Sunday 23 September 2012

Small bust adjustment tutorial - Part 1

As promised, I am going to do a series of tutorials on small bust adjustment ("SBA"), as when I was researching the subject, I was surprised to find that whilst FBAs are often talked about, SBAs simply don't get half the attention. I suppose it is not that surprising - if your clothing is too small around the bust, then you've got to do something about it to make it fit; on the other hand, you could make do just fine without having to adjust the pattern (a padded bra, anyone?) if the top/dress is a little too loose.

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;
  • Scissors;
  • 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 2 - find the vertical waist dart, and draw a vertical line through the centre of the dart, extending it upwards. (Line 1)

Step 3 - draw a (almost) horizontal line connecting the centre of the side bust dart, extending it towards the bust point. (Line 2)

Step 4 - draw the stitching line around the armhole, so we don't get confused by the seam allowance.

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 8 - Cut Line 2 from side seam towards the intersection of all three lines (roughly the bust apex), leaving a tiny hinge there. 

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 10 - Pivot the left piece by pivoting it upwards and rightwards, overlapping on the waist dart whilst keeping Line 1 roughly vertical and parallel to the centre front. Tape in place when you're happy. 

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)

This type of bodice front with a waist dart and a side bust dart is really common, so I hope this tutorial is helpful. More tutorials to come to show you how I've done a SBA for other types of bodice pattern pieces! 

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! 


  1. Thanks for sharing your tutorial! I'm looking forward to seeing the next part!

    1. No problem at all ;-) and I'll try to do the next one in the next couple of weeks x

  2. Thank you so much for this detailed tutorial! I was putting online last night looking for information about vintage pattern adjustments that suit my figure (narrow shoulders, small bust), and BAM there was your blog!
    I too suffer from a small bust and though my other measurements are close to what vintage patterns are usually designed for (waist 26, hips 35), my bust doesn't measure up, even with a miracle push-up bra! I can't wait to try your technique on my latest vintage obsession: Simplicity 4905!

    1. Oh thank you - you are too kind! I know I promised another tutorial, and that this was supposed to be the start of a series of tutorials based on different types of bodices, but I've not managed to do my second one as yet... that said, I am planning on doing one shortly so keep your eyes peeled ;)

      Speaking of vintage patterns - it is so much trickier to fit, isn't it?! I am currently fitting a toile based on a lovely vintage pattern, and it's giving me a lot of headache indeed! I will report back shortly :)

  3. Thank you so much for this tutorial. I I have this pattern and I have wanted to make this for such a long time. I was afraid because I am, Uhm, what one calls "flat chested." Your excellent tutorial will guide my along and give me the confidence I need.

    1. That's great - I'm always pleased to hear when a tutorial might be useful to someone. We should have a club for people that need SBAs :D I have to say, though, that these days I feel a lot less sorry for myself having learned how to make my own clothes to fit better (thereby not highlighting the lack of curves in that particular area). Good luck with the dress!

  4. This is so helpful! I have a few questions though. Do you re-draft to your own actual bust point or go with the pattern in this regard? Most people with a smaller bust also have higher bust points than a larger cup size (no weight pulling the bust down). Also do you find that adjustment leaves the waist too small? When you swing across you lose some width from the waist, if you don't want to lose this width would you grade up a size at the waist before making the SBA? Sorry for lots of questions, I am just beginning my journey into SBAs!

    1. Re the bust point, I think step 10 should have the effect of bringing it upwards. On the waist, yes, I do! However as I prefer a relatively tight fit, it normally works quite well for me without having to adjust. If the waist turns out a tad too small, what I often do is adjusting the darts by making them more narrow, and measure the altered pattern flat to check that the waist will still fit right. I hope this makes sense!

  5. Thanks for this post! Just what I needed to use the Lisette pattern for my 13 year old. Did not even know it was drafted for a C cup…no wonder it was huge on me!

  6. Fantastic post! I'm about to make my own lisette traveler and enjoyed your review. I have a silly question - how do you know how much to take out with the pivot (if you didn't make pattern before)? Is there a conversion between cup size and SBA adjustment? Many thanks :-)

    1. First of all, sorry for the very tardy response! In case it is not too late -- I used my measurements and flat measured the patterns to check. I don't have a conversation table, sadly, but depending on how much ease you want I think measuring the pattern is the best bet. Good luck and happy sewing!

  7. You're a godsend! I know this is an old post but I time hopped all your glorious links to here somehow.

    "You know by now if you need an sba" don't i know it. I wondered why I always prefered flat tops without darts. I thought it was the room; I also felt a touch ridiculous with these dart points just flapping around all willy nilly.

    I don't like bras. And frankly I dont much like having boobs at all. So bust allowances are quite silly for me. I'm not flat flat, but I find myself wearing chest compressors over bras anyday cause I want my bits to be secure not perched over some shiny lace teacups wobbling afraid of heights near my chin screaming "WHY AM I UP HERE I DON'T EVEN EXIST MOST DAYS!" Also, padded bras on the fattiest part of my body in Australian Summer? What white victorian cravat choked devil thought that was a good idea?

    i have a selection of nice tops for when I do feel like wearing a bra which is so rarely, i only do it when I am wearing nice tops.

    So this is perrrfect for my every day comfortable wear. Hell, my dresses. One of the main reasons I don't wear dresses is cause I feel ridiculous. WHAT AM I SUPPOSED TO DO WITH THIS AIR POCKET ON MY CHEST?! KEEP MY GROCERIES IN IT?! HOW ABOUT SOME GRAPEFRUIT?! I GOTS ME SOME LEMONS!

    I'm really proud of my shoulders and arms though and I definitely come off as "linebacker in a dress" but I like myself that way so who cares? That's the reason we sew right?!


    its 5am and i haven't slept.

  8. Thank you so much for this! I am here because I am working on the Penny by Colette. Good to know that they draft for a C-cup and that's why it looks so silly! I have big air pockets on my chest. I am definitely going to try this and I'm sure I'll be able to come to a better fit.

    As for rotating your photos, try rotating them in another program prior to uploading. You can use MS Paint or if you have Windows you can just right - click the photo in the folder and rotate it. Then it will be good to go once you upload it. It was not distracting with them in this orientation though.

    Thanks again!

    1. Thank you for stopping by! I'm so glad that it's useful ;)


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