How to alter this pattern for a large bust. - Sewing Machines

Measure fullest part of the bust. Pivoting the pattern is a good system.

Size chart measuring

How To Increase The Bustline In Commercial Pattern

Beginner Guide to Sewing Ep 20 Bust Adjustments

New Take on the Full Bust Adjustment

Lots of online information.

You need to study how to alter a pattern to fit your measurements. Most often, it is recommended to purchase a pattern to fit the bust and then alter the others to fit. You can go to the library and check out some pattern fitting books.

The best thing is to purchase some inexpensive fabric, ie muslin, and use it to make a trial garment. Making a trial garment will help you fit it to your body plus you don't waste your nice fabric on something that won't fit.

The Merits of Basic Fitting Pattern Threads

Adjusting Patterns for Fit part 1 The Sewing Geek

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This may help:

Is there an easy way to alter the size of Cross Stitch Pattern

How to Increase and Decrease Your Stitch and Cloth Size

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here are some more places to look

Full Bust Alterations or Adjustments FBA Sew Mama Sew Outstanding sewing...

Idle Fancy Sewing the Curve Princess Seam FBA for Large Busts



Enlightenment The Full Bust Adjustment

Gertie New Blog for Better Sewing Dealing with Pattern Ease

This is a bit complicate. the reason the pattern pieces are different in length is because the front is usually longer because on a woman, there is the bust area to consider. This make the front longer to accommodate that extra fullness.
If you do not have a bust area then why not just use two back patterns? Hope this helps.

try here
http://www.sovintagepatterns.com/1950s-Flirty-Blouse-Pattern-Simplicity-4645-Vintage-Sewing-Pattern-2-Styles-Low-V-Back-Bias-Roll-Collar-Simple-To-Make-Bust-34-Vintage-Sewing-Pattern-FACTORY-FOLDED_p_5766.html
(not the right size ??)

or here
http://www.artfire.com/ext/shop/product_view/9606279
(not the right size again ?)

usually the pattern is altered below the armpit area. Lengthening requires either tracing the piece and adding additional length by sliding the pattern piece the required amount. OR but cutting and adding in a piece of paper and retracing the cut lines.

This question doesn't really belong here... you need to go to a tailoring site. ;) I can suggest http://www.patternreview.com join and you will get lots of help from the forum pay a member fee and get online classes.

is this a fitting problem with the pattern? or do you mean that the seam is pulling up?

If the sleeve pattern is too small, then you may need to alter it.

There are lots of books on altering to fit you, Palmer Pletch write several and you should be able to find these in the library. But put simply, you need to add some more fabric in to the back of the sleeve if its too tight in the top of the shoulder and the easiest way is usually to "slash and spread " the pattern piece, then paste this new shape down over a sheet of paper and remark the outside cutting edge. Remember, if you add in an inch in the back of the sleeve piece, you will need to add an equal or similar amount into the back of the shoulder where the sleeve fits in to match.

Used stabiliser under fabric