[WillAdams]

Thank you for that!

I am going to make a link to your comment from the forum post in question:

https://community.carbide3d.com/t/knapp-joint-with-cnc/19723 (scroll all the way to the bottom)

and will hopefully be able to translate that into Open(Python)SCAD code so as to make a generalized solution for my current project:

https://github.com/WillAdams/gcodepreview

[sebastiennight]

Hey you made my day, I can now say that I contributed to a CAD project. Had never heard of a "knapp joint" before!

OK so your bottom circles are identical, so the y-position of the center of the top circle is easy as pie.

What does your code need to do?

[WillAdams]

My pleasure! The Knapp joint is an interesting historical dead-end in woodworking joinery --- it's interesting to see it come back.

I will work up a module like to:

         def Full_Blind_Box_Joint(self, bx, by, orientation, side, width, thickness, largeVdiameter, smallDiameter, normalormirror = "Default", squaretool = 102, smallV = 390, largeV = 301):

from:

https://github.com/WillAdams/gcodepreview/blob/main/gcodepre...

(just pushed up that file, but not any other file)

The idea is that a user will be able to specify a joint dimension and position, then generate a set of DXF files, which when imported will cut out the design in question once toolpaths are assigned, no need to go through all the manual drawing.

The afore-mentioned joint, Full_Blind_Box_Joint is used in:

https://cutrocket.com/p/63781eaf9822f

and variations of it in other box designs at: https://cutrocket.com/u/WillAdams

[sebastiennight]

That's really cool, thanks!

Tangential question out of curiosity: I see several designs mention cost, eg. a "$3 box" and I assume this is just counting the cost of materials? How much does the "manufacturing" cost factor in, eg. amortizing the saws and equipment over all the stuff that you might make out of them?

Ever since I learned the math on swimming pools (which comes out at something like $400 per swim you'll have in them IIRC) I've been curious as to how wild the numbers come out to be on most of our personal projects and how economics can't be the measure for them. I'm curious if you have some thoughts on that.

[WillAdams]

The $3 Box, back when it was first made was made of 3 $1 cutting boards from the local Dollar Tree (I believe they're up to $1.25 now).

Additional expenses are of course the machine, tooling, workholding, electric to run the machine, and one's time, but for a hobbyist, amortized over a number of projects, that can be pretty minimal --- if one makes a _lot_ of projects. YMMV.