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Back To The Basics: Seams Part Two

We’re going to wrap up our basic seams talk with Pressing and Understitching today, two often overlooked details that can make a world of difference.

Grading:  Grading your seam allowance is easy!  When you are working with thick fabrics or have more than 2 layers going on, the seam allowance can get bulky.  Let’s reduce a good portion of that bulk by trimming each layer to a different width so when you turn and press, there isn’t that weird bump running along the seam.

Notching/Clipping:   With your fabric laid flat in front of you, determine if your curve is concave or convex.  This will change how you cut into your seam allowance so everything lays flat.

  • If your curve is concave (curls inward or makes a “cave” <- that’s how I remember it), you will want to CLIP the seam allowance.  You should clip every 1/2″ to 1″ (1.2-2.5cm), depending on just how curvy your seam is.  Remember!  Don’t clip past your seam allowance!
  • If your curve is convex (pushes out, not in; I have no cute way of remembering that except it DOESN’T make a cave), make NOTCHES in your seam allowance.  Your notches will resemble little triangles cut out of the seam allowance.  Again, spread them out or push your notches closer together, depending on just how curvy your curve is.


Understitching:  Understitching is my baby, my secret weapon, my favorite of almost all techniques around.  Understitching is simply pressing your seam allowance towards your lining piece and sewing it to the lining just next to the actual seam.  When your project is turned and pressed, everything wants to roll in ever so slightly towards the inside so your lining doesn’t peek out.  For a lot of my patterns, it eliminates the need to topstitch certain areas, making the finished dress or top or whatnot look much cleaner and more finished (because haven’t we all made a great bodice only to mess up the topstitching somehow?).

Understiching example
See how the seam allowance is pressed towards the darker blue fabric and then sewn down?



Back to the Basics: Seams

Let’s talk about the most basic things in sewing:  Seams!

Seams are what keeps the whole project together (pun intended).  Today we’re going to investigate what makes a great seam that does its job without drawing attention to itself (unless a conspicuous seam is a design element).

Joining Seamlines:  Place your fabric edges together and pin.  You pins should be at a right angle to the edge of the fabric pointing in towards the body of the piece (heads towards the seam allowance).  This is something I TOTALLY do not follow, but I need to.  I admit it.  I can work on that.

Do NOT sew over your pins.  I have had the needle hit one and break and go flying right towards my eye, impaling my eyebrow.  Learn from me; do not end up with a sewing needle in your face.


Stitching:  When you start your seam, start the needle 1/2″ (1.3cm) from the end of your intended seam line and backstitch.  What’s backstitching?  It’s reversing your machine so it sews backwards for that little bit at the start (and end) of a seam so the stitches sort of “lock” up on themselves and don’t start to come undone as you are handling your project in later steps.  Some machines have a lock stitch option which eliminates the need to backstitch.  And if you forget?  No worries, you can always tie the ends of your thread at the beginning or end of your seam.

Reinforcing Corners:  Ooh, what about getting really nice corners?  You can either add a second layer of short, reinforcing stitches starting about 1″ (2.5cm) from the corner, and ending about 1″ (2.5cm) on the other side of the corner OR you can shorten your stitches as you approach the corner, sew with shorter stitches around the corner, then go back to your regular length for the rest of the seam.


Trimming:  Trimming should ONLY happen when you need to reduce bulk.  Corners will be trimmed across the point of the seam allowance close to the seam.  Then trim diagonally along both sides of the point to ease back into the normal seam allowance.