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Bust adjustments

bust-hero-updated

In today’s post we will be covering bust adjustments. This tutorial is close to my heart, as I usually have to execute a full bust adjustment on every pattern I make. I like to make this pattern adjustment before sewing my muslin. This allows me to take a more accurate look at any fit issues I might encounter in my mock-up.

Do I need a bust adjustment?

Most pattern companies draft patterns based on a B cup. Colette patterns are the exception to this rule as we draft for a C cup for sizes 0-18, and a DD for sizes 20-26.

If you’re making size 0-18 and have an A or B cup, you will need a small bust adjustment or SBA. If you have a D cup or larger, you will need a full bust adjustment or FBA.
For sizes 20-26, if you are a D or smaller you will need an SBA, and if you are a DDD or larger you will need an FBA.

Determine your sewing cup size

1) Measure your full bust. This should be around your ribcage and over your bust apex.

highbust

2) Measure your upper bust. This is the area of your chest right below your underarm.
3) A difference of 1″ means you are an A cup, 2″ is a B cup, 3″ is a C cup, and so on. Don’t worry if this is very different from your actual bra cup size!

What size should I cut?

Now that we know whether or not we need a bust adjustment it is time to determine what size we should start with. When you require an FBA or SBA, picking a size isn’t always as straightforward. Here is the technique I like to use:

1) If you are making a size 0-18 take your upper bust measurement, then add 3″. This will determine what size you would make if you were a C cup.
2) For sizes 20-26 add 5 inches to your upper bust measurement, this is the size you will make your bust adjustment to.
3) The difference between your actual bust measurement and the size you are cutting is the amount your pattern will need to be adjusted. This is your bust differential measurement.

For example:
If your upper bust measures at 33″ and your full bust measures at 38″
33+3= 36, this means you would cut a size 6
38-36= 2, this is the amount you need to add to the bust of your Aster.

You’ll need:

  • Your Aster Blouse Pattern
  • A clear ruler (I use a 2” x 18”)
  • Pencil
  • Pattern paper
  • Paper shears
  • Tape

The Process: FBA

01-bust

1) Prepare your pattern by tracing the front bodice, transferring all darts, notches, and markings. Also mark the sewing line at the armscye.

02-bust

2) Draw a line through the center of the side dart extending through the dart point to the bust point (1 1/2″ beyond the dart apex) We will call this line “A”.

03-bust

3) Draw a line from the bust point to the hem of the blouse. This line should be parallel to the grainline. We will call this line “B”.

04-bust

4) Draw a third line from the bust point to the armscye sewing line (at roughly the center point). This is line “C”. You will now have three lines drawn on your pattern.

05-bust

5) Using your paper shears, cut through line “B” starting at the hem, pivot at the bust point and continue cutting through line “C” stopping at the armscye sewing line. Cut a small notch through the seam allowance at line C, leaving a small paper hinge at the sewing line.

06-bust

6) Next, cut through line “A” starting at the side seam, leaving a small paper hinge at the bust point.

07-bust

7) Now the pattern is slashed and ready to be opened up the desired amount (bust differential). Divide your bust differential by 2. This is the amount that will need to be added to your pattern piece. On your spare piece of pattern paper, draw two parallel lines that are that distance apart.

08-bust

8) Very carefully lay your slashed pattern on top of the pattern paper. The hinge that you created at the side dart should allow you to maneuver your “B” lines so that they lay on your parallel guidelines. Carefully tape down your tissue pattern to the pattern paper, leaving the center front portion free below the lengthen/shorten line.

10-bust

9) You will notice that the waistline of your pattern is now two different lengths. A full bust requires additional length. Use the lengthen/shorten line on the center front to lengthen the center front so that the hem aligns with the side front.

11-bust

10) Redraw dart legs by extending the existing dart lines to meet.

12-bust

11) Reposition the last 2 button placement marks so that they are 2 3/4″ apart, consistent with the rest of the pattern.

13-bust

12) Finish by trimming away extra pattern paper and taping as needed.

No additional adjustments need to be made to the rest of the pattern, as only the dart uptake, and the center front length have changed.

The Process: SBA

01-bust

1) Prepare your pattern by tracing the front bodice, transfer all darts, notches, and markings. Also mark the sewing line at the armscye.

