Help with the sleeves? Not sure if they'll line up from draft

Hello world! Glad that Seamly has a nice group of forum-goers, and I’m now glad to be one of them. I’ve been having a fun time starting to pattern draft, and I LOVE the capabilities of Seamly to save and update measurements.

My question and additional information, however, is as follows: I am following the Helen Joseph-Armstrong book of pattern making for fashion design and have successfully created a basic dress block of my top. My eventual goal is to create a pattern for a leather jacket. I’ve just started the draft of the sleeve though, and it’s stumping me. How do I check if the arm will fit into the armhole of the block? What measurement do I look at?

Sorry if my work is… a mess;;; The left 2 pieces are the blocks with the additional allowances for the jacket base over them. The right is the start of the sleeve block. Does it look… correct? The length of the armhole is turning out WAY longer than the sleeve. Shouldn’t the sleeve ease be MORE than the armhole measurement??


Hello! I dash in to welcome you before someone who knows what they’re talking about arrives! So, welcome to the Seamly forums @MsFreehander!

You can look up the lengths of the various armscye curves in the Variables Table in the Measurements menu, (or ctrl-T/cmd-T on the keyboard,) under the Curve Lengths tab. Or if you mouse over the curve, a tooltip should tell you its length.

I think that @Grace sometimes makes lines of curvelength-curvelength to see the changing alignment as she shifts the curves around looking for the right spot. She should be around some time to give intelligent discourse on the drafting process, if no one beats her to it!

All I have is, “Maybe a measurement is wrong?” which I assume is not helpful. :frowning_face:



I will definitely look at that. I am still getting used to many of the controls and shortcuts, so learning a new one is a boon. That tab is much easier than the mouse-over, which I had learned but is a little wiggly as I move the mouse. Thank you!

“Maybe measurement is wrong” is definitely my thought, and would make sense given my inexperience at flat pattern drafting. Freehander is in my username for a reason, as I typically freehand patterns on myself or a mannequin, ha! The trouble is, I’ve checked all of the measurements that the book has asked me to take, and they’re accurate to me, so if there is something I’ve wildly missed or misplaced then my inexperienced eyes wouldn’t know how to check for it.

From the crtl-T I now know that the total sleeve curve is ~42.05 cm, and the total of the armhole is ~46.4 cm. That’s… too much of a different, right? They should match , or the sleeve ease should be… larger from what I understand?


Studied a bit, and found that it’s probably the cap height. This video clued me in to how things should fit in this sort of sense.

I must have picked the wrong bone in my shoulder, or picked some erroneous place to measure from. I’ve lengthened the cap height till the measurement of the curves matches more closely the measure of the arm holes. I hope that it fits properly, but only testing will tell. The sleeve should fit better now though, I hope. I’d love to know if I’m still wildly off though!


Hello & welcome @MsFreehander

Yes, the sleeve cap is always a bit finnicky until you get the hang of it. And yes, the sleeve cap needs to be slightly larger than the armhole curve measurement, otherwise it won’t fit in without gathering at the armhole, which really won’t look good.

Another thing that I’d like to mention is that it is much easier to draft all the pattern pieces on the same drafting board. This makes it easier to check things and change things as you go, rather than having to switch between drafting boards.

I always start with a basic pattern, which I edit into a coat pattern by adjusting the ease, etc.

HJA mentions in her book: Record measurements in spaces on the front and back armholes of the pattern for future reference. • Measure front bodice armhole. Record ______. • Measure back bodice armhole. Record ______. • Add Measurements together. Record ______. • Divide in half, add 1/4 inch. Record ______. Record this measurements for your model size in the space provided on the Sleeve Messurement Chart titled “Armhole measurement.”

Which you say that you have recorded correctly from the drafted front & back bodice and your bicep measurement:

And then she gives the following measurements according to the amount of ease needed in the sleeve cap to make it curve over the shoulder to your desired looseness (which normally go into a measurements file):


If you have these in the correct places, then your sleeve cap curve should be longer than your armhole curve.

Other than that, if you wish, you may send me your files and I can have a look at what isn’t matching & try to correct it for you. But without actually seeing the formulas you have used, I’m afraid I can’t say much more :slight_smile:


Screenshot 2021-01-21 214307 Screenshot 2021-01-21 214347 wird hochgeladen: Screenshot 2021-01-21 214244.jpg… Ich beziehe mich beim Arbeiten des Ärmels auf die Kurve meines Armloches. Das Bild zeigt den Bogen mit den Formeln für die hintere Armkugel.