After being in denial for quite a while, I finally thought, if I'm making my own clothes, shouldn't I do everything I can to make sure that they actually fit me well? It was my wearable toile of Simplicity 2444 that prompted me to make a SBA, as the use of the contrasting fabric made it absolutely clear that I had to do something about the excess fabric.
So he we go - tutorial 1 - introduction and illustration on Simplicity 2246 (Lisette traveller)
Do I need to do a SBA?
Typically, the big 4 pattern brands use a B cup for their patterns (apart from the Amazing fit (and equivalent) patterns with different cup sizes), and Colette uses a C cup (that's why I've been too scared to actually try it out!).
When I was looking at McCalls 5927 (with A-D cup sizes) from my stash, the instructions included a helpful guide/chart as to how to find out what cup size you are when it comes to sewing patterns. I'm sure there will be plenty other patterns with such a guide (and it's probably available online too), so it's worth checking that out first.
I would say that you would probably know by now if you do need a SBA. The signs to look for are:
- Bagginess around the chest area when the dress/top fits well elsewhere;
- Side seams not straight, with the top part shifting towards the back;
- Waistline not level, with excess fabric in the centre front.
Basically there is too much fabric both horizontally and vertically, so we need to fix both.
What do I need?
- Ruler (I usually use a French curve but a normal ruler will do too) and pen/pencil to draw on the pattern pieces;
- Clear tape;
- Bodice front pattern piece(s).
Basic bodice pattern - I'm using Simplicity 2246 (Lisette Traveller) for illustration
Step 1 - shorten or lengthen pattern as usual
Step 3 - draw a (almost) horizontal line connecting the centre of the side bust dart, extending it towards the bust point. (Line 2)
Step 5 - measure the stitching line around the armhole, and pick a point that is approximately 1/3 way from the bottom (side seam rather than shoulder seam).
Step 6 - draw a line connecting this point (from step 5) and the intersection from Line 1 and Line 3 (approximately the bust apex). We'll call this new line Line 3.
Then it's time to cut! As our objective is to remove the excess horizontal and vertical fabric, the SBA is essentially a pivotal adjustment, so we'll be cutting the pattern up a bit, leaving little hinges from which we can pivot the pattern.
Step 7 - cut from the bottom of Line 1, through to Line 3 without stopping, leaving a hinge at the armhole point.
Step 9 - Adjust Line 2 by pivoting the bottom left piece upwards, overlapping the pattern piece on the side seam. When you're happy, tape it in place. Based on how much of a SBA you need, it may be the case that you could eliminate the side bust dart altogether. It depends on how much design and wearing ease it is built into the pattern, quite often I would eliminate the bust dart so there are 2 less darts to sew!
Step 11 - Reduce the length of the pattern piece on the right (towards the centre front) to align the bottom of the pattern piece, as all the pivoting in the previous steps will have shortened the bodice front. Because of this, I would always be careful as to how much of a petite adjustment you do at the beginning (step 1). I made the full petite adjustment for my Little Lisette traveller and the waistline ended up being just that tiny bit too high.
Step 12 - Redraw the waist dart (and the side bust dart if you haven't removed it altogether in step 9). You should end up with a narrower dart because you will have already reduced the width of the waistline by doing a SBA. Also remember to adjust the connecting pattern pieces if necessary.
That's it! It's really quite simple. I've used the exact same method for McCalls 2401 (blurry version and spotty version) and it worked a treat too.
Here's what my McCalls 2401 front looks like (it does not have a waist seam)
P.S. some of the photos simply refuse to be rotated when uploaded! Apologies for those but hopefully you can still see what I mean by turning your head/neck instead. And if anyone knows how I can fix this, please let me know!