I trace all my patterns and make any adjustments necessary to the tracing. That way, the original pattern stays intact for when I want to trace a different size or for when I learn a better method for making adjustments. Above, I re-traced the sleeve sewn into yesterday's out of print, Butterick 5678, blouse.
Based on how the sleeve hung, I thought it needed slightly more cap height - about 1/2". To start, I aligned one of the marks on the ruler with the grainline on the pattern and then drew a line across the sleeve cap at a ninety-degree angle to the grainline. I drew the line above the notches.
It's important to be able to line the cap back up correctly with the rest of the sleeve so I drew a second line across the first one as a reference point.
Then I cut apart the tissue and inserted a strip of paper equal to the width of the adjustment I wanted to make. In this case, I added 1/2". If you were decreasing the cap height, you would fold out the correct amount.
How I trace this next line is based on what I know about my shoulder which is that it is high and narrow. I rarely need extra width and often have to take width away so in my case, I use the French curve to draw a clean line to the inside blending the upper cap with the lower portion. If you had a wider upper arm, you would draw the line to the outside maintaining width. This can be significant when making a larger adjustment.
As you can see, the resulting cap is high and narrow. Typically this is the sleeve shape that fits my arm the best, allows for the greatest range of motion, and is the most flattering to my figure. This is a 3/4" length sleeve which is also my favourite length.
When I inserted the sleeve in yesterday's blouse, I had no problem easing in the fabric. I stitched two rows of basting around the sleeve cap from notch to notch and then I pinned the sleeve to the garment with the sleeve on the bottom matching the notches on the sleeve to the notches on the garment and the notch at the top of the cap to the shoulder seam. I then pulled the basting threads to gather the sleeve cap to fit the armhole working from each notch to the center point and concentrating the majority of the gathering in the upper portion of the cap where the blue line is in the illustration above.
I've found that as I work with patterns more and more, I start to recognize my shapes such as a high narrow sleeve. Often, I can tell whether a sleeve is going to work by looking at the shape and by measuring the cap height. Above, it's 8" which is 1/2" higher than the sleeve I inserted into yesterday's blouse. I don't anticipate having trouble easing this cap in and I think the slight adjustment will allow the sleeve to hang ever so slightly better. If that's the case, I will start using 8" of cap height as my criteria for adjustment.
Hope that helps. Let me know if you'd like me to clarify anything further.
Talk soon - Myrna
Grateful - compound learning
Learn from the mistakes of others. You can never live long enough to make them all yourself.
- Eleanor Roosevelt