Jigsaw Puzzle Pieces

[72begin (Bill Tumbleson)]

How would I go about separating the pieces of this simple jigsaw puzzle so the pieces could be cut out individually on my Shapeoko ?

Attached is the CarbideCreate file.

Thanks, Bill

Whale 'n Whale.c2d (84.3 KB)

[WillAdams (William Adams (Carbide 3D))]

The problem is you have open geometry (indicated by being magenta) where you need one discrete closed path for each part:

Select each set of opened paths:

and join each so that they are closed:

Then select the outline and the necessary geometry for a given part and duplicate it (control/command c):

Drag the parts out of the way to where you can work on them:

Then select the puzzle part and go into Node Edit mode:

and edit it so that it encompasses the area for the part:

right-click:

drag the new node:

Adjust the various nodes and if need be insert more:

Done

Duplicate and drag the modified geometry into alignment with the original and delete the original:

Select the modified duplicate and the duplicate of the original outline and do Boolean intersection:

Set that aside for the nonce.

Repeat for the other parts.

[Gerry]

You will need to duplicate the paths that are shared between and create closed shapes for each piece. You’d then need to move the pieces away from each other by at least the distance of the width of your endmill, and “add geometry ™” if you can’t successfully cut a profile toolpath the width of your endmill (which always works for me)

One issue you might find with this particular puzzle is the sharp points from one piece won’t have a sharp “socket” in the neighbouring piece because the end mill is round. So here:

the bit on the small whale’s tail won’t be sharper than the width of your endmill.

EDIT: or… use this pattern as it is with a laser cutter

[WillAdams (William Adams (Carbide 3D))]

Select the elements for the next part

and duplicate them:

and drag them to where they can be worked on:

Repeat the editing:

Done

Select the outline of the whale, and then shift-click on one of the edited pieces of geometry to select the later as the key object and do Boolean Subtraction:

delete the extraneous geometry and repeat:

Drag the edited geometry into alignment with the original:

[WillAdams (William Adams (Carbide 3D))]

repeat:

Drag the original geometry into alignment with the original:

and delete the unedited version:

Subtract the baby whale from the larger geometry:

and drag the puzzle piece into alignment:

[Gerry]

Will’s way is the correct way to do it in CC.

If you wanted to cheat, you could export the puzzle to an SVG. Some other tools (here inkscape) let you create a vector from a flood-fill of another shape. Basically, it traces the inside of an enclosed shape.

So you could “flood fill” each section:

and end up with this:

in about 15 seconds. It’s not quite as good as Will’s method since the fill mechanism can soften some of the corners.

But, the more tools you have to complete a job, the more … space you need for tools.

EDIT: Here’s a butchered whale as an SVG: The Butchered Whale .zip (11.9 KB)

[WillAdams (William Adams (Carbide 3D))]

Select the geometry for the next part and duplicate:

and drag off to work on it:

as before, do Boolean Intersection where appropriate:

and Boolean Subtraction where one must:

deleting left-behind geometry where necessary:

Again, Node Edit where necessary:

Where two parts interact, Boolean Union them:

then Boolean Subtract:

and as before, drag things to where they need to be and delete the unedited geometry:

Finish the remaining parts.

[72begin (Bill Tumbleson)]

Gerry:

These puzzles are for very small children so parts don’t have to fit tightly together. A photo of what I have so far is attached. The outline of the parts is done with my pen / plotter attachment using a Sharpie.
I am using a 1/16" diameter end mill to cut out the parts.

Just looking for a way to make the parts fit a ‘little’ more snugly. The other advantage is I can paint a board on both sides prior to cutting out the parts which will negate the issue of paint bleeding over the edges.

Bill

[WillAdams (William Adams (Carbide 3D))]

Hang on, I’ve got an elegant solution for the fitting once we have the idealized version of the parts.

[Gerry]

Ah… understood. If you don’t need to have such a tight fit, you could use a 1mm or 2mm endmill and just to a profile cut on all the lines, perhaps?

(I had to check the 1/16" (small imperial numbers confuse me) and it’s already in the ballpark I suggested - so ignore this comment)

[Gerry]

I made a rough version of the parts here: The Butchered Whale .zip (11.9 KB)

(edit: yes, the space after the file name is deliberate and not a Sunday afternoon mistake… )

[WillAdams (William Adams (Carbide 3D))]

The penultimate part is somewhat interesting in that one wants an intersection of two edited bits of geometry to define what should be worked with:

Then intersect again:

Then Boolean Subtract as before:

Then Node Edit:

Done

and Boolean Subtract:

and arrange:

[WillAdams (William Adams (Carbide 3D))]

The final part is more of the same:

and a final Boolean Subtraction:

but which argues for a bit of Node Editing after an Undo:

Hang on, gotta file a bug report.

[WillAdams (William Adams (Carbide 3D))]

After adjusting, Boolean Subtract:

Arrange parts:

Attached.

whale n whale parts and geometry.c2d (1.5 MB)

[WillAdams (William Adams (Carbide 3D))]

Delete the excess geometry and drag the individual parts into alignment with the original:

Inset each part by the radius of the endmill which will be used to cut them out, plus half the desired clearance:

(assuming a 1/16" endmill, that would be 0.03125" plus the clearance — we’ll use 0.0075" which halves to 0.00375 to make for a nice 0.035")

Repeat this for each part:

Then offset each to the outside by the radius of the endmill after deleting the previous iteration of unoffset parts and remove the inset parts to clean up:

Select the original outline and offset it by the half the desired clearance:

Zoom in and delete the original outline:

Group and arrange the parts as desired to cut out efficiently:

Attached.

whale n whale parts ready for toolpaths.c2d (1.3 MB)

Arranging for efficient cutting and creating toolpaths is left as an exercise for the reader.

[72begin (Bill Tumbleson)]

Gerry:

I tried the parts using your .zip file (space noted) and it worked well. As expected when I cut the parts out using a contour cut with an outside tool path I cut the gap by 50%

Now to see if I can duplicate your process in Inkscape for other puzzles.

Bill

[72begin (Bill Tumbleson)]

Will:

Thank you for taking the time to document all the steps needed to pull those puzzle pieces out as individual parts. I wound up using Gerry’s suggestion of using Inkscape which for this application produced the desired results.

If someones else needs to have greater precision your method will be here waiting for them.

Bill