Megan Neilsen Matilda Dress - Easy FBA Tutorial

Before I sewed up my Matilda dresses, I did a minor FBA to the flat pattern pieces. One of my dear readers expressed in interest in how I did it, so I decided to write out a proper blog post about it. It is extremely simple, but it worked out perfectly for me. Before we go on to the tutorial, I wanted to make a couple quick notes.

First: When the Matilda sewalong comes up, there will probably be a better and much more in-depth tutorial. This is just a "shortcut FBA" if you will. The reason I mention this is because this FBA will not work if you need more than an inch or maybe an inch and a half added to the original pattern measurement. I wanted just a smidge more room across the bust to insure that there wouldn’t be any gaping at the buttons.

Second: If you have the printed version of the Matilda dress pattern, I would highly recommend tracing off the necessary pieces in case of a mishap. If you have the PDF Matilda pattern, it is easy enough to print out just the front and side front bodice pieces, unless you don't want to use more ink and paper. In which case, you can still trace it off by hand. Now that is out of the way, we can get on to the tutorial!

What you will need:

The front and side bodice pieces of the Matilda dress

A ruler (curved if you have it, straight if you don’t)

Drawing utensil (pen, pencil, marker, etc.)

We will start with the side front bodice piece. For the majority of my dress, I used the M size. As you can see in the following picture, I have marked the size M line with green, and the size XS line with pink. Now some of you might be like, “What does the XS line have to do with anything? I thought we were adding to this piece, not subtracting!” Don’t worry! I haven’t gone crazy yet. If you look at the picture, you will see that the XL line is further to the right than the M line. If we tried to use the XL we would end up with a weird shaped pattern piece that wouldn't fit anybody. I am merely using the XS line as a guide on how far out I want to trace my new line.

Starting a couple inches down from the top, draw a line from the M line to the XS line ending at the notch line. (Marked in yellow above.) I used my curved ruler, but if you only have straight rulers, you can either freehand it, or draw a straight line, and then add a gentle curve later using a bowl or something else with a slight curve to it.


Here is my line:

Next we are going to draw a line from that notch to the waist. Except, this time we are going to do it the opposite way: from the XS line to the M line.

You can now repeat the same process on the front bodice piece. The only difference is that this time you would trace from the M line to the XL line (i.e. the line furthest away from the M line.) at the bust notch, and then back to the M line at the waist.

And that's pretty much it! I told you it was super duper easy. I marked the original size M in orange highlighter so you could see how much we added. Again, it isn't an enormous amount, but it will add about an inch overall. If you needed to add a little more, it wouldn't be difficult to just extend your line out further at the fullest part of the bust. If you needed to increase the bust by a significant amount it would be better to do a proper FBA so that the pattern pieces don't become distorted. (Mary has a wonderful tutorial for doing an FBA on princess seams that you can find here.)

If you have any questions be sure to let me know in the comments below. I'm not an expert at writing tutorials quite yet, so I am open to any helpful feedback!

If you haven't already, be sure to check out the Matilda pattern tester roundup on the Megan Nielsen blog. There are so many fantastic different versions of the Matilda dress. It is making me want to sew up a couple more!

Thank you!