Hi,
I'm kinda new to Inkscape, but as I mostly use it for laser cutting, there is one major thing that's been bugging me:
How do I "extrude" or "extend" a rectangle so that I am able to make a finger / box joint?
Here's an example of the kind of thing I'm after:


The only way I've found to do this is by editing the paths directly. However, this is very finicky and the laser software seems to ignore my path edits when merging rectangles. Does Inkscape have a tool for this built-in or is there a technique that I could use?
Thanks, Gary

Try the Extrude extension. It's available in Extensions -> Generate from path -> Extrude.

You will need two copies of the object you want to be extruded, one in each 'end position'.

This will also produce a lot of paths that you will not need. These will normally be hidden behind the fill color of the object, so if you make your originals white, then you might not see them. Else you may have to remove them manually.

Sorry, this doesn't seem to work. All it seems to do is take all of the line endpoints and connect them with all of the other selected line endpoints. I realize that my example picture wasn't the best so here's a better one:


I was able to do this with an extension that makes tabbed boxes, however I would like to know how to do it by hand because for my purpose I want more control over the tabs.

Use path editing, in conjunction with snapping to grid for exactness.
Add a grid in the Document Properties (File -> Document properties).
Convert rectangle to path.
Double click on the line to add nodes, set snap settings like this (you'll need one more node than I have in the screenshot, one that stays on the perpendicular line, but you can move and snap that, too):


Or if you don't care about exact measurements, you can just spread the nodes evenly. Select them with the node tool and use the 'Align and Distribute' dialog to do so.

gary600 wrote: However, this is very finicky and the laser software seems to ignore my path edits when merging rectangles. Does Inkscape have a tool for this built-in or is there a technique that I could use?
Thanks, Gary

As you have noticed there is a tradeoff between having control and how quickly something can be done. I am interested in the 'ignoring of merged rectangles.' are you saying that even after you do a union your laser device does not see the new shape?
I would probably approach this by using one large rectangle and several identical small rectangles spaced and aligned along the edge of the large one using the align and distribute dialog. once they are in position selecting all and doing a union would give me what I think you are trying to get. There's no node editing involved in this method, which would perhaps not be the best tool to get precisely the same size of tab. Using duplicates of rctangles as I have described above achieves this easily.