Welcome back! Today, we tackle the sleeves. There are a couple of fiddly parts, but overall, they are pretty straightforward, especially considering you’ve probably inserted sleeves before. Let’s jump in!
Placing right sides together, sew the underarm seams of the upper and lower sleeves. Press seam allowances toward the upper sleeve, then finish and topstitch the seam.
Run three lines of basting stitches around the sleeve cap (between the front notch and the back sleeve seam) at 1/4”, 3/8” and 1/2” seam allowances. Leave long thread tails on each end to make gathering easy later.
On the remaining raw edge of the lower sleeve, turn under the raw edge of the lower extended edge under 1/4”, then another 3/8”. Topstitch fold in place at 1/4”.
On the remaining raw edge of the upper sleeve, clip 5/8” into the seam allowance at the notch. Below the clip, turn raw edge under 1/4”, then another 1/2”, then topstitch at 1/8” and 3/8”. Stop both lines of topstitching at the same place and backstitch twice. We will cover this in a moment with a bar tack.
Placing right sides of upper and lower sleeves together, sew from the sleeve cap to the folded placket of the upper sleeve (make sure the sleeve lines up across the bottom!), backstitching on each end. I do not recommend trying to flat fell this seam, so simply finish the raw edge, press toward the upper sleeve, then topstitch at 1/8” and 3/8”. Take special care to end these lines of topstitching just over the placket’s topstitching and backstitch twice. (You will need to topstitch the sleeve inside out, starting from the sleeve cap, as shown above.)
Topstitching this seam is pretty fiddly. You will have to sew into a tube, but it IS doable–just when you think you have run out of room, you reach the placket topstitching. Just go slowly here, readjusting every few stitches, and you will be fine!
Sew a bar tack horizontally across where the two sets of topstitching meet (I also recommend doing this with the sleeve inside out, but from the bottom of the sleeve opening). If your machine is having trouble sewing a bar tack with topstitching thread, switch to matching regular thread.
And you’re done with a sleeve! Finish up your second sleeve, and set them aside. We’ll attach the cuffs and waistband tomorrow (which are sewn the same way as the collar)!