut diagonally across the grain of the fabric, usually at a 45-degree angle. This direction has more stretch and flexibility than fabric cut with or across the grain, which allows the tape to bend around curves without bunching or puckering.
To make double-fold bias tape, the two long raw edges are first folded toward the center. This creates single-fold bias tape.
The entire strip is then folded in half one more time, enclosing the raw edges inside.
One detail that can cause some confusion is that the size printed on a bias tape maker refers to the width of the single-fold tape as it comes out of the tool. Once you fold that tape in half to make double-fold bias tape, the finished width will be approximately half of the maker size.
For example, a 25 mm or 1-inch bias tape maker creates 25 mm or 1-inch-wide single-fold tape. After it is folded in half, it creates approximately 12 mm or 1/2-inch-wide double-fold bias tape.
What You’ll Need
- Fabric
- Rotary cutter
- Acrylic ruler
- Cutting mat
- Iron and pressing surface
- Bias tape maker, optional
- Straight pin, stiletto, or seam ripper for feeding fabric through the maker
- Fabric marking tool, optional
What Is a Bias Tape Maker?
A bias tape maker is a small metal tool that folds the long raw edges of a fabric strip toward the center as you pull the fabric through it. You press the folds with your iron as the strip comes out, which makes it much faster and easier to create evenly folded tape.
It does not complete every fold for you. The tape that comes out of the tool is single-fold bias tape. To make double-fold bias tape, you’ll fold that strip in half one more time and press it again.
Bias tape makers are available individually or in sets with several different sizes. A set is useful if you plan to make tape for different types of projects, from narrow decorative details to wider binding and bunting. I have a generic set from Amazon that includes five color-coded makers in sizes from 6 mm to 25 mm, or approximately 1/4 inch to 1 inch.
This post contains an Amazon affiliate link. If you purchase through my link, I may earn a small commission at no additional cost to you. I only share products that I personally use and find helpful. As an Amazon Associate I earn from qualifying purchases.
See the bias tape maker set I use on Amazon.
You do not need a bias tape maker to follow this tutorial. I’ve included instructions for folding and pressing the tape by hand too. The tool simply makes the process faster and helps keep the folds more consistent, especially when you’re making a longer piece.
Bias Tape Maker Size Guide
The color coding below matches the bias tape maker set I use. Other manufacturers may use different colors, so check the measurement printed or stamped on your maker before cutting your fabric.
The measurement on the tool refers to the width of the single-fold tape that comes out of the maker. Your starting fabric strip should be approximately twice that width. After folding the tape in half again, the finished double-fold tape will be approximately half the width printed on the tool.
| Maker Color | Maker Size | Approximate Imperial Size | Cut Fabric Strips | Finished Double-Fold Width |
|---|---|---|---|---|
| Green | 6 mm | 1/4 inch | 12 mm or 1/2 inch | 3 mm or 1/8 inch |
| Orange | 9 mm | 3/8 inch | 18 mm or 3/4 inch | 4.5 mm or about 3/16 inch |
| Yellow | 12 mm | 1/2 inch | 24 to 25 mm or 1 inch | 6 mm or 1/4 inch |
| Red | 18 mm | About 3/4 inch | 36 mm or 1 1/2 inches | 9 mm or about 3/8 inch |
| Blue | 25 mm | 1 inch | 50 mm or 2 inches | 12 mm or 1/2 inch |
You may see very small differences between the exact metric conversion and the nearest convenient measurement on an imperial quilting ruler. That’s okay. For example, 18 mm is technically a little narrower than 3/4 inch, but a 3/4-inch strip is the practical cutting measurement for the orange maker.
Fabric thickness can also make a difference. If a strip is difficult to pull through your bias tape maker, trim a tiny amount from the width and test it again before cutting the rest of your fabric.
Choose the Right Bias Tape Size
Think about where the tape will be used before choosing your maker.
Smaller sizes work well for narrow stems, decorative details, and small projects. The 18 mm and 25 mm makers create wider tape that is easier to handle for binding, bunting, and other projects where the tape needs to enclose a fabric edge.
For many general sewing projects, the blue 25 mm or 1-inch maker is a useful option. It begins with a 50 mm or 2-inch fabric strip and creates double-fold tape that finishes at approximately 12 mm or 1/2 inch wide.
Cut the Fabric on the Bias
Lay your fabric flat on your cutting mat with one selvage edge running parallel to a horizontal line on the mat.
The true bias runs diagonally across the fabric at a 45-degree angle to the selvage.
Use the 45-degree marking on your acrylic ruler to establish the first diagonal cut. Trim away the edge to create a clean starting line.
From that line, cut parallel strips in the width needed for your bias tape maker. Refer to the size chart above before cutting. This is a particularly helpful moment to measure twice, because cutting six yards of strips at the wrong width is the kind of character-building exercise none of us requested.
Join the Bias Strips
Most projects require more bias tape than you can cut from one continuous strip, so the shorter strips will need to be joined.
Place two strips right sides together at a 90-degree angle, with the ends overlapping to form an L shape.
The corners of the strips should extend slightly past one another.
Sew diagonally across the overlapping section from one inside corner to the opposite inside corner. Before trimming, open the strips and make sure they form one long, straight strip instead of an accidental fabric boomerang.
Trim the seam allowance to approximately 1/4 inch or 6 mm.
Press the seam allowances open to reduce bulk.
Continue joining strips until you have the length needed for your project.
Make Bias Tape With a Bias Tape Maker
Cut one end of your fabric strip at an angle. The pointed end is easier to feed through the maker than a blunt, square end.
Insert the fabric into the wide end of the bias tape maker with the wrong side facing up.
Use a straight pin, stiletto, or the tip of a seam ripper to guide the fabric through the slot on the top of the tool. Pull the pointed end through the narrow opening until you have a few inches extending from the maker.
As the fabric comes through, the tool will fold both raw edges toward the center.
Hold the bias tape maker by its handle and slowly pull it away from the iron. Press the folded tape immediately as it comes out of the tool.
Work in short sections. Avoid stretching the fabric while pulling it through, since bias-cut fabric can easily become distorted.
Once the entire strip has been pressed, you have single-fold bias tape.
To turn it into double-fold bias tape, fold the strip in half lengthwise so the folded edges are enclosed inside.
For traditional double-fold tape, offset the edges very slightly so one side is just a bit wider than the other. When the narrower side is placed on the front of your project, the slightly wider back edge is easier to catch while stitching.
Press the tape in half along its entire length.
Make Bias Tape Without a Bias Tape Maker
A bias tape maker makes the folding process faster, but you can create the same folds using your iron.
Place the fabric strip wrong side up on your pressing surface.
Fold the strip in half lengthwise, matching the long raw edges. Press lightly to create a center crease, then open the strip again.
Fold one long raw edge toward the center crease and press it in place.
Fold the second long raw edge toward the center crease and press again. The two folded edges should meet at the center without overlapping.
You now have single-fold bias tape.
Fold the entire strip in half along the original center crease, enclosing both raw edges inside.
Offset one folded edge slightly if you would like the back of the tape to be a little wider than the front.
Press the final fold firmly.
An Easier Pressing Trick
When working without a maker, use a heat-safe ruler or a small piece of cardstock as a folding guide.
Mark half the original strip width on the guide. For a 2-inch or 50 mm strip, each raw edge will be folded in approximately 1/2 inch or 12 mm so the edges meet at the center.
Work a few inches at a time rather than trying to fold the entire strip before pressing. Bias fabric likes to wiggle, stretch, and generally act like it has somewhere else to be.
Tips for Neater Bias Tape
Use a lightweight quilting cotton for your first attempt. Heavier fabrics create more bulk and may not slide smoothly through smaller makers.
Press rather than dragging the iron back and forth. Dragging can stretch the bias strip and change its width.
Let each pressed section cool before moving it too much. This helps the folds hold their shape.
Keep the strip centered as it enters the bias tape maker. If one folded edge is noticeably wider than the other, stop and reposition the fabric before continuing.
Roll finished bias tape around an empty spool, a piece of cardboard, or a bias tape storage card. This keeps it from becoming a wrinkled fabric noodle at the bottom of your supply bin.
Straight-Grain Tape Versus Bias Tape
True bias tape is cut at a 45-degree angle and is the best choice when the tape needs to curve around rounded edges.
For straight projects, such as the top edge of a pocket or a string of bunting with straight-edged flags, you can sometimes cut the strips with the grain instead. The folding and pressing instructions are the same, but the finished tape will not have the same flexibility as true bias-cut tape.
When in doubt, cut it on the bias. It gives you more flexibility and works for both straight and curved edges.
Ready to Use Your Bias Tape
Once the final center fold has been pressed, your double-fold bias tape is ready to use.
Tuck the project edge between the folded layers, pin or clip the tape in place, and stitch close to the open folded edge. The raw edges of both the bias tape and the project will be enclosed inside for a clean finish.
And now you can make bias tape in any color or print you want, which is both wonderfully useful and a mildly dangerous new use for the fabric scraps you were definitely going to organize someday.
