How to join 2 separate closed paths into 1 shape with overlapping anchor points

Question

I am trying to create a cut path for a CNC machine that will cut out puzzle pieces. I have the puzzle pieces overlapping each other. I am told that I need to join the puzzle pieces into 1 path.

What I have tried

1) Using Object -> Path -> Join (Command + J), but I do not notice anything different, I still have 2 separate objects with overlapping points.

2) I tried using the script "Merge Overlapping Anchors", but I do not notice anything different, I still have 2 separate objects with overlapping points.

Answer 1

As far as I could tell, this isn't possible, there's even a similar post and the solutions there are

I have a potential solution, it's going to be tedious, but it might just work.

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This assumes all your paths are relatively simple paths (puzzle pieces) - if they are rather complicated this whole thing is probably not worth it.

Also, I would recommend working in outline mode for this.

Select all your paths and use pathfinder > outline.

Then ungroup everything and select the outer paths and cut them to a new layer (Ctrl+X then Ctrl+F on new layer).

Now lock the layer which has all your loose paths, you will get back to those.

Using the Direct Selection Tool (A) carefully select the insides of the shapes and delete all of them.

Once you've done this, go to your other layer with loose paths and you can use the standard selection tool (V) to click on each of the paths on top and delete them.

After you've cleaned everything up you can select all the inner shapes and Join them (Ctrl+J)

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Your end result should be something along the lines of individual paths.

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Pathfinder doesn't do the best job and you might have to not carefully extract certain parts of the main path. (I had to in this example)

In any case, I would recommend recreating it for best accuracy.

Answer 2

"I am told that I need to join the puzzle pieces into 1 path." - that sounds like you need a combined path, not that you need to physically join or merge anything. Use Object > Compound Path > Make. It will turn the selected paths into one combined path. You will not see any visible difference, however it will show up as a compound path in the Layers panel.

I guess you should ultimately check this with your provider.

Answer 3

It appears that you are not concerned about the kerf, so I'll run with that.

The puzzle projects I've seen create a cut line horizontally to join only the "tops" of a piece, which also include the bottoms of the adjacent pieces. You would break the paths of an entire row and join only those running approximately horizontally. Once all the horizontals are completed, break and join the verticals.

The end result is a sort of graph paper with bumps, with continuous paths from top to bottom and left to right.