02-bust

2) Draw a line through the center of the side dart extending through the dart point to the bust point (1 1/2″ beyond the dart apex) We will call this line “A”.

03-bust

3) Draw a line from the bust point to the hem of the blouse. This line should be parallel to the grainline. We will call this line “B”.

04-bust

4) Draw a third line from the bust point to the armscye sewing line at the center point. This is line “C”.

05-bust

5) You will now have three lines drawn on your pattern. We can now manipulate the bodice to create less room in the bust. Using your paper shears, cut through line “B” starting at the hem, pivot at the bust point and continue cutting through line “C” stopping at the armscye sewing line. cut a small notch through the seam allowance at line C, leaving a small paper hinge at the sewing line.

06-bust

6) Next, cut through line “A” starting at the side seam, leaving a small paper hinge at the bust point.

14-bust

7) Now the pattern is slashed and ready to be minimized at the bust the desired amount (bust differential). Divide your bust differential by 2. This is the amount that you will need to reduce by. Keeping in mind the amount you wish to reduce by, draw a line parallel to the center front portion of line “B”. I am reducing this pattern by 1/2″ at each bust point, so my line is 1/2″ away.

15-bust

8) Maneuver your pattern so that line “B” lies on your reduction line. Secure lines “C” and “A” with tape. Tape line “B” above the lengthen/ shorten line.

16-bust

9) The center front of your pattern will be longer than the side piece. To even up the waistline, cut along the center front lengthen/shorten line and shorten.

17-bust

10) Reposition the last 2 button placement marks so that they are 2 3/4″ apart, consistent with the rest of the pattern.

18-bust

11) Redraw the dart legs using the original dart point.

No additional adjustments need to be made to the rest of the pattern, as only the dart uptake, and the center front length have changed.

After you have completed your bust adjustment, you can cut according to the fabric layout for the size you are making. Cut notches and use a water soluble marking tool to make all markings.

On Monday, Sarai will cover staystitching and interfacing. This gives us the weekend to complete our pattern adjustments and cut our fabric.

The Aster Sewalong

  1. Welcome to the Aster Sewalong! (16 Comments)
  2. Gather fabric and supplies (49 Comments)
  3. Cutting and fitting guidelines (50 Comments)
  4. Bust adjustments (114 Comments)
  5. Staystitching and Interfacing (10 Comments)
  6. Bust darts and shoulder pleats (12 Comments)
  7. Sewing the yoke (33 Comments)
  8. Sewing the side seams, neckline, and placket (36 Comments)
  9. Sewing and setting the sleeves: Version 1 + 3 (6 Comments)
  10. Sewing and setting the sleeves: Version 2 (5 Comments)
  11. Hem and finish! (5 Comments)
  12. How to share your finished Aster (24 Comments)
  13. Your finished Asters! (8 Comments)

Comments

Shasta

Where can you look to see what size bust a pattern is written in? I’m just starting out, so this will be my first time doing a SBA, and I’ll most likely have to do this for A LOT of patterns I have.

Haley Glenn

Unfortunately, most pattern companies do not include this information on the pattern envelope or in the instructions. It is safe to assume most commercial patterns are drafted for a B cup unless otherwise indicated on the website/sewalong.

Valerie

I am upper bust 38″. Full bust42″ Waist 37″ .Hip 42″

Which size should I start with ?

Haley Glenn

I would start with a size 12, doing a full bust adjustment to open up the bust a total of 2″.

Valerie

Many thanks for your help.

Hi! So, it looks like my high bust us 34.5in my bust is 36 (or maybe even 35.5) my waist is 29in and my hips are (at the largest point, not just around hipbones, right?) 39 (but that is more around my upper butt, is that ok?). I think I should cut a size 8 (you pick the closest right?) and then bring the bust in 1″?

Since nursing and weaning my second child earlier this year, my boobs have deflated. Before that, I made a perfectly fitting dahlia and sewed a size 8 bust with no adjustments ( to the bust). When I try it on now the whole top is loose, maybe because that is the dahlia style? Anyways, I am just not sure that a 1″ bust decrease would be enough to remedy the dahlia top (not that I plan to, I am just comparing my size to try to understand my new size). Meh, just wanted to get your thoughts.

