[Challenge] How would you build the hole pattern on the Google Nest?

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pathfinder
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[Challenge] How would you build the hole pattern on the Google Nest?

Post by pathfinder »

Hello,

This is the pattern I'm talking about:

Image

Now, the simplest but most time consuming way would be to just draw the holes in sketcher, probably in multiple sketches to keep the elements per sketch to a manageable number, but this would be just a copy. I'd rather learn how to build the pattern myself to change the parameters.


Some observations:


Holes of the same size always form a circle around the center of the pattern.

The number of holes per circle is always the same, which means you only need to sketch one "real" hole per circle and can use the circular pattern to fill in the rest.

The the size of every circle of holes changes by the same amount (i.e. circle 1 is 50mm, circle 2 is 55mm, circle 3 is 60mm and so on).

This may be wrong, but it seems like the distances of four holes in a diamond shaped pattern are always identical:

Code: Select all

   o
 /  \
o    o
 \  /
   o

Now, all of these observations are not enough to sketch the pattern as it is. I haven't figured out how to align the holes to form the guillauché style pattern and also how to determine the size of the holes relative to each other.

Maybe some of you want to weight in?
Last edited by pathfinder on Sun Dec 04, 2022 1:58 am, edited 1 time in total.
edwilliams16
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Re: [Challenge] How would you build the hole pattern on the Google Nest?

Post by edwilliams16 »

Something like this:
Screen Shot 2022-12-03 at 2.24.20 PM.png
Screen Shot 2022-12-03 at 2.24.20 PM.png (52.02 KiB) Viewed 798 times
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freedman
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Re: [Challenge] How would you build the hole pattern on the Google Nest?

Post by freedman »

Removed, problem was fixed.
Last edited by freedman on Sun Dec 04, 2022 6:46 pm, edited 1 time in total.
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pathfinder
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Re: [Challenge] How would you build the hole pattern on the Google Nest?

Post by pathfinder »

freedman wrote: Sun Dec 04, 2022 1:22 am I would probably use a hand drill and bore right thru the center where the advertising is placed...... :)
Fair enough, updated :P
edwilliams16 wrote: Sun Dec 04, 2022 12:25 am Something like this:
That looks about right, yes. I do have a hard time understanding what exactly is happening in the file, though. Am I right in assuming that the lattice(2) WB is involved?
Last edited by pathfinder on Sun Dec 04, 2022 2:05 am, edited 1 time in total.
edwilliams16
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Re: [Challenge] How would you build the hole pattern on the Google Nest?

Post by edwilliams16 »

The basic idea is in https://forum.freecadweb.org/viewtopic. ... 20#p644820
I parameterize the radii, cylinder size etc. by the ring number then make a paraseries of the rings by that parameter. I put all the driving quantities in a dynamic data object, so they wouldn't be spread all over the model. I needed to do this twice because alternate ones are offset.

EDIT I didn't attempt to exactly match and I assumed, for the sake of definiteness, that the cylinder radii were linearly increasing. If not, any formula could be accommodated. I was just demonstrating the technique.
bleber
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Re: