One Piece Underarm Gusset Sewing Tutorial
How to insert a one piece underarm gusset into a kimono style sleeve.
This is the easiest way and provides neat, professional results. Follow the diagrams and photographs, read the text, and then watch the video.
The construction of the underarm gusset from the kimono-style bodice, often used throughout the 1950s, is often thought of as difficult and complicated, but it’s really not as hard as it looks.
Practice first on a mock-up or two. The fit of the sleeve is much better with a diamond gusset, so it’s definitely worth learning how to fit them.
This is showing typical placement of a one piece underarm gusset.
The four sides may be all different lengths, its important to match them correctly and cut on the correct bias.
The gusset gives extra ease of movement in a kimono style sleeve, very common throughout the 1950s.
For the many folk who hate sewing sleeves into armholes kimono sleeve dresses are fast and easy to sew.
The kimono style sleeve is all one piece with the front and back pieces, giving a simple shoulder seam and under arm seam.
There may be a dart in the back sleeve section to control shape.
Always start from the neck edges, basting or pin to check that the back and front sleeve match at the cuff.
The method to sew the facings to the slit marked on pattern is shown below in the diagrams.
On the pattern there will be a slash marking at the curve of the underarm. Mark this line on the right side of each bodice section, front and back and left and right sides.
Cut rectangle of fabric to face this slash, approximately 2 inches wide and 1 inch longer than the marking. Pin or baste facing strip along slash marking, right sides together. Stitch, beginning at edge 4mm (1/8) inch from slash marking and taper to the point. Take one extra stitch across point and stitch down other side.
Now cut the line very carefully to stitching at the point.
Showing facing turned to inside. repeat for other bodice pieces so you have 2 fronts and 2 backs.
Press & lightly starch.
Align the front and back bodice right sides together.
Pin and stitch underarm seams of bodice and sleeve, matching any notches and faced slit edges.
Press side seam and under arm seam open. Tum bodice to right side.
This method avoids weak corners and fraying stitches and all your garments look smart and professional.
Showing underarm and bodice side seam sewn, and the facings sewn and turned under the slit that is marked on the pattern.
The dress is ready for the gusset to be sewn in.
This method is easy because the gusset is placed under the open hole, right side facing towards you and you align to match the correct sides of gusset to bodice and sleeve sections..
Pin, baste and the topstitch the gusset in place close to the edge of the open hole edges.
Thats it finished. neat and no stress!
Showing the finished gussets and the shape of the full kimono sleeve.
The shape of a one piece underarm gusset is usually a diamond or kite shape.
Note that on some Vintage patterns all four sides may be slightly different lengths and will need marking / notching so you position the gusset the correct way around in the garment.
Edges are best stay stitched because they are cut on the bias.
Once you have practiced inserting a few you can choose how to neaten the raw edges. Pinking, narrow hem, rolled hem or binding. The weight and feel of the fabric determines how to finish the edges.
This is the paper pattern for the kimono sleeve in the video below. All 4 sides are slightly different lengths.
The inside darkest printed line is the actual size of the hole that the gusset fits into. the middle line is my fold line. The outer dotted line is cut lime for fabric.
Cut a cardboard piece to fit the middle printed line. This pattern gets used alot so having a stiff template makes ironing the gusset edges quick and accurate.
Fold and glue the paper pattern to your stiff car liner as shown.
This just makes it simple and easy to press the gusset.
As you notice this pattern is in French, take care to lay the template onto the fabric aligning the fabric bias with the bias line.
Cut out a piece of fabric larger than the template, it doesn´t need to be exact as will be trimmed after pressing.
Now starch the piece with spray starch until its firm. Don’t skip this bit!
Top tip: Use 25% cheap vodka to water for a good cheap spray starch that won´t stain darker fabrics.
The video shows inserting a white gusset into a black garment just to make it easier for you to see.
The template is marked with water soluble pen here to shw you need to mark one corner so you can keep it correct way up to insert correctly.
Now you can Fold the fabric edges over the template and press. opposite sides then trim, then the other two sides same and trim.
With experience you will have the fabric right side upwards and the edges are ironed so when sewn in place the pinked raw edges are concealed on the inside of the seam. The inside of the garment is as neat as the right side. Dont´t stress for first one if its easier to sew with pinked edges showing on inside of garment.
Use baking parchment or a linen pressing cloth between iron and template to prevent ink / toner transfer from your template. It will last for many garments.
Follow the video for the next part, inserting into the prepared gusset hole.