Creating smooth curved seams with sewing machines involves a little extra work on the fabric. When sewn on Juki sewing machines like the Juki TL2010Q, curved seams and edges can stretch or bunch together when the seam is pressed open or any attempt is made to shape the seam to the curve of the pattern.
Thankfully, there is an easy way to deal with these curved “hills” and “valleys” after stitching so that seams come out perfect. Simply notch the hills and clip the valleys to let the fabric lay flat along the seams.
So What Are Hills and Valleys?
Hills and valleys refer to the shape of a curved seam area of the pattern piece, such as the cap of a sleeve or the neckline of a top or dress. When the fabric is joined to be seamed and then pressed, the allowance on a “hill” will bunch together in wrinkles. Conversely, when a "valley" is seamed, there is insufficient fabric to fit around the curve, so it pulls and will not lay flat no matter how much it is pressed.
It is always best to take a few minutes to remedy these issues in order to have seams and edges lay flat after stitching. By notching the convex hills and clipping the concave valleys, seams created on Juki sewing machines will lay smooth and flat. By using these two simple techniques, it is possible to get a professional-looking edge without unnecessary bulk or pull.
Notching Those Hills
Sleeve caps and other convex-shaped hills produce extra fabric at the seam when stitched. If left untouched, the fabric will bunch up at the stitches, leaving too much bulk underneath that will affect the fit of the garment. This is easily remedied by simply clipping triangular notches into the seam allowance to remove excess fabric along the seam line.
When the seam has been stitched with a machine like the Juki TL2010Q, the result is a smoothly finished seam or edge with no excess, bunched-up fabric.
Clipping Those Valleys
Fabric valleys can be handled in a very similar way. In these instances, when the seam has been stitched into the concave curve of the valley, the fabric may not have enough stretch to shape to the larger curve without pulling. If left alone, the resulting seam would ruin the lay of the curve, which would bunch up on the finished side.
When using sewing machines, correcting a valley after it is sewn is extremely easy and only involves cutting little slits in the allowance up to the point where the stitching has been done. This allows the allowance to stretch and open up so the seam edge will fit the curve that has been sewn. As with the technique for correcting hills, it allows sewists to easily create a flat and smooth seam that can be pressed flat.
Getting fabric to fit around curves can be challenging and could cause undesirable pulling or bulkiness if not properly handled. By using the simple techniques referenced above for correcting hills and valleys, anyone using sewing machines like the Juki TL2010Q can remedy these issues with just a few snips of their fabric scissors. Notched hills and clipped valleys are the perfect solutions for making curved seams and edges on Juki sewing machines!