Seam allowance of sleeve cap



Here I tried to draw what a proper seam allowance of sleeve cap should look like in my opinion. Basically, it should go at 90° angle from where the top “intersection” notch is

Any idea how to make it happen in Seamly? How do you make seam allowance of this part?

I’m considering some “post-production” in Inkscape or maybe other graphics editor but still very little idea about how to make it in the most efficient way


Here is an explanation of using the McCunn method to draft a sleeve. One issue to remember, this is based on individual measurements and is not matched to any specific bodice. You may have to adjust to make it fit a specific bodice.,_McCunn_System

Here are the files used in the example McCunn-basic-sleeve-pt2.val (7.2 KB) and kim-6-29-17.vit (3.4 KB)


Sorry, I don’t see anything about seam allowances on the linked page and the file doesn’t even have details :face_with_raised_eyebrow:

I know how to construct sleeves alright, my question is about seam allowance



I tried to define what I need in “strictly geometrical” terms and that’s what I came up with. There should be a square with side=CurrentSeamAllowance that touches main outline angle and aligns with one of the sides


Hi @Krolich!
I love your question. Here are instructions (you know most of this :D) and a screenshot of the setting required.

  • In Detail mode right click on your workpiece and select Options from the picklist.
  • In the Options dialog select the Seam Allowance tab.
  • In the Node field’s picklist choose the point at the sleeve corner. In the screenshot this is p18.
  • In the Angle field’s picklist, choose ‘by second edge symmetry


Yes, it s better than “by length” but far from perfect. I guess it will have to do for now, thank you :blush:

I will have to correct this unintended “notch” so that plotter doesn’t cut off the angle.


Also this option seems to have no effect on acute angles(


sorry. I meant to continue and give information on how to add the seam allowance but the real world interfered. My husband came in and whisked me off to my morning workout. I ab happy that others were able to pick up where I left off


Here is the sleeve I drew with the detail, but also with a second detail containing a seam allowance hack. It may not be exactly what you are looking for, but I believe it shows an approach that may work McCunn-basic-sleeve-Seam-Allowance-Hack.val (15.7 KB)


This is pretty inventive! I will have to turn this idea this way and that, this implementation doesn’t seem usable with cutting plotter :thinking:

Gosh, I love this kind of technical creativity :grinning: