I am blessed with chunky upper arms that almost never fit into a standard pattern sleeve. Even in knit garments, without a little adjustment I feel like Popeye, straining at the bicep seams! Lucky for me then that arm adjustments are some of the simplest to make to a pattern. In this mini tutorial we’ll cover the most common upper arm adjustments required by curvy girls.
You will need:
- Your original sleeve pattern piece
- Some tape (Magic Tape is ideal as you can write or draw over it without problem)
- Pen and pencil (I’m using a thick Sharpie for my lines so they show up on the photos – but please use something less chunky for your version so the cutting lines are accurate)
- Tracing paper or pattern tracing tissue (whichever you have to hand)
First of all, we need to quickly cover the topic of ease …
Ease is simply the difference between your body measurement and the finished garment. So, the amount of ease in your pattern is a direct correlation to the fit of the garment. Lots of ease will give you a loose fit with flowing lines, whereas small amounts of ease result in very fitted garments. Arm ease in a well-fitting garment is usually one and a half to two inches on the upper arm when sewing with woven fabric. This amount will enable you to do cartwheels and handstands without busting your seams, but note that some styles of sleeve may need a smidgen more. If you are sewing with knits you will usually find that an inch of ease in the upper arm is sufficient to comfortably strut your stuff. By the way, negative ease on a sleeve is pretty much a non-starter unless you like the feeling of being totally constricted, in which case refer to the corsets and restraints section of the Collective instead! *kidding*
First up you need to get up close and personal with your tape measure. I do this before I look at the pattern I’m making so I have a rough idea of what measurements I am aiming for. Measure around the widest part of your upper arm, not pulling too tight, but so the tape fits comfortably around and make a note of this measurement. Now measure the widest part of your pattern upper sleeve (remembering to minus the seam allowance). Compare these measurements to determine if you need to add extra ease to your pattern, remembering the basic rules of at least one inch of ease for knits and at least one and a half to two inches of ease for woven fabrics.
As I have quite chunky upper arms I normally need to add at least two inches of extra width to the sleeve piece, but I have also included instructions for three different measurement approaches below, for small adjustments of less than an inch, for fuller arm adjustments and for full arms in combination with a bigger torso. For each of the approaches you need to start with a traced version of your sleeve piece. Yes, tracing is tiresome but we are going to slash and rebuild your pattern piece so you will be glad you did, I promise.
ADDING UP TO AN INCH OF EASE
Now you have your fully traced sleeve pattern piece, draw a line right down the middle of it from the centre shoulder to the bottom, and then draw another line at 90° to the first that connects the widest part of your underarm sleeve.
Cut on the lines you have just drawn to within a quarter of an inch of the edge (this will enable you to easily spread the arm pieces we need to adjust).
After anchoring the bottom edge of the sleeve (either pin to a board or tape to the table) slowly spread apart the upper underarm edges until you have the gap in the middle you need. Don’t panic that your upper arm piece is also now overlapping your lower piece where you are spreading – that’s absolutely fine.
Once you have double checked your middle gap measurement against the extra width you need, insert a piece of tissue, either underneath or on top and tape it in place.
Now add a little extra tissue underneath your sleeve cap and redraw this top sleeve cap line to make it a smooth curve again (you may find you have a tiny dip in the middle otherwise).
Undo your anchoring from the bottom edge and now you have your adjusted sleeve piece. Yes, it really is that easy!
ADDING MORE THAN AN INCH OF EASE
If you add in more than an additional inch of width into your sleeve you’ll also need to add in some extra depth to the sleeve head to compensate. Start by tracing the existing sleeve cap of your pattern piece.
Now follow the alteration steps above, but making sure that the centre gap you leave still accommodates the extra upper arm width you need, so in my case two inches. Add in your tissue insert, go crazy with the tape and voila, one new pattern piece.
Keep the notches as per the original pattern piece you traced for matching and scrub out those on the altered pattern piece. One last thing – because we have added to the seam line on our sleeve cap with this wider adjustment we are also going to have to add some width to the matching underarm seam otherwise we won’t be able to fit the sleeve into the armhole. There are two ways you can do this; either deepen your armhole on your bodice pieces to make them larger or add in some width to the underarm side seam (I often do a combination of both).
TACKLING SHORT SLEEVES
When making the adjustment to a short sleeve, remember to tackle it as if it were a full length sleeve – this means that you will have a gap in the middle that runs the length of the shorter sleeve piece.
MAKING IT WORK
As with all pattern adjustments the only way to tell if it has actually worked is to run up a test muslin from your new pattern pieces. You may find you need to tweak the adjustments a little further – too much ease and you need to go back and spread that centre are a little less, still not enough and you may need to progress to the adjustment including the sleeve head adjustment. Sometimes, if making a really large adjustment, it also helps to add extra width to the side arms seams too.
Once you get to grips with the adjustments you need to make to a sleeve to get a great fit you’ll be amazed how quickly you can adjust all your patterns. The trick will work on any one piece sleeve you tackle.
Congratulations. You are a pattern adjusting diva with perfectly fitting sleeves. Go conquer the world.