Wondering how to adjust a raglan sleeve sewing pattern for a larger bust? If you're used to making a full bust adjustment (AKA "FBA") on your sewing patterns, but don't know how to go about it on a garment that has raglan seams attaching the sleeves to the bodice, then this tutorial is for you.
First up, how do you know if you need to make a full bust adjustment?
This sewing pattern alteration is often required if you have a fuller bust. If you buy or sew clothes to fit the fullest part of your bust, you'll often find that there is excess fabric pooling at your shoulders and upper chest, because this part of you is smaller in comparison.
However, when it comes to deliberately oversized tops with deep raglan sleeves - such as the Drew sweatshirt sewing pattern, which I'll be demonstrating on here - these garments have a lot of intentional design ease around this area anyway. So in most cases you won't actually need to make a full bust adjustment - you can select your size based on your high bust measurement and simply make that size without any bust alterations.
But, if your full bust is 5 or more pattern sizes bigger than your high bust, then I would recommend making a full bust adjustment.
How much do I have to add to the bust?
I'm going to briefly cover how you would work out how much to add to the bust in the adjustment, but do remember this is just a rough framework rather than an exact science.
Measure your high bust (your upper chest, just under your armpits). If you're making sizes 1-6 (UK 6-16) in our patterns, add 5cm (2in). If you're making sizes 7-15 (UK 18-34) in our patterns, add 10cm (4in). If you're making a pattern by another designer, you may need to add a different amount. Choose the pattern size with that full bust measurement – this is the size you’ll do your bust adjustment on.
Now measure your full bust (fullest part, around the nipples) and compare it to the bust measurement on the pattern size you just selected. If your full bust is 5cm (2in) bigger than the pattern, you’ll be adding 5cm (2in) to the pattern; if it’s 7.5cm (3in) bigger, you’ll be adding 7.5cm (3in) and so on. For a garment in stretch knit fabrics (such as Drew), reduce this amount by 10-25% depending on how much stretch is in your fabric.
What you'll need:
- Your front bodice pattern piece (trace this off so you're not chopping up your original pattern)
- A pen or pencil
- A ruler (or pattern master tool if you have one)
- Scissors
- Tape or a glue stick
- A piece of paper slightly bigger than your pattern piece
Now you've got those ready, let's get into it!
How to make a full bust adjustment on a sewing pattern with raglan sleeves
Stand in front of a mirror and hold the front bodice pattern up to your body so the centre front line is running down the centre of your torso, and the neckline is sitting roughly where the finished neckline will be, remembering to account for the seam allowance - bear in mind that if your pattern has a neckband, like the Drew sweatshirt, you'll need to factor this in when positioning the neckline on yourself.
Mark the position of your bust apex - the fullest part of your breast - in pen or pencil, on the pattern piece. Now, lay the pattern out flat, and mark the seam allowance roughy two thirds of the way along the front raglan seam.
Draw a vertical line, parallel to the grainline or "place on fold" arrow, all the way down the pattern through your bust apex mark. We'll call this "line 1".
Next, draw a horizontal line all the way across the pattern through your bust apex mark - this line needs to be perpendicular (i.e. at a right angle) to the grainline - we'll call this 'line 2'.
And finally, draw a diagonal line from the bust apex to the marked seam allowance along the front raglan seam - we'll call this 'line 3'.
Now it's time to grab those scissors! Starting at the centre front, cut along line 2, and then pivot at the bust apex to cut along line 1 all the way down to the hem.
Next, starting at the bust apex cut along line 3, and stop just before the seam allowance you marked earlier.
From the other side of the seam allowance, cut from the edge of the front raglan seam and stop just before the seam allowance to create a hinge.
Cut along the remainder of line 2, starting at the side seam and leaving a small hinge at the bust apex.
You should now have two hinges - one at the bust apex and one at the front raglan seam. They're delicate so be gentle with them!
Next, get a piece of paper slightly bigger than your front bodice pattern piece and draw two horizontal parallel lines on it, with the distance between them equal to the amount you want to add to the pattern - for a knit garment, reduce this amount by 10-25% to account for the stretch of the fabric.
Carefully place the pattern pieces on top of the paper. With tape or glue, stick the upper part of the front bodice to the piece of paper, aligning cut line 2 with the upper line drawn on the paper below. Draw vertical lines to extend the centre front and grainline or "place on fold" arrow.
Take the centre front piece which isn't attached to the rest of the pattern with a hinge, and stick it to the paper, aligning cut line 2 with the lower line drawn on the paper, and the centre front edge with the centre front line extending from the upper part of the bodice.
Now using the hinge you created along the front raglan seam, gently hinge the other side of the pattern downwards until the bust apex is sitting on the lower line drawn on the paper below, and stick in place.
Lastly, using the hinge you created at the bust apex, hinge the side seam part of the pattern downwards so that cut line 2 sits flush with the lower line drawn on the paper below, and stick in place.
We're almost there! Now we just need to tidy up the pattern piece :)
Mark a point at the side seam that is the same width in from the side seam as the amount you added widthways at the bust (illustrated by the pink arrows above), and the same distance up from the hem as the amount you added lengthways along the side seam (illustrated by the pink arrows above). Redraw the side seam and the hem tapering into this point.
This will remove the extra volume added at the waist that you don’t need, but keep the volume you want to add in at the bust, whilst also making sure that the side seam remains the same length overall so that it still matches the back bodice.
Finally, smooth out the front raglan seam if this has been distorted, and remember to transfer any labels, notches etc. onto your newly drawn seams.
All that's left to do is cut away any excess paper to leave you with your newly adjusted front bodice piece, which should look something like this:
And you've done it! I hope you've found this post helpful and now feel ready to go forth and do a full bust adjustment on your favourite raglan seam sewing pattern.
