Narrow Bicep Adjustment Set-in Sleeve

Narrow Bicep Adjustment Set-in Sleeve

In this post, we're going to take a look at doing a narrow bicep adjustment on a set-in sleeve. Narrow biceps are way less common than full biceps. A narrow bicep means that your bicep measurement is smaller than the pattern has been drafted for. If this is the case, you'll have extra fabric around the sleeve. Keep in mind, if you are making a bell sleeve or a relaxed pattern, this is completely normal and does not require an adjustment. Rivet has a bicep measurement on the size chart, and we also give finished bicep measurements in our patterns. We do this to give you solid numbers to base your adjustments off of. If the pattern you are working with does not include these measurements, you'll need to flat measure your sleeve piece to determine your adjustment.

To measure your bicep, make a 'Rosie the Riveter' type move and measure the fullest part of your bicep. 


If you would like to follow along with me in a video, you can do so in our Narrow Bicep on a Set-in Sleeve YouTube Video.

On the fly:

This adjustment is 100% NOT the technically correct way to do it. I probably shouldn't even mention it, but if it works for you, it works. You never want to do this a woven sleeve, and it can be hit or miss with super fitted sleeves. However, it does have its advantages when you have a small adjustment you need to do quickly. All you're going to do is gently curve a line from the under arm point to the narrowest point of the bicep. For example, if you typically make a Rivet size 10, but your bicep is in a size 8.

It looks weird and isn't correct, but it comes in handy sometimes! Now let's move on to the actual technique.

Correct Technique:

First, you're going to draw in your seam allowances all around the sleeve. You will also mark the top of the sleeve cap (if your pattern does not have a notch). Next, using your straight ruler, draw a vertical line from the notch to hem. Draw a second line horizontally across the bicep.

Now we are going to cut. Starting at the hem, cut vertically all the way up the sleeve. Stop when you get to the seam allowance. Next, cut the horizontal line from the center to the side seams, again stopping when you get to the seam allowances. To make each of these three points into hinges, cut into the seam allowances. Cut to, but not through, the seam allowances where you ended your initial cuts.

Now we've got all sorts of movement at the hinges! We're ready to make the adjustment. Gently push the bicep line inwards on each side. As you do this, the top and bottom will overlap at the bicep line. Keep the hem centers together.

Place a piece of paper behind your pattern piece, and trace around the perimeter of the sleeve. Almost there! The last step is to even out the point at the sleeve cap and the hem. Gently round out the top of the sleeve cap, and use a straight ruler to redraw the wrist line.

That's it! You're all done!

Happy Making!






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