Hi,

I am new to Inkscape.

I am using it to draw sewing patterns. Something like this:



The blue line is where to cut the fabric (by CNC laser, later). The dotted red line is where to sew. The Vs in the hem line are for alignment purposes when sewing.

I have done this by creating a closed path in the red shape, Copying in place, applying a dynamic offset, applying a spaced triangular pattern along the path and a difference to create the alignment nicks.

This is close to what I want but not quite.

I want to treat each edge separately, so that the first V on each edge is at the start of the hem. (when sewing each edge will align with a different other piece).

So, I think that the offset blue line needs to be three separate paths.

However if i split the closed path into three open paths and apply an offset to each open line, I get a line on BOTH sides. I can't work out how to delete the offset on the side that I don't want.

Any suggestions?

Andrew

Hi!

After the dynamic offset, convert the objects to paths (Ctrl+Shift+C),
use the node editor tool to unconnect segments next to the wanted part,
then break it apart (Ctrl+Shift+K), and delete the unwanted paths to have the right part.

Good luck!

Hi.

An alternative to breaking the linked offset path might be to use the path effect editor.

Make your linked path as usual.
Convert the linked offset to a path.Ctrl Shift C
Draw a "Alignment notch pattern" as in example below.
Use F1 to go into "object select mode" - select the "Alignment notch pattern" - press.Ctrl C to copy to clipboard.

Select the linked offset path
invoke the path effect editor - Shift Ctrl 7
Click the plus sign and select pattern along path
Click the clipboard icon.
Result:



Path Effect Settings:


You might want to alter the size of the "Alignment notch pattern" depending on the scale of your drawing.
(If you flip the "Alignment notch pattern" horizontally you will not need the Width = "-1" in the Path effect dialog.)

Some links you might find interesting:
http://www.sew-brilliant.org/2010/08/29/manually-added-seam-allowance/
http://www.burdastyle.com/search?key=pdf+pattern
http://www.taumeta.org/?cat=13

Good Luck!
RGDS
Ragnar

Hi.

The method in last post does not "align" the "Alignment Notch pattern" properly when adding the pattern to two different pieces of "fabric".

To get the patterns to align:
Duplicate the path (here the "S" shaped curve)

Use the "Double Alignment Notch" and apply the Path Effect as before.
Convert the offset path to a path. Split the ends and combine with the "rest of the fabric".

Result:
( Here the notches has been added to one seam only due to 'laziness' )


If a more "cookbook type" explanation is needed - chime back!

Good Luck
RGDS
Ragnar

Many thanks for the help.

The big clue I was missing (and that everyone pointed out in passing) was that a linked offser is not a path in it's own right. Once it is converted to a path, everything I need becomes possible.

Again, many thanks.

Andrew