Well, I think this quote pretty much sums up drafting and fitting sleeves! I am sure you agree. Once you start, you have no choice but to keep going!
I started the journey by drafting the Straight Sleeve in "Dress Pattern Designing" by Natalie Bray. I chose it because it is the only sleeve I have found that appears to have the correct sleeve head shape required for an actual arm. Here is my draft:
It looks pretty promising doesn't it? The cap height, the curve lines, all appears in good shape. Well, after what I thought would be a quick draft and a few fitting adjustments, a full day later, I ended up with this on my table:
Here is the very first sleeve fitting:
All the arrows are showing the drag lines indicating poor fit. The grain line of the sleeve is not lined up with the center arm and the bicep line is curving upward. All in all not good! My goal now is to alter the pattern to eliminate all these issues. This is when I thought: "Do I really need sleeves for this dress?" But I persevered and after many pattern adjustments, I managed to make it work. You can see that the grain line is now following the center of the arm, the bicep line is much more level, and the drag lines are gone.
You are probably wondering what I did to achieve this and why it took me so long to work it out. The reason it took me so long was because I misdiagnosed the fitting issue to begin with. I thought that there was a cap height problem. In the image below, the green sleeve is my first pattern, the blue sleeve is my last pattern, all the dotted lines in between represent the progress of each pattern correction.
You can see, in fact, that the last sleeve (blue and better fitting) is actually a slightly shorter sleeve cap than the first one (green). The biggest difference between the first pattern and the last pattern is that there is a shift in the sleeve head shape toward the front which accommodates the prominent front shoulder bone. So it was actually this issue that was creating all the drag lines, not the cap height. Granted, I probably could use a little more cap height on my final sleeve for a perfectly horizontal bicep line, but I think this slight hiking will give a bit more flexibility for upward and forward arm movement. (Or am I just tired of fixing this sleeve?)
In any case, I wanted to share this learning experience with you in the hope it might help you in a similar situation. I know I definitely won't make this mistake again and since I persevered, I now have a good fitting sleeve for any new pattern I make. I made it through sleeve pattern hell!