So, with these it would seem I should sew a muslin. I haven’t sewn anything with buttons, so when you sew a muslin for a button closed garment, do you just hold the two side together?

Thanks!
Jen

Oh, and I wanted to mention that after the boob deflating, I sewed a moneta that fits really well and chose a size small top based on a 34.5 upper bust. What that a wrong choice, but it just ended up fitting? Like, I think if I would have added 3 inched and chose the medium top it would have been baggy. Sorry to bring in these other dresses, I am just trying to understand what size I really am!!!!

Haley Glenn

To me it seams like you are a pretty true size 8, with the exception of needing an SBA. Knit dresses like Moneta are very forgiving in fit, it is also highly dependent on the amount of stretch your fabric has. Though, I am usually a large, I have also made a medium in Moneta when working with very stretch fabric.

Haley Glenn

I would make a size 8 and decrease by 1.5″ in the bust, especially if your bust measurement is leaning more towards 35.5″. When sewing a muslin for Aster (or any garment with center front button closures) I usually sew the side seams up, then pin the front closure at the button placement markings.

Great. Thank you so very much!

Becky

Thank you for the great tutorial on picking a size to start and determining the amount of the adjustment!

I have yet to trace out my pattern to make any adjustments, but will be doing an SBA and probably lengthen the blouse, too, as is my preference for tops. Would it make sense to lengthen the newly-shortened side of the SBA adjustment to meet the length of the center?

My other idea is to complete the SBA per your instructions before I decide on the length at all, then perhaps lengthen the whole thing afterward. What do you think?

Haley Glenn

If would lengthen at the side bodice instead of shortening at the center front. Then you can avoid having to redraw the button placement. Remember to lengthen the back bodice the same amount added to the front bodice.

Becky

Thanks!

Laura Veevers-Malley

Wow. Me thinks you just saved me a whole bunch of time. I didn’t realize your patterns were fitted for a C cup. Yowzer. Worth the price of admission. Cheers!! I’ll take my measurements tonight and perhaps I can put away my FBA tools.

carol winzeler

not to be impatient, but re: the printed directions for the yoke, was there a correction made and emailed out for the installing the yoke? I no longer have the email. so far my shirt looks great!!!

Haley Glenn

Hi Carol, you can view the corrected instructions on our errata page.

sugarduck

Great tutorial! As a solid B cup, I knew that I would most likely need make some sort of adjustment to the bust, but I had no idea where to start; I’ve never had to make changes in that area before. It looks like I’ll be cutting a size 2 at the waist and hip and a size 8 at the bust, with a 1″ SBA.
Anyway, I just wanted to thank you for the straight-forward instructions and clear photos. Now I’m off to adjust my pattern…

Susan

Hi Haley! I practiced an FBA on version 1 but plan to make version 2. When I compared the pieces to see if I could trace them I realized I drew the line into the armcye too high and it went into the pleat area. I will redo this but wanted to ask where to take the line. If I take it to the notch will the pleats still lay correctly or should I go lower?
Thanks!

Haley Glenn

Slashing to below the notch should be absolutely fine. Thanks for sewing-along!

Susan

Thank you!! :)

Hi! So I need a huge SBA because my full bust and hupper bust both measure 32”
If I am right, I have to reduce the pattern by 1 and 1/2”.
I was thinking of making the version 1 with the bodice of the version 2. Do you think it is okay to do so? Many thanks

Haley Glenn

That sounds like the correct adjustment to me. Mixing and matching the version 1 sleeves with the version 2 bodice will be so cute!

Thank you Haley! I’ve just made my SBA with a 1 1/2 inch and I’ve shortened the bodice. I was wondering whether I shouldn’t shorten the back bodice as well.

laurence

hello,

I am upper bust 38,5″. Full bust42″ Waist 38″ .Hip 44″

Which size should I start with ?

Best regards.

Haley Glenn

I would recommend making a size 14 grading out to a 16 at the waist.

Laurence

Thanks for your answer.

Claire

Thank you for this!

I am new to sewing clothes for me and had always assumed I would need to do a FBA. However my measurements are:
Upper bust: 35.5
Bust: 38
Waist: 30
Hip: 38

So do I just make a straight size 10??

