Hello dears! After the enthusiastic response to my flex-sleeve blouse, I realized I had better get up a tutorial quick, before something else takes its place and causes me to put it on the back burner. So, do you want to make a blouse that won’t come untucked? Well then let’s get started, and make a flex-sleeve adjustment!
First off, you will need a basic blouse or bodice pattern (depending on what garment you want to make the adjustment to. This will work on anything with set-in sleeves). Also, measure how high you are comfortable with your armhole sitting. Do this by sliding a horizontal ruler up under your armpit till it is at a comfortably high position, and then measure from your shoulder to this ruler using a second, vertical, ruler. If you need a picture, let me know and I will add one. Mark this number down, because we will need it in the next step.
Now we are going to take the same measurement that we just did on ourselves, only this time we are measuring the pattern. Hopefully this will help you visualize how to take the measurement I mentioned above. Place your front and back bodice pieces so that the center front and center back are parallel, and the corners of the armscye at the side seam meet. Place a horizontal guide ruler so that the top of it sits at the base of the armscye. Now, using a vertical ruler, measure from the guide ruler up to the shoulder seam of the bodice. Compare this measurement with the one you took on yourself. If there is a good 1.5-2 inch difference, then you are good to go with making a flex-sleeve adjustment! If not, well then, you are going to have to use another method that I don’t have the time (or the knowledge) to go into here.
Now, take your bodice front and back pieces and align the side seams on the seam line, making sure the waistline and the armscye match perfectly. At this point, I would recommend working without seam allowances, and then adding them back in after making the flex-sleeve adjustment.
Zooming in a little here… Take a spare piece of paper and place it under your pattern pieces. If you need to, you can lightly tape down your pattern pieces so they don’t shift around. Measure up 1.5-2 inches (depending on what the difference between your armhole depth and the armhole depth on your current pattern is). Mark a dot.
Draw a vertical line from the underarm seam up to the dot. At a right angle to this line, draw a horizontal line, starting at the dot, across to each side of the armscye. Cut apart the paper guide along the lines just drawn, making sure to keep the front bodice and front guide together, ditto for the back pieces. Using a large sheet of tracing paper, trace off your new front and back pattern pieces with your flex-sleeve guides, marking the original armscye, and adding back in the seam allowance along all seam-lines. Make sure to add seam allowance to the top of your new squared armscye as well.
Now, mark your paper guides, on both sides, which is for the front, and which is for the back. Flip them over. Now prepare your sleeve pattern, removing or disregarding the seam allowance at this point.
Take your flipped front guide piece and place it to correspond with the front side of your sleeve armscye. Do the same for the back. It isn’t so important here that the curves match up perfectly, as it is to make sure that the underarm seam corners of your guides don’t extend beyond the current underarm seam-line. Also, make sure they aren’t leaning in too far away from the current underarm seam-line. This is the mistake that I made in my first attempt at this adjustment which led to the bubbly underarm seam on the sleeve.
Lightly tape down your sleeve pattern piece and the flex-sleeve guides to the surface you are working on. Place a sheet of tracing paper (I like Swedish Tracing Paper personally) over your whole pattern. Using a ruler, draw new underarm seam-lines to connect the corners of your flex-sleeve guides with the corners at the hem of the sleeve.
Trace off the rest of your sleeve, adding back in the seam allowance, as well as marking the original armscye (should you need to make adjustments).
And there you have it! You have a new flex-sleeve adjusted pattern! Basically what we have done here is to cut the armscye so that it is no longer circularly shaped, but instead it has a square line to it. This square line is caused by the cut on “gusset”, which is what allows for the increased mobility. Now go sew up your blouse (or dress) without boundaries!
Anything not quite clear? Need me to explain something better? Comment!
If you make a blouse with the Flex-Sleeve adjustment I would love to see it! If you share it on social media, tag it with #blousewithoutboundaries or #flexsleeveadjustment.
Brigid, the Middle Sister and Singer