Thursday, 12 September 2013


 Welcome back to sew-along post # 2. This post i am going to show you how to complete an FBA & SBA on the Mae blouse. I did mention in yesterday's post that Bluegingerdoll patterns are drafted to a D cup, which received a round of applause from a few readers, Yay! But obviously for those of you with different cups sizes, not so Yay. So instead of being restricted by your cup size, i  think it is an important to know how to complete Full bust adjustments or small bust adjustments, that way it doesn't matter what your bust size is, because you will be able to adjust any pattern to your right bust size. And  cup size wont rule your life, and that's a Yay all round!

So before we start, just a quick recap on yesterdays post. If you are sewing along you should have your fabric picked out, pre-washed and ready to go, your pattern traced to your size,  a muslin sewn up and tested the fit and  established if you need to make any adjustments  for a better fit.

OK lets jump in shall we:

What is an FBA & SBA? 


 In simply terms:
Full Bust Adjustment ( FBA) - You  need some more room for your girls, it is too tight in the bust area, they are getting squashed/flattened and  they need some air.
Small Bust Adjustment ( SBA) - You need less room for your girls, they is drowning in there.

So how do you know if you need to complete either a FBA or SBA?

 Simply! Just refer to that handy size chart on the back of the pattern envelope and:

FBA - If your bust measurement falls into the larger size column than the rest of your body.
SBA If your bust measurement falls into the smaller size column than the rest of your body.

Another way to tell, is if you’ve already made a muslin, you might notice that the bust area just isn't right i.e too loose, excess fabric, fabric sagging or too tight, the bust apex sitting too low or its  just simply looking just plain weird. Then you will need to complete a bust adjustment.  

Calculate your FBA or SBA 

Calculating your FBA & SBA is easy. You just need to figure out what size you would be if you used your  bust measurement... Got it? OK, then compare this size to what size you would if you used your other measurements ( waist, hip) as your size. Then grab your front bodice pattern piece and measure the distance between these sizes. TA DA! This is your FBA or SBA amount.Which ever adjustment you are going to make, this is the amount we will either increase or reduce the bust by.

What tools do i need?

Grab your traced Mae front bodice pattern piece, pencil, ruler, scissors, sticky tape and pattern paper. 
* Please note the bodice images i am using throughout the tutorial, all are working with the seam allowance included.

First up i will show the steps in completing an FBA, the SBA follows exactly the same steps, but instead of spreading the pattern piece for more room we overlap it for less room. For learning purposes it is easier just to focus on the one bust adjustment first up.


To being with, cut off the sleeve section on the Mae bodice front.




Get your pencils out and draw your slash lines onto the bodice front, as follow:

Line 1 - Draw 1/3 up the armhole to the apex and then straight through the centre of the vertical dart down to the hem line.

Line 2 - There is no side dart on the Mae blouse so you need to  slant the dart as if there were one. So draw Line 2 slanted from the side of the bodice and extending to the bust apex.

Line 3 - Draw anywhere below the bust apex in the section shown in the diagram.

Step 3

Grab your scissors ( not the fabric ones!) and cut line 1 starting from the hem line and then up to, but not through,  the armhole edge. On the armhole edge, snip a tiny amount in towards line 1, but not completely through,  to create a tiny hinge at this point. ( See diagram below)
Then cut line 2  up to line 1 at the bust apex point, again not right up to line 1, leave enough room to create another tiny hinge.




Step 4 

 Now you need to tape down  the front section of the bodice, to keep it in place. So i would recommend placing some new pattern paper underneath the bodice piece you are altering and tape it onto that.

This is where we start to make the adjustments. Pull the bodice pieces apart at the horizontal arrows along line 1, using  the FBA amount you calculated that  you  would need for the FBA. You need to keep the long edge of line 1 parallel.  So to do this, keep the bodice completely  flat,  with the armhole going up  and the side panels dropping down - Line 2 will open up and form the side dart.
Now you need to keep these two side sections in place, at the pink dots on the diagram, so tape em down

Step 5 

Our last line we need to cut is Line 3. So cut  line 3 straight across and lower it  until the  bottom edges of the pattern sections are even. Tape it down at the pink dots, as shown on the diagram.


 Step 6  

Now because you have already taped your bodice pattern piece onto new pattern piece, you will have noticed that you have filled in these newly created FBA spaces. If you haven't taped it down onto new pattern paper, then you will need to fill in the openings with new pattern paper. Nearly down, all you need to do now is re-draw your darts on the bodice,  as shown on the diagram below. Most probably you will also need to fix up your seam allowances, so do that now as well.


Step 7 

 Tape  those sleeve back onto the Blouse, and cut out your new bodice pattern piece! 



As i said at the beginning of the post, to complete and SBA on the Mae blouse, you basically follow the  steps from start to finish exactly the same as the FBA i.e draw your lines, cut them etc but instead of spreading the pattern at the 3 drawn lines, as you would for an FBA ,you simply just overlap the pattern at these same lines, using the SBA amount you have calculated. Easy!



FBA & SBA -  Important things to note!

*Making these bust adjustments will change the size of the waistline (IE make it smaller or wider) so you may need to make an adjustment at the waistline to maintain your correct size.
 *Depending on which bust adjustment you have completed and how much you have shifted the pattern to allow for more room or less, you will have to 'true' your patterns style lines IE at the side seams, hem line etc. 
* Keep the adjusted bodice pattern piece for your future reference, don't chuck it out!
* Once you have adjusted your bodice pattern, either with an FBA or SBA make another muslin and test again.

I hope this helps. If you have any questions, please feel free to ask me!

Catch ya tomorrow for the next sew-along post ;)



No comments

Post a Comment

Thank you so much for the visit and leaving a comment!
I totally appreciate them all!

Happy sewing!


© Bluegingerdoll - Vintage inspired sewing patterns, sewing tips and tricks | All rights reserved.
Blogger Template Created by pipdig