I wear a DD cup bra though, so am a bit confused. Any insight would be a great help!

Haley Glenn

I think a straight size 8 will fit nicely.

Bra size is typically determined by comparing your under-bust to the bust, this is why your sewing cup size might be different.

Claire

Thank you so much, but aren’t my measurements too big for an 8? According to the packet I am a 10. Sorry if this is a dumb question

Haley Glenn

I am so sorry, that was a typo on my end. What I meant to say was 10!

Toni

But, so, i made my muslin this afternoon. Our measurements match exactly , so i made a 10 and it swallowed me. i came to the site to go over fitting adjustments again.

i will do an 8 now and see what happens. While our horizontal measurements match i think it may be length that is throwing me off.

Carol Whitman

Hi, this is my first time doing a sewalong, and I’m glad I can ask questions! I’m extremely short-waisted, with full bust 39″, upper bust 36″, which makes me a Colette C cup, yes?
I really vary sizes!
Bust 39″ is between 10-12
Waist 35″ is between 12-14
Hips 39.5″ is between 8-10
Please advise! Thanks.

Haley Glenn

I recommend starting at a 12, straightening slightly below the waist line, then shortening to your preference.

Carol

Hi, I’m not sure what you mean by “straightening below the waist”. Also, don’t I need a FBA? Buttons always gape on me.

I want the length to be 3 ” shorter, so measured 1.5 ” on either side of the shorten line on the pattern, rather than taking the full 3″ above or below that line. Is this correct?
Thank you!!!

Haley Glenn

Since you are measuring at a smaller size in the hip, I was suggesting that your grade down below the waist to a small size in the hip.
Your shortening adjustment sounds correct. Thanks for sewing-along!

Carol Whitman

Hi, Do I need a FBA? Sounds like not? Will be working on my muslin as soon as family goes home on Saturday!

Haley Glenn

If there is more than a 3 inch difference between your bust and upper bust, then yes, but if not an FBA can be skipped.

Toni | archmom.com

THANK YOU!! I’ve been holding off making Aster, waiting for this SBA. Super easy and well illustrated. I was able to whip up a muslin really quick after adjusting my pattern. Now a question. The bust darts are approx 1″ below my bust. Is that how they run, due to the ease of the garment? Or is there more adjusting that needs to be done? Very excited to get going (although I did tell my hubby I wouldn’t make this until next month since we are currently in the midst of a move, ooopsie!). Thanks!

*Made a size 6 with a 1″SBA.

Toni | archmom.com

Baaahhh. Nevermind. I think I realized what I did. I needed to take a 2″ SBA. that should fix it.

Kathy Spencer

Have not sewn for ME in years. This will be my first attempt at a FBA. Your instructions look clear and I think I can follow. Plan to work on my pattern tomorrow. Thanks!

Iris

Hi, thank you so much for this – my first sew-a-long. Aster is my first attempt back at sewing after a long break and my body measurements have definitely changed. I used to be a straight B cup, but have hesitated getting back to sewing because I know I need to do a FBA.
Upper bust: 35″
Full bust: 40″
Waist: 32″
Hip: 40″
Would I cut a size 10 and do a FBA of 1.5″?
I am assuming the FBA adds an extra 1.5″ to the final waist measurement also or would I need to adjust the back for waist and hip?
Also what height is the pattern drafted for? I am 5’10” tall so will need to add length both in body and sleeves.
Thanks so much.

Haley Glenn

I recommend starting with a 10 and doing an FBA for 1.5″. The FBA will add an additional 1.5″ to the waist measurement also, but you do not need to adjust the back bodice pattern. The objective of an FBA is to add room in the front bodice for a full bust, without altering the shoulder of back bodice.

Diane

My high bust is 40″ and I am a C cup. My hips are 46″.

Looking at the finished measurements, I’m thinking size 14 should be the size I choose.

Is my reasoning correct?

Katherine

Does the FBA end up adding width to the waist and hip as well?

Haley Glenn

In the case of a relaxed garment like Aster, it does the FBA does add to the waist and hip. This is a good thing with this style of garment, otherwise pulling would occur at the placket under the bust.

