Sewing Tank Tops: Mastering Armhole Techniques

Tank tops are a versatile wardrobe staple, but sometimes you may want to adjust the armholes for a more personalised fit. This could be to create a more relaxed silhouette, increase airflow, or simply to fix gaping armholes. In this article, we'll guide you through the process of altering tank top armholes, covering everything from preparing your fabric to trying on the finished product. So, grab your sewing kit and let's get started!

Finishing the raw edges

Once you have cut along the new seam line and removed the excess fabric, it's time to finish the raw edges to prevent fraying. There are a few different methods you can use:

• Serging or Zigzag Stitch: Use a serger to finish the raw edges, or alternatively, you can use a zigzag stitch. This will secure the fabric and prevent it from fraying.
• Fabric Fray Check: If you don't have a serger or prefer not to use a zigzag stitch, you can apply a fabric fray check solution to the raw edges. This will help prevent fraying and create a clean finish.
• Fold and Stitch: Cut a strip of fabric about 1" wide and long enough to cover the raw edge. Fold this strip in half lengthwise, wrong sides together, and press it. Then, line up the raw edge of the fabric with the raw edge of the armhole, right sides together. Sew a narrow seam, and press the strip towards the inside of the tank top. Finally, fold the raw edge of the strip inward and stitch it in place, neatly hiding all the raw edges. This method creates a clean finish and adds a nice detail to your tank top.

Additional Tips:

• When using the fold-and-stitch method, you can leave a little overhang on the strip to cover up any raw edges from creating an opening, such as a button loop, at the back of the tank top.
• Always ensure that your stitches are secure and that there is no puckering along the seams.
• Press the seams with an iron to set them in place and achieve a polished look.

Creating a new seam line

Marking the New Seam Line:

Use the measurements you previously took to mark the desired increase in armhole size. This can be done with fabric chalk or pins. Ensure that the adjustments are symmetrical on both sides of the garment to maintain a balanced appearance. When marking the new seam line, gradually curve it towards the bottom of the armhole, seamlessly blending it with the existing shape. This step is crucial for a natural and flattering transition between the original seam and the new one.

Cutting Along the New Seam Line:

Carefully cut along the marked path, removing the excess fabric. Take your time and follow the marked measurements to ensure precision. Cutting along the new seam line requires accuracy to achieve the intended fit.

Finishing the Raw Edges:

To prevent the newly cut fabric from fraying, it is essential to finish the raw edges. This step contributes to a polished and durable finish for your garment. You can use a serger, a zigzag stitch, or apply a fabric fray check to secure the edges.

Sewing the New Seam:

Pin the fabric along the new seam line to hold it in place. Using a straight or zigzag stitch, sew along the pinned area, ensuring that the stitches are secure and even. A zigzag stitch provides added stretch, which can be beneficial for the armhole area. Double-check that there is no puckering or bunching along the seam.

Trying On and Adjusting:

After sewing the new seam, try on the tank top to evaluate the fit. This step allows you to make any necessary adjustments to ensure comfort and style preferences are met. It is important to try on the garment to ensure the desired outcome.

Measuring and marking

Before you start sewing, it's important to measure and mark your tank top to ensure a precise fit. Here's a step-by-step guide on measuring and marking your tank top before sewing the armholes:

• Try on the Tank Top: Put on the tank top and assess the fit of the armholes. Determine how much larger or smaller you want the armholes to be. If they are too big, pinch the fabric under the armholes to estimate the amount that needs to be taken in. If you're creating a new armhole, mark the desired position with tailor's chalk or a disappearing fabric pen.
• Transfer Marks: If you're altering the armholes, transfer the marks you made on one side of the armhole to the other side to ensure symmetry. For new armholes, you can use an existing tank top as a template by laying it on top of your new fabric and tracing the armholes.
• Use a Measuring Tape: If you're taking in the armholes, use a measuring tape to accurately measure the desired adjustment. This will help you achieve a precise fit.
• Mark the Adjustments: Use fabric chalk or pins to mark the desired increase or decrease in the armhole size. Ensure that your markings are symmetrical on both sides for a balanced and even look.
• Create a Master Pattern: Consider creating a master pattern by cutting your first draft on a piece of fabric you don't mind messing up. This way, you can perfect the shape and fit before cutting into your actual tank top fabric.
• Consider Darts: Darts are folds in the fabric that add shape around curvy areas, such as the bust. You can create darts by making a fold about two inches down from the armpit and tapering it towards the side seam. Sew the darts in place and trim any excess fabric.

