Oya,

calling for help. I have a basic form with sharp angles. Let's say an X. Offset by 2mm. Extrude to come up with something like a cookie-cutter.

But how can I make a cutting edge ? I totally understand (do I?) the problem of intersecting curves, so I am not at all calling this a bug of any form. I also understand why a Sweep won't do it, basically for the same reason if I am not wrong.

It am at a loss how to get this done. I thought about extruding "walls", chamfering them and then bool'eing them until a nervous breakdown. Maybe I must. Or maybe there is a better way ?

If anybody has ideas, I am all ears !

Hi Ditto, you seem to have already created the cookie cutter. I'm not understanding what else you want to do to it.

> But how can I make a cutting edge ?

This is the part that I'm not understanding. You can make a cutting edge for example by drawing a line in the front view and then use boolean difference to cut your X with it like this:





I'll need some more information or description about what type of shape you want to be able to help.

- Michael

A cookie-cutter has a sharp edge, to cut the cookie dough. (In memory of Mother.)

Draw a short line segment PERPENDICULAR to the two X curves, from the bottom inside corner, down to the outer curve, in a Green style (3D view is good for this).
In the Right View, highlight the green line segment, and draw a Red style polyline triangle downward, to a point.

In 3D view, sweep the triangle along the two X curves.
Boolean the two solids.

https://imgbox.com/YcwIEReg

The outer size of the Cookie is the "medial axis" of the Bottom View face of the X.

- Brian

Alternatively, the triangle could be internal to (a greater z height) X...

Of course, the cookies will then have a chamfered outer edge.
My memory of actual cookie cutters, is a thin band of metal, (possibly stamped), which is thin enough to count as a moderately sharp edge.
They had some sort of handle.

With another X design, it was necessary to move the line segment (and triangle), to the middle of one leg of the two curves, in order for sweep to work properly.

- Brian

Hi Brian, yeah I think you understood it better than me re: cutting edge.

If you want something like thin metal, you can select the bottom face and use Construct > Offset > Shell:





or maybe like this, here with another offset to make a middle piece, move that in Z and then Construct > Loft between the 3 profiles using Loft style = Straight.









- Michael

Hi Michael,

Cool techniques your are showing!

I particularly like your Shell design. It seems more "historical memory" correct, IMHO.

- Brian

If these are for a Twitter party, perhaps one half should be broader...
- Brian

Many thanks! I am light-years away from knowing what I do, that's a painful insight. ;(

Btw, nothing to do with Twitter or X, just an extreme form with many sharp angles,

Ok, to work now. My wife is preparing Christmas, not.

Thanks again !

Hi,

Sweep (two rails) is a good and easy way for me.
Profile is the red polyline and rails are the magenta polylines.

You can chose the profile too...
Because the printability could have be done by a minimum of material.



If the shape of your cookie cutter is less simple, you can rebuild the shape to have something softer.
Cookies don't need a millimetric precision.

You could cheat a little.
Select just a face and extrude-tapered. A "Perfect point" will fail and disappear, but you can zoom in and stop just before it is a perfect point.

In real life there is no such thing as a perfect point.

Then you can separate all the pieces and show points and just grab and stretch the bottom points down for as tall of an extrusion as you need.

Here's another way to do it as well.

Maybe advantageous to have a straight cutting edge inside the cookie cutter ?

I like this one vic

And then the machine mechanism would have a little “pimp walk” on the way up… seperation!