Top Draftalong # 29 – Bust Dart Enlargement

Ok so here goes. This is a LONG post peops. I racked my brains trying to seperate this into more bitesize individual posts but each stage of this is so interlinked with the next that I decided to just keep it all together in one place. Recommend sorting yourself out a glass of wine/coffee/tea/beer (delete as appropriate) and put your feet up. Ready?
Okey dokey. Firstly I should mention that I have decided to ditch the block pattern from the book. (Eeeep! Yes the one that I’ve spent all that time on!) in favour of the Sorbetto from Colette patterns. The issue I’m addressing in this post was exactly the same on both patterns, but the Sorbetto just seems to suit me better overall and I just think for me it would make a better block/sloper pattern in the long run. You may recall the stage I was at here.  I had pinned out some excess fabric at the armhole and needed to transfer those markings on the toile to the paper pattern so that I could rotate this unsightly dart in the armhole and add it into the bust dart instead…(the first few photos were taken at night so apologies for the poor lighting)

Here’s my toile (I used no sew interfacing to make it. Top tip. It works brilliantly!) with the armhole dart marked out where I’d had it pinned…

I layed my tissue pattern on top…

and traced the armhole dart onto it…here’s the toile and the tissue pattern side by side…

I then extended a line through the centre of each dart until they crossed….

I cut along the lines at the centre of each dart, stopping just short of the crossover point to creat a hinge/pivot point…

I closed off the armhole dart by lining up the bottom dart leg on top of the top dart leg. This results in the bust dart enlarging by the exact same amount….

I then secured with masking tape (easier to reposition than sellotape and you can iron and draw over it too. Win win win!) I called it a night at this point and spent the night tossing and turning and muttering about armholes and bust darts in my sleep…apparently!

Next day (!) I secured a slip of paper with masking tape on the underside of the new dart…

This was a tricky one to do (and photograph) but I eventually managed to fold out the dart with the side seams above and below the dart lined up as they would be if I were constructing the dart on the garment (they are lined up honestly! It’s the camera angle in this photo that makes it look wonky)…

Then cut along the side seam…

and open the dart out again…ta dah!! New “boobalicious” bust dart…

Of course, now the armhole is all wonky! Closing up the armhole dart has raised the bottom of the armhole too high and at a funny angle. Place a piece of paper behind the armhole and tape in place as before…

I held the pattern piece against myself to get a rough idea of where the new armhole curve should start on the side seam and marked it on the pattern. Back on the cutting table I drew in the new armhole shape starting at the point I had marked on the side seam,(make sure the first 2-3mm of the armscye is at a right angle to the side seam or you’ll get a “peak” when the side seams are sewn together) drawing a smooth curve and blending it into the upper part of the armhole curve. You can use a French curve (visible in picture) but in the end I printed off a copy of the front armhole section of the original PDF pattern and used this as a template to get the curve just right

A quick snip later…armhole curve sorted. That looks better! 

Here’s my new pattern piece. Unsightly armhole dart rotated into bust dart and the armhole curve reshaped. So we’re done right?

Nope! One final adjustment. This is the original pattern lined up at the armhole. See how the front piece is marginally longer than the back? Well this is where my pattern cutting classes kicked in. Somewhere in the deep dark recesses of my befuddled brain, I remembered….

The width of the dart…

Is directly proportional to the “extra” length at the hem of the front pattern piece…because of course, when the dart is closed, this extra length is taken up…

Applying the same principle to my newly adjusted pattern….
I measured the width of the new dart…

and worked out how much extra to add to the hem to compensate for the extra length that would be taken up by the wider dart…(does this make any sense??)

So here is my new pattern….

I’m happy to report that everything lined up perfectly when I made my toile (that post to follow) so I was super chuffed with myself and this process has marked a bit of a Eureka moment for me. Both in fitting and the pattern manipulation process. It’s a case in point that “every action has an equal and opposite reaction”.  Each alteration will impact on another part of the pattern and generally require a compensatory alteration elsewhere to get everything to line up again. It’s this emerging awareness of the “bigger picture” that feeds the slight addiction I have to pattern drafting. It’s a bit of a love hate relationship because it has me swearing and tearing my hair out as much as it has  me jumping for joy at a new principle understood!

I tell you what though…I never thought I’d be referencing Newton and Archimedes to in a blog post about how to make a top that fits me!! Hilarious! Hmmm. Professor P…has a nice ring to it…;)

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  1. aviewintomyworld August 25, 2011

    excellent post portia šŸ™‚
    i’m still stalled at the erm, well the starting point but am hoping to get to it over the next couple of weekends!

  2. Sheri August 25, 2011

    Portia, my dear, this has been a tremendous help to me! I’m not sure I understand it completely, but I think I got it. I will know better when I try it myself. I really appreciate the top draft-along, your pictures, and explanations. Thanks ever so much! Hugs, Sheri

  3. A.J.A. August 29, 2011

    Excellent! So this is an adjustment you can do to get rid of the fabric from a gaping arm hole? Did you find the armholes on the Sorbetto to be snug? I even cut the last one with the armhole at the largest size, and it still wasn’t what I’d call “roomy.”


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