Remember to take your time during the measuring and marking process to ensure an accurate fit. Once you're happy with your markings, you can proceed to the next steps of cutting and sewing your tank top armholes.

Attaching bias binding

Step 1: Prepare the Binding Strips

Cut strips of stretchy knit fabric for the binding. The strips should be 2 inches wide and cut on the stretch of the fabric. Measure the armhole, starting at the shoulder seam and going down to the side seam. Double that measurement and then subtract 1 inch to get the length for the binding strips. Cut the strips to this length.

Step 2: Sew the Binding Strips Together

Place the strips right sides together and sew the short ends together using a ¼ to 3/8 inch seam allowance. This will form a ring. Repeat this process for both strips. Fold the rings in half to find the halfway point and mark it with a pin.

Step 3: Attach the Binding to the Tank Top

With the tank top wrong side out, line up the binding seam with the side seam and pin it in place. Also, line up and pin the halfway points of the binding and the armhole. The binding will be shorter than the armhole, so you will need to stretch it slightly as you sew. Sew the binding to the tank top using a 3/8 inch seam allowance and a regular straight stitch. Start at the underarm seam and sew all the way around.

Step 4: Fold and Press the Binding

Fold the binding over to the wrong side of the fabric, with the seam facing outward and toward the binding. Pin or clip it in place all the way around, making sure the seam is enclosed within the binding. Press the binding with an iron to set it in place.

Step 5: Stitch the Binding in Place

On the top side of the fabric, stitch in the ditch where the shirt meets the binding. Start sewing at the crevice where the two meet, easing and stretching the fabric slightly as you go. Backstitch at the beginning and end of the seam. Trim any excess fabric close to the seam, being careful not to cut the fabric underneath.

Tips:

• You can use stretchy knit fabric strips from upcycled clothing to add character to your tank top.
• It is better to have too much fabric than not enough when attaching the binding.
• If you are using store-bought bias tape, choose a similar color to your tank top fabric.

Adjusting the armholes

Marking the Armhole

Try on the tank top and determine the desired position of the new underarm. Use tailor's chalk or a disappearing fabric pen to mark the new underarm position at the side seam. Transfer this mark to the other armhole to ensure symmetry. Make additional marks at the front and back of each armhole to guide your adjustments.

Unpicking the Binding

If your tank top has bias binding at the armholes, use a seam ripper or a sharp razor blade to carefully unpick the stitching. Start about 1/2" above your mid-armhole markings to give yourself room to manoeuvre. If the binding has been backstitched, remove the backstitching about 1/2" past your starting point so you can get your needle above the original stitching.

Cutting an Inset Piece

As you are lowering the armhole, you will need to extend the bias tape. Measure the width of the original bias binding and determine the length of your extension piece by adding the amount you are lowering the armhole, plus an additional 1" for seam allowance (1/2" on each side). Cut a new piece of bias binding from similar fabric, or use store-bought bias tape in a matching colour and width.

Attaching the Inset Piece

Attach the new bias binding piece to the original piece by placing them right sides together at a 90-degree angle. Sew a diagonal line of stitching to connect the two pieces. Repeat on the other end and press the seam allowances open. Trim any excess fabric.

Re-attaching the Bias Binding

Follow the standard steps for attaching bias binding. You can draw the new stitch line with tailor's chalk to guide your stitching. Re-stitch the bias binding, following a natural curve towards the lowered mark.

Trimming and Finishing

Carefully trim the excess fabric from the old armhole, leaving about 1/4" of the stitch you just made. Backstitch, press, turn, and topstitch as usual when attaching bias binding. Use thread that matches the original topstitch thread for a clean finish.

Tips and Troubleshooting:

• It is recommended to try on the tank top and mark the desired adjustments before cutting or sewing. This will help you visualise the final result and make any necessary adjustments.
• When unpicking stitches, be cautious to avoid damaging the fabric.
• Choose a thread colour that closely matches your tank top fabric for a seamless finish.
• Take your time and work precisely to avoid errors.

Frequently asked questions