Alison

Very clear tutorial — bust adjustment doesn’t look as nearly as scary now. I’m planning on making a muslin to make sure I get this right. Do I need to sew the sleeves for a muslin? Are there any other pieces I can leave out of the muslin to test the fit?

Haley Glenn

I suggest sewing sleeves in your muslin. Without sewing the sleeve it is hard to accurately determine the fit in the underarm and bust. Just remember, they don’t have to be perfectly eased and pretty. Quick in dirty is the way to go with mock-ups!

MargK

I left off the front placket (just folded back at the correct place) and put the sleeves in but did not do the cuffs (I am making long sleeve)

Karen

Thanks for this tutorial! Would you mind suggesting a size? I’m a new sewist and frustrated about fit. Everything I make ends up a bit large, particularly through the shoulders.

Upper bust is 35.5, bust is 39.5, waist is 33.5, hips are 39. And I’m quite petite at 5′.

My instinct is to make a size 8, with a FBA, and straighten the waist. Or blend sizes? What’s your opinion?

Haley Glenn

Hi Karen, I think your instinct is correct. I recommend going with the size 8, and doing a 2.5″ FBA. I don’t think your will find it necessary to straighten at the waist, since the FBA will provide extra ease in the waist.

Karen

Thanks for the help. After doing the FBA, it seems the dart is really low, so I simply cut a block out and moved it up an inch. Is this just because I’m short or does a FBA also lower the dart?

Teresa

hope it’s ok to post, I’m not formally enrolled in the sewalomg but I am following it.
My UB is 39 and FB 41.5. Using the formula I should cut a size 14 but am left with a negative amount (41.5 – 42). I’m a bit confused as to how much I should adjust, I nearly always have to do an FBA as I have a 14 F bra size. Hope this makes sense.

Haley Glenn

Try using this method to determine how much to add to the bust of your pattern. Make a muslin then slash at the bust measuring how much width and length needs to be added to the bust.

Teresa

Will do. Thanks so much for the prompt reply!

MJ

Haley, would you mind confirming if I have this correct? My high bust is 42, full bust is 44 which makes me a B cup. My waist measurement is 41 and hips are 48. So should I cut a size 18 with a SBA of 2inches? Thank you!

Haley Glenn

That sounds perfect!

MJ

Thank you! I never would have thought I’d need an SBA. So glad I am doing this sew along! I’ve read a lot about bust adjustments but never saw it so clearly explained as it is here.

Claire

Thanks Haley, for your generosity in answering so many questions!

Cindy

Hey y’all

I have to adjust 3 things my length, bust and then blending sizes (top is smaller than bottom waist hip measurements where I carry most of my weight).

Just wondering what adjustment I should do first, second and third.

Thanks

Haley Glenn

I would start by blending sizes when you cut, then full bust adjustment, then lengthen/shorten.

Karen

Shoot…another muslin will be required. I traced off the size 8, added a 1.25″ FBA…or 2.5″ total, then moved the dart up an inch.

The shoulder fits right at my shoulder. The back yoke looks good. Plenty of room in my waist and enough at hip.

But the front armhole is awful. If I close the front where buttons would be, the curve of the armhole pulls in about 3/4″ toward the center. The underarm seems a bit high, but may be ok. Hard to tell with the other arm issues. There are drag lines from underarm to bust.

Is this…
– insufficient full bust adjustment?
– using too small a size?
– need to adjust sleeve cap?

Haley Glenn

Since the drag lines are occurring on the bodice, above the point where the FBA modification was made, I think this is an indication that it is necessary to start with a larger size.

Kathy Spencer

I have my muslin except for adding sleeve. I need to raise the shoulders up by at least an inch to bring up the dart to my bust apex and to bring the bottom of the armscye up. Do I need to make the adjustment at the shoulder or slash the bodice front and shorten? I am short (5’1″ tall) and need size 16 pattern. I have this fit issue in ready to wear also. Thanks.

Haley Glenn

I suggest slashing and shortening, be sure to make this same adjustment in the sleeve also.

Diane

It sometimes takes me quite a few reads to get what it says!!!

Just confirm please, I am a C cup, so I don’t need to make a FBA? I can cut a size 14 and all I need to do is taper it to a 16 for my hips. I’ve also decided to lengthen it.

Have I made sense?

