Shoulder length intersection point



Hi, everyone. I’m trying to do the Aldrich tutorial for The Close Fitting Bodice Block and have a small problem putting in the shoulder line. The instruction says "9-11 Shoulder length measurement plus 1cm: draw back shoulder line to touch the line from 10)

Here’s a picture of what I have so far:

Is there are tool that I could use to place a point on line A10 to Ad that will enable me to draw a line from A9 to the line A10-Ad that will measure the shoulder width +1cm?

I’ve tried various tools, but none will place the point at the intersection.


How about this tool? Even description says “Special point on shoulder”.:wink:


@dismine, Thank you for your quick reply, I don’t know if I’m really out of it, but I couldn’t get that one to do the intersection point at the right place. I’ve managed to do it with this tool: I really didn’t look at that one because it seems so complicated, but it was really easy to use :slight_smile:

Now my pattern looks like this: (After putting in the darts, etc.)

Thank you very much


It is always good when you have options.


I want to perfect this tutorial so I can make a video or written tutorial for other noobies like me. I see it often in the questions.


Hello, I made a little video where you can see that using the “special point on shoulder” only works when the point is farther away from the endpoint. Lower values transform to chosen end point.


You could use Pythagorus

Z = hypotenuse = A9 to Ad = shoulder + 1

Y = known side = A to A10 = 1.5 + (armscye_depth / 5) - 0.7

X = sqrt ( (Z * Z) - (Y * Y ))

A10 to Ad = (A to A9) + X


Hi @Grace thank-you for posting this screenshot! I’ve been trawling the net for a while trying to figure out solution to shoulder length and point of intersection tool works perfectly. I’m still having difficulty mastering the shoulder point tool in context of Aldrich’s instructions on close fitting bodice. Have you had any luck?


Hi, @nottme, I’ve made a tutorial in the wiki that explains all the different tools which I think I’ve explained to death… with screenshots: And yes, I get mine right perfectly now, either with the one tool, or the other… depending on the length of my line :slight_smile:

Either the Special point on shoulder or the Point at intersection of arc and line are the tools I use.

If you have any problems, let me know & I’ll try to help.


Too good!! Will check it out. Thanks @Grace :raised_hands:


Use Point from intersect Arc and Line: Line 1st point = A Line 2nd point = A1 Arc Center = A3 Arc Radius = 5.5 (longer than hypoteneuse, so A4 is to the right of A1)

It also works where radius is less than hypoteneuse:


Thank you very much @slpencer. I think this tool would be the better one to use since it does both jobs regardless of the length of the lines :slight_smile: I’ll update the wiki tools when I get a moment.