Grading, Trimming, Clipping and Notching

Grading, Trimming, Clipping and Notching 
What are they, when and why do we use these techniques?

Whether you’re working on bulky fabric like a denim or wool jacket, or a lighter fabric such as a cotton dress, silk blouse, or underwear—the technique of grading seams is the same. These small techniques will make a big difference to your finished garment, helping smooth the seams and giving a professional finish to every seam! Carol Bentley explains how….…

Grading seams
Grading is a technique usually used when a seam has multiple layers, often in areas like a collar, waistband, or cuffs. It reduces the bulk to ensure a smooth, professional finish, especially on enclosed seams. 

It can also be referred to as ‘layering’ because each layer of fabric is reduced in increasing amounts, starting with the fabric closest to the right side of the garment and increasing the amounts cut away until the fabric farthest from the right side is the shortest. This creates a less bulky and smooth appearance from the right side of the garment.

However, sometimes the side of the seam closest to the outside of the garment will change, such as with the lapel of a blazer or jacket, as the centre front of the jacket (where the fastenings are) will have the outside of the seam in one direction, but when the lapel folds over to the outside forming the collar of the jacket what was on the inside will suddenly be on the outside, in this case, one can switch the grading to suit!

Grading is usually performed in very small increments of ⅛in and although it’s easy enough to do this with standard scissors, I prefer to use special scissors, which are designed for this purpose. Duck-billed scissors have one normal scissor blade, but the other blade has a semi-circular blade designed to hold the lower layers down enabling the upper to be cut away more easily minimising the risk of cutting the lower layers (we’ve all done it!).

Trimming seams
Trimming sounds similar but is slightly different. This is where all the seam allowances of the layers would be trimmed shorter by the same amount. This is what we would do when pattern instructions say to trim the seam allowance to say 1cm.

For trimming seams, I usually just use my standard dressmaking scissors unless working on a very small curve, at which time I would use my stork embroidery scissors or snips. By clipping into the seam allowance close to the stitching line, you’ll release the tension and find that pressing your seam out to the right side is now easier!

Clipping Curves
For concave seams – you’ll need to clip the seam allowances.  This type of seam is found on a neckline and look these highly visible areas must look perfectly flat when turned to the right side. 

Notching Curves
Notching is applied to a convex seam in areas that require shaping like bust princess seams and scalloped hemlines. If you try and turn a convex seam without notching, the excess seam allowance bunches. Snipping little triangles from the seam allowance every ½in close to the stitching line allows the seam allowance to spread and reduce the unwanted fabric here.