Haley Glenn

All of this is correct!

Diane

Yaay!!!!!!

Sara A.

I’m really confused. In the past I’ve sewn a 20 in the shoulders a 22 in the bust grading out to a 26 at the hips and it’s worked fine. (most recently on Seamwork Adelaide) I’m kind of butternut squash shaped: 48 upper bust, 51 full bust, 46 waist, and 57 hip. Should I be doing an SBA of 1.5″ on a 26? (48+5=53) Wouldn’t that shrink the waist and hip where I need the space? (Really it’s a belly issue. After having my daughter my belly just kinda stayed there)

Haley Glenn

An SBA does narrow the waist and hip of a garment that has no waist darts and now waist seam. For a garment the style of the Adelaide and the Aster a blend of a 20, 22, and 26, may be just the ticket. I do recommend making a muslin just to double check though!

Sara A.

Thanks, Haley! For Adelaide, I ended up grading out the hips by about an inch further at the side seams to maintain the ease and it turned out great. I love wearing that dress. I’m really debating the Aster and what view to make. I’ve got some rayon in my stash in need of a use.

Haley Glenn

Adelaide is such a great pattern, I have been wearing my version all summer. Rayon would be an amazing choice for version 3. Can’t wait to see your make!

Roberta K.

I have read through the comments and I noticed that some of the commenters mentioned that the dart was about 1″ below the bust. However I could not find an answer.

Anyway I have 2 questions:
1. Since I think the dart should point to the bust apex (I could be wrong) I moved the dart up by shortening between the dart and the bottom of the armhole. Aside from having to move the buttonholes and matching the length in the back, do I need to fix anything else?

2. Is the center front of the garment along the buttonholes or is it along the seamline to the right of the buttonholes?

Thanks in advance!

Haley Glenn

A full bust adjustment usually lowers the bust dart anywhere from 1/2 to 1 1/2 depending on how big of an adjustment was made. In many cases, this is lowering is needed for a fuller bust, but sometimes raising the dart is necessary.

Shortening between the dart and the bottom of the armhole is a good solution. Just be sure to redraw the button/buttonhole placement.

The center front is along the buttonhole placement marks.

Thanks for participating in the sewalong!

Vanessa | trucdefil.com

Hi Haley,

I just took my measurements. I generally work in cm since I’m in Europe (fortunately my tape had one side in inches! ;)
Upper bust: 32 4/8
Full bust: 34 7/8
Waist: 26 4/8
Hips: where do you take that one for a shirt (Sorry if this is a stupid question but I’m new to this)

Shall I make a size 4?

Haley Glenn

I would suggest a size 4. Regarding your hip measurement, measure at the widest part of your hip. Happy sewing!

Marsha

Hello Haley!! This is so much fun!! I made my full bust adjustment but the pattern is not quite laying flat between the armsye and the darts..

Any suggestions on how to make a lay flat? I do have a small hinge from the seam allowance to the stitching line and from the bust apex to the seamline:)

Thanks so much!!

Marsha

I meant stitching line in the last phrase:)

Haley Glenn

Make sure your are cutting a small notch through the seam allowance at the C line as specified in step 5. This helps things lay much flatter. I also find that using pattern weights to weight the pattern paper down as I tape is very helpful.

Marsha

Thanks Haley for your response. Have a great week!!

alison Low

Trying to make my second bust adjustment — the first one simply did not lay flat at the point where line B pivots to the armscye and the armscye seam allow completely tore through. How can you keep the piece flat when you cut and retape?

Haley Glenn

Make sure your are cutting a small notch through the seam allowance at the C line as specified in step 5. This helps things lay much flatter. I also find that using pattern weights to weight the pattern paper down as I tape is very helpful.

alison Low

Thanks! I tried a second time, this time with better results. I see that the armscye does not line up entirely with the original pattern piece because I made an SBA of 1/2″. Also I had to reshape the outer edge of the dart because those pieces now overlapped. Is this okay?

