50 Digital Joints - The Board Corner Joint FeatureScript

Aaron_Hoover

Hi Folks, 

I just finished version 0.1 of the Board Corner Joint from the 50 Digital Joints collection. This is the one that creates finger or box joints similar to what you can make with @lemon1324's Laser Joint. With this joint you can also make so-called fingertip joints (finger thickness = cutter diameter) and hidden or lapped versions of the above. My favorite, though, has to be the "Hammer Tenons" (and lapped hammer tenons) joint that's sort of a 1st order piecewise linear approximation of dovetails (or blind dovetails in the lapped case). 

Thanks to the example provided in the Laser Joint FeatureScript, this joint also includes the ability to add an "allowance" to the joint and mating faces. In fact, now that I've seen how useful that can be for manufacturing, I think I'll go back and add it to the Frame Corner Joint as well. Despite my earlier protestations, it really is a whole lot easier to go directly from the model to the machine without mucking about with cutter diameter or "stock to leave" parameters in CAM. I'm a convert. 

Finally, many thanks to @lemon1324 for being okay with me blatantly copying code from his excellent Laser Joint. 

Please check out the FeatureScript - https://cad.onshape.com/documents/efc963b657ec24bd8613fb51/w/bf1637267a4c6b634008215b/e/daec011899356d6d6cfceaa4 - and let me know if you have any feedback. 

Aaron

Aaron_Hoover

Hi (again) Folks, 

I wrote a short blog post about the Board Corner Joint in case anyone is interested in checking it out: http://amhoov.org/2019/02/14/digital-joinery-part-2-the-board-corner-joint/. 

Thanks again to everyone who's been helping to answer my questions and provide suggestions on this project - @ilya_baran, @konstantin_shiriazdanov, @NeilCooke, @Jake_Rosenfeld! And, big thanks to @lemon1324 for allowing me to crib so much from the Laser Joint. 

lemon1324

One note is that on the hammer-tenon joint, you're currently applying corner overcuts to interior corners parallel to the machining axis, but since one of the edges doesn't go all the way through the part, the geometry currently requires two ops to machine:Maybe extend these overcuts up to the top surface so they can be machined through? (and more generally extend all overcuts up to one of the two faces to make things machinable in one op)

Aaron_Hoover

Nice catch. I didn't notice when I machined this since I selected the bottom contour for the profile cut (which automatically propagated the overcut up to the top surface). 

I suppose I'll query for edges that have vertices coincident with the bottom face and place the other cylinder endpoint at the same height as the top face. 

david_parker441

Hi Aaron,

I must be doing something wrong here, I built 2 parts just like in your blog post but just can't seem to get the feature to work.  I got Laser Joint to work just fine - I must be missing something.  Can you please look at my workspace and tell me what I'm missing?

https://cad.onshape.com/documents/c7d35f0a39a0147dcd4e9dc0/w/c08082e35c7f2f9a4fa4c652/e/f4a848fca49d47960e9a8fcd

Thanks,
David

david_parker441

OK, no worries - I had my sketches and extrusions lapped the wrong way.  It's really fun - thanks!

Aaron_Hoover

Hi David, 

I'm glad you got everything figured out. Thanks for trying out the feature. Let me know if you run into any more weirdness or have suggestions for how it can be improved.

Cheers,
Aaron

LaamuTeunis

Thanks for Aaron_Hoover!
This is very usefull featurescript.