As we have seen in previous posts, bias tape helps us finish and polish many of our projects thanks to their adaptability. We can buy them ready to use or, with the help of the bias pre-bending machines, manufacture them ourselves.
Despite the appearance of dental instruments, the bias tape preparation machines are easy to use and most importantly very useful!
With the use of the machines, we can have the amount we want of bias tapes of different widths, with the same fabric of the garment that we are sewing. How many times have we been half-finished finishing a neckline because the time has come and the shops have closed?
Next, we are going to see the necessary materials to cut the strips on the bias, join them to make a strip with the desired length, and pre-fold them to be used in the seam.
- rotary cutter
- cutting base
- cutting rule
- bias machines
The traditional cutting shears can also be used to cut bias strips, but the cutter’s accuracy work is brilliant, and here millimeters are important. Those of you who are thinking of buying the rotary cutter and its base, this is one more point in your favor.
STEP 1 Prepare the fabric
- Stretch the fabric on the work table and locate the selvedges.
The selvages or edges of the fabric indicate the straight thread, the most stable direction of the fabric. The bias is diagonal to the straight thread and is the direction with the most elasticity. For this reason, the strips are cut with the bias direction, so that they are more flexible and we can adapt them to curved shapes such as collars or armholes.
- Make the first fold in the fabric.
- Make the second fold.
The two resulting diagonal lines with folded edges are on the bias.
STEP 2 Mark and cut the strips
In order to mark the width of the strips, we must first understand the meaning of the number that appears on each machine and how to apply it to calculate the width of the strip that we will have to cut.
In the tutorial, we have used the machine with number 18. This means that the final bias tape with pre-folded margins, as we would buy it already made, will measure 1.8 cm.
To get the necessary strip width we will multiply this number by two. In this way, we will cut 3.6 cm wide strips to insert into the machine and get a 1.8 cm wide bias tape.
- Parallel to the folded edge, mark the lines corresponding to the width of the strips with a ruler.
As you can see, the first strip is half as wide as the rest because the fabric is folded.
- Cut the strips accurately and calmly.
Now we have a bunch of bias cut strips with different lengths, ready to be tied together into one long continuous tape.
In the image, we can see the different drawings of the moles depending on the direction of the thread. If you also stretch both vertically, you can check the elasticity of the strip cut on the bias.
STEP 3 Sew continuous tape
- Place the ends of the tapes face to face, as shown in the image.
- Secure with pins.
- Make a stitching ensuring the beginning and end of the seam.
It is very useful when sewing diagonals, pulling the upper needle thread, and using the thread as a guide to know where we have to sew.
- Cut and leave a margin of 0.5 cm.
- Open the seam allowances with the tip of the iron.
Perfect bias stripe binding! On the bias strips, the joint has to be a bias seam as well, but the balsamic effects of the tape fade away.
It is important to note that the wider the fabric used to remove the strips, the longer they will be and the more spaced apart the splices will be.
STEP 4 Pre-fold with the machine
- Insert the bias tape with the wrong side of the fabric facing us.
- Stretch the fabric on the narrow side, and see how the margins are folded!
In order for the margins to come out balanced, it is important to watch the “feeding” of the bias strip from the back. At first, between pulling the tab on the machine and ironing, it may happen that the ribbon twists a little and one margin is wider than the other.
- Pursue with the tip of the iron the tape that comes out of the machine.
Once the trick is taken, using the machine is a vice! You can find that there are fabrics that do not stay as ironed as others, or that require an extra few millimeters in the cut of the strip width due to the thickness of the fabric.
With very stable fabrics it is almost pure mathematics, but with the rest, you always have to do some tests before cutting strips and strips to a certain width.
Practice a lot with these magic gadgets, because in the Summer with BestSewingGuide Sew we are going to use very narrow bias tape.