Agnes

I have to make an FBA with just about every top I sew and generally follow the FFRP method as shown here. But I’ve read over your section on how to pick your size several times and I’m completely confused. I’ve always selected my size by the upper bust measurement (for me, 38.5 inches) and made an FBA to create room for the full bust measurement of 44 inches, a difference of 6 inches. Your section “What Size Should I Cut?” starts out by saying “if you are making size 0-18…” I’m trying to figure out what size to cut out and this presupposes I already know that. Further confusing the issue is # 3 “The difference between your actual bust measurement and the size you are cutting is the amount your pattern will need to be adjusted. This is your bust differential measurement”. Again, I need to know what size to cut if I’m going to figure out this “bust differential”. A new term for me. The rest of the explanation is similarly unclear to me. Normally, I’d go ahead and do a standard FBA a la FFRP, but joined the sew along to get any inside tips on the best way to alter this pattern in particular. Is there any reason why I should not cut a size 10 as per your sizing, and do an FBA to add the 6 inches for my full bust? I guess that’s what you’re calling the “bust differential”. Is there something about this pattern that I’m missing that would require me to do this differently?

Haley Glenn

The FFRP technique would definitely work for Aster. Using that technique you would start with a 10 then add 6″. Using the technique that I suggested you would make a 14 then add 2″.

Agnes

Thanks for replying so promptly. Not to beat a dead horse, but why a 14? Wouldn’t the shoulders then be too big?

Haley Glenn

The theory is that using this method you can accurately match your body frame proportions to that of the size chart by determining what your measurements would be if you were a C cup. The FFRP method works really well if you are full busted and narrow shouldered.

With your upper bust measuring at 38.5″
38.5 +3= 41.5
This measurement is closest to the size 14 in Colette patterns. Opening up the bust with a 2″ bust adjustment would then accommodate a 44″ bust.
Hope this is helpful!

Diane

Thank you I’m glad this question was asked as your answer is very helpful. Answered my confusion also.

Good to learn new ideas….exciting.

Evelyn J. Gonzalez

On the bust differential calculation, are you supposed to subtract the full bust from the upper bust? Or just calculate the smaller measurement from the larger measurement? Because my full bust = 46 & my upper bust (+3) = 47, which would give a negative number of -1.

Thanks.

Haley Glenn

To calculate your bust differential subtract your upper bust measurement from your bust measurement. Since this yielded a negative number for your I would suggest using this method for calculating your how much needs to be added of subtracted from the pattern. It involves sewing a mock-up bodice then pinning or slashing at the apex to determine your bust adjustment.

Alice Elliot

I just want to say I’m so glad NOT to have to do a FBA for once!! I’m a C and my first Aster fits perfectly,

Sandy

Hi.
1. I’m still a bit confused with respect to what size to cut. My measurements are Upper bust = 40 inches, Full Bust = 45 1/2 inches; waist = 41 inches and hip = 46 inches. The difference between upper bust and full buts is 5 1/2 “. According to the chart I would take 40 + 3 to pick the pattern size (16) and then do a FBA of 1 1/2 inches to get 45 1/2” for full bust. Is this correct????

2. Also, what about the back width of the pattern? My backwidth is 16 1/2 inches – how can I tell if the back is wide encounter at the back armseye?

Haley Glenn

You would actually do a bust adjustment of 2 1/2″ to the 16, but otherwise you are totally correct!
I always like to determine any back width adjustments after making my muslin. This is because normal movements like picking something up of the ground or reaching over our heads will vary this measurement a lot.

Agnes

“The theory is that using this method you can accurately match your body frame proportions to that of the size chart by determining what your measurements would be if you were a C cup.”

OK. This is what’s confusing me. I’m not a C cup. How am I supposed to imagine what my measurements would be “if I were a C cup”? And I don’t understand the reasoing behind adding 3 inches to the upper bust measurement.

I went ahead and cut a 14 as per your suggestion, and it was much too big in the shoulders. Guess I’ll try a 12, or a 10.

Sue

Hi there. First time posting here and first time sewing a top since I was the stock size and patterns just seemed to fit!
Upper bust. 38″
Full bust. 43.5″
Waist. 37.5″
Hips. 48″
What sizes do you advise I cut please.

Haley Glenn

I would recommend cutting a size 12 and modifying with a 3.5″ (total) full bust adjustment.

This is absolutely the best explanation of FBA and SBA that i have come across! I was excited to finally do a FBA accurately! So I went through the calculations and by the numbers, I didn’t’ actually need do one, but needed to cut a sz 10 straight. So I did a quick muslin of the sz 10 and it fits so well!! With most of Colette’s other patterns, I have cut a sz 8 with FBA with success. Is fitting of Aster a little different? Just curious! I am excited to use this post a resource of other FBA I might need to do in the future. Thanks!

Hi Haley,
I’ve done a SBA and have reduced the pattern from 1 1/2” (for 3 inches).
I’ve started my muslin and my dart is too longer and too high: the edge of the dart is located after the nipple.
When I’ve done the SBA, it was not very clear for me how to redraw the dart because the lower line of the dart is now above the upper line of the dart.
How could I do to redraw the dart properly? Many thanks

Kim

Thanks for a amazing explanation of bust adjustments. I’m having an issue with my armscrye being out of whack after making my FBA. It looks very squished with an exaggerated narrow U shape. My measurements are:

Upper Bust 34.5
Full Bust 41.5
Adjusted Upper Bust 37.5 giving me a base pattern of size 10
Full Bust – Adjusted Upper Bust = 4″ for a total bust adjustment

Does this look correct? Should I redraft the armscrye to be a more normal shape. Thanks so much!

Haley Glenn

Your calculations all look correct to me. If the armscye looks very distorted redrafting below the sleeve notch to achieve a more natural curve might be necessary. Use a french curve to redraw this line, make sure that the measurement between the sleeve notch and underarm seam remains the same.

Kim

Thanks Haley,

I did redraw the armscrye and just finished my muslin. I found the dart became too large by about an inch so that has been adjusted as well. It’s a good thing too … my sleeve and back hemline now match up perfectly.

Thanks again for the fantastic explanation of FBA … it’s the first time I’ve been able to get a very nice fit with my ludicrous bust. Can’t wait to use this method on other patterns!

Annabelle

Is the armcye sewing line 5/8″? Are the normal (unless stated) seam allowances on Colette patterns 5/8″? Thank you

Haley Glenn

Yes, unless the pattern is intended for knits, then it is 3/8″.

Cathy

Hi,

Thanks for the very clear explanation of bust adjustments! My upper bust measurement is 36″, which puts me between the size 10 and 12. My full bust is 40.5″ and my waist is 35″. I’m not sure which would be better, the size 10 with an FBA, or make the 12 without any adjustment.

Haley Glenn

I would recommend a 10 with a FBA. I think this will offer a better fit in both the shoulders and the bust.

Cathy

Thanks! I was leaning that way too, I can’t wait to get started! I’m definitely doing a muslin first, it will be great to have a blouse that fits, store bought ones generally don’t.

Cathy

Karin

Hi Haley,

I have made a size 22, version 1, to the point where I sewed up the side seams. I amazingly did not have to do an FBA for the first time ever! However, the bust darts are crazy low, like maybe 2-3″ below my bust apex. I didn’t end up printing the new piece A – is the dart placement different in the new piece? If not, what’s the best way to raise the dart? It does seem like I have some extra room above the bust, and I think I need to shorten it, so can I just shorten it there? Or would it be better to just move the dart? Thank you!

Haley Glenn

The dart placement is the same on the updated pattern piece. Since you also have additional room between the bust and shoulder, I would suggest shortening between these two points. Thanks for sewing-along!

Karin

Ok thanks! I should also shorten the yoke by the same amount, right? Does that mean I might also have to change the shape of the sleeve? Or should it be fine?

Haley Glenn

Try shortening below the armscye, the only other adjustment that will be necessary is shortening the back bodice.

Deborah

I am trying to make the small bust adjustment but am confused about redrawing the dart legs. How do you know where to draw them? It seem like I have eliminated the whole dart in the process of making the SBA. Any advice is very much appreciated.

Anne-Marie

Would you help me?
My upper bust is 37,4″
My bust is 39,4″
My waist is 37,8″
My hips is 44 1/2″
Do I cut a size 12 with a SBA of 1″, and then go to size 18 for the waist and at last between 14 and 16 for the bottom?
Thank you?

Haley Glenn

Hi Anne-Marie, It sounds like you are on the right track. Those are exactly the adjustments I would make.

Anne-Marie

Ok thanks a lot!