Fitting Commercial Patterns is a very popular workshop for home sewers and textile teachers. This week I've been going all-out to improve the workbook materials for this workshop in preparation for some professional development training I'm delivering in Melbourne next week to the Victorian VET textile teachers. I've decided to share a section of that new workbook in this post, covering the Full Bust Adjustment (FBA) on an existing shirt pattern.
The shirt pattern in question has no bust dart included in the pattern. So for anyone with a cup size greater the B you'll need an FBA alteration to create a better fit and a more balanced garment.
- Measure straight down from the original neck point of the shoulder line toward the bust area to mark the Front length to Bust Level.
- Square across from the Centre Front (CF) line for half the Bust Separation to find the exact Bust Point.
- Extend these lines, so they run in four directions from the bust point; toward the hem and the side seam.
- Cut your pattern into four pieces ready for the pattern alteration.
- In this example I'll be using craft paper to distinguish the original pattern from the alteration and I'll be adding 1.25cm (½") in front length and the same in bust circumference.
- Using the CF as a stable balance line for the placement of pattern pieces: begin by gluing down the top right section of the pattern.
- Mark a new line 1.25cm (½") from the bottom of this pattern piece to add the extra length required over the bust. Match and glue the bottom right side pattern piece along the CF line.
- Keep the shoulder seam together, angle the top left pattern piece 1.25cm (½") from the BP. this move adds extra width in the front pattern across the bust area.
- And finally, keeping the hem together, angle the bottom left pattern piece to include an extra 1.25cm (½") at the BP.
- All of these alterations have resulted in extra length on our front side seam. You'll turn this extra length into a bust dart.
- Measure 3cm away from the BP, along the new dart area, to mark the start point for the stitching line for your dart.
- Join this new point to the outside edges of the extra fabric on the side seam to form a bust dart. These are the stitching lines for your dart.
Although these pattern alterations are not as exciting as creating new patterns, they are so valuable in our understanding of fit and how we can constantly improve the patterns in our stash. Let me know if you have any questions, I'm always happy to help. :)
Comments
If you can give me more detail about your measurements and usual fitting experience I may be able to work out for you how much is needed in your alteration.
I draw my bodice block using pencil and cardboard .
By your reply it seems that I can draw the bust dart bigger than the normal 2" for a "B" cup.
This would then give me a block with the cup alteration built in, saving time later on.
Incidentally it took me ages to work out why my skirts never looked right. The answer was that my hip line is 7" below my waist and not 9" as found in so many commercial patterns! Proportion is everything!!!
Thank you very much for your answer and for your terrific website.
I would imagine there would be a good market in supplying blocks made up by using a client's own measurements. I am 70 and a bit old to contemplate such a venture but I am sure someone could start up that type of business!
Marian
Yes, proportion is everything in pattern making. We need all the curves on the pattern to be in the same place as the curves on our body.
If you drafting system permits you to make the dart bigger then it's best to do that in the beginning. Please be sure to also check that your centre back length to waist is also accurate so you don't get too much fabric pooling above the waist in the back bodice.
Your suggestion for personalised blocks is a good idea but largely a complex process requiring personal attention to each clients measurements. The more technically savvy may be able to produce a bit of software that ensures accuracy in fit using individual body measurements. My pattern making work is largely manual and I'm also at the latter end of my career and not really that interested in chasing such a big piece of work. I believe there are some companies out there claiming they can produce individual blocks but the results I've seem are not all that useful. I'm sure there will be many systems in the future that will be able to cater to that market.
Let me know how you go with your block and remember I'm always here to answer any of your questions. :)
Cheers!