All Orange Lingerie bra sewing patterns are designed to use underwires and each style has a different neckline shape and center front height. This means the optimum underwire length varies by bra. Ordering a lot of bra underwires over the years I found that underwire lengths also vary, even when ordering the exact same wire. As you know, with bras, every ⅛” can make a difference!
For these reasons (plus a really small studio!), I maintain a supply of longer wires and I cut them to the size that I want using this method. I always make sure that I have ½” extra room in the casing channel. This extra space, often called “wire play”, allows the underwires to move when the bra is on the body so that they are not forced through the casing channel.
I realize not everyone likes to or wants to cut their underwires so in this tutorial, I will show you how to avoid cutting underwires for your bra. In exchange for the convenience, there is a cost! The cost is that you must alter the pattern and along with it, the style lines of the bra.
The first step is to measure the wire line of the bra. The underwire sits ⅛” away from the underwire casing attachment line. For a full frame bra, this distance is measured outside the cup to frame seam line. For a frameless bra, like the Fenway bra shown below, this distance is measured inside the cup to frame seam line. The endpoint of the underwire at the underarm is below where any trim is attached and the endpoint at the center front is below where the wire casing will be stitched closed.
Next you need to take the measurement of the length of your underwire and add ½” for wire play.
For this example, let’s say the pattern allows for 7½” for the underwires as measured above and your underwire plus the wire play amount measures 7⅞”. This means you need to add ⅜” to the wire line for your underwires to fit into the casing without requiring you to cut them to size.
To add to the wire line, you will increase the height of the center front of the pattern. This needs to happen in two places: the bridge and the upper cup.
Starting with the bridge, follow the existing wire line and add the necessary ⅜” from the seam line. Remember, all pattern alterations are made from the seam line!
For the upper cup, follow the upper cup to bridge seam line and add that same ⅜”. Then redraw the upper edge of your upper cup to correspond with the raised center front point.
While you have increased the coverage of the bra along the neckline, you do not have to cut any wires!
In case you were wondering, you can also make this adjustment in the opposite direction by decreasing the height of the bridge an upper cup, however, given the style lines of bras are carefully crafted for shaping and support, I don’t recommend making an adjustment up or down by more than ⅜”!