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)
- Scissors
- 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.
Mehitabel says
Hi, I wonder if you could advise? I need to widen a two-part tailored jacket sleeve in the bicep. I’m familiar and comfortable with making the adjustment on a one-piece sleeve. I’ve thought about cutting the under-sleeve in half, adding each half to each side of the upper sleeve, making the adjustment, then putting the under-sleeve back together again. But the thing that frustrates are the beautiful curved seams for the tailored sleeve.
Ender Xenocide says
Well, I added 2″ in length (yay being tall) and 2″ in width to my sleeve piece. I’m just a little confused by the “deepening the arm curve” solution for making the new sleeve match up with the garment body. Could you please explain this a little further?
Laura Krier says
Alas, I’m super confused by the paragraph for adding more than an inch of ease that begins with “Keep the notches as per the original pattern.” I’m not sure how to line up the new, wider sleeve pattern with the original sleeve cap pattern. How do you determine what the new sleeve cap measurement should be?
Pamela says
This is awesome!! I can hardly wait to try this out. I’ve not sewn as much for myself since getting a bit rounder. I swear I gain weight only in my arms and waist. This is going to be a game changer for me. Thanks.
Liz says
Thank you for this, I have so many sleeveless dresses I’ve sewn because of not being able to get those damn sleeves to fit.
I know it seems kinda redundant to add a link to another way to do this, but I do like this method to change sleeve bits – though in the shirt I made bigger it was the right size in the bicep but too big in the rest of my arm, so take this with a pinch of salt:
https://www.youtube.com/watch?v=-c6JrVlwp2I
Oh, and I loved written/pictures instructions over videos 🙂
msknitsew says
Thank you so much for this tutorial. This is my number 1 fitting issue. I’m going to try it.
T says
Do let us know how you get on with your alterations. Happy sewing!
Jan says
As a beginning seamstress, this is really helpful! Thanks for the tutorial, says the curvy chick with the chubby arms flapping in the breeze….
T says
Hey Jan,
So pleased to hear you found the tutorial helpful. As a fellow chubby armed sister I have to say when I cracked the sleeve adjustment code it reinvigorated my sewing as everything fit me so much better!
knitmo says
I have muscular arms — thanks to farm life of throwing bales etc — so I have to modify sleeves significantly. The 2 1/2 -3 inch adjustment for the bicep worked, sort of, but I was never satisfied with the limited range of motion I was left with. I had never realized that large of an adjustment flattened the sleeve cap significantly, thus making it difficult to move in. This tutorial was a stroke of brilliance for me.
Is there a rule of thumb, or best guessing practice to help determine how much to lengthen the cap?
I would assume you’d figure how much to lengthen the arm scythe by measuring the curve of the cap and comparing it to the arm scythe.
Margaret C says
Great tut!!! And I second the appeal for the sleeve on a sleeveless pattern tutorial- that would be amazing!!
One thing I’d like to add from my experience is that not all arms are symmetrical. I need to add very little to the front half of my arm, but quite a bit to the back on patterns. As you said, you need to do muslins (I think I did about 6 before I was happy!)
How that helps someone else – or maybe I just have very weird arms??!!
T says
Hi Margaret,
You’re absolutely right, not everyone’s arms are symmetrical which is why making the muslins and tweaking further is the only way to get a great result. I’m pretty lucky as on most garments this adjustment works fine, but on fitted jackets it can be much more painstaking! We will definitely be tackling a tutorial on adding sleeves to sleeveless garment so watch this space!
J K says
Helpful post!!
As a follow up – could you or one of the other contributors write a post about how to insert a sleeve into a pattern that is sleeveless?
With my ample upper arm, I don’t like to wear sleeveless dresses except when lounging at home. I often find sleeveless tops and dresses I would love to wear if I could add a sleeve.
Thanks so much!!!
T says
Hello JK,
What a great idea for a follow up tutorial. I’ll post it onto our to write list of future blog topics.
Jeri Sullivan says
This is always the hardest part of grading a pattern for me. It often gets so frustrating that I simply opt for sleeveless versions. Thanks for providing multiple options and clearly walking through the steps. Seems pretty simple the way you explain it!
T says
Hi Jeri,
Glad you found it so helpful, and yes, it’s so simple when you know how isn’t it! It made a world of difference to my sewing once I figured it out.
Kat says
I’ve been struggling with this modification for a while now and you’ve just solved all my issues! I could wrap my chunky upper arms around you in a hug for writing this!
T says
Thanks for the hug Kat! Chunky armed sewers of the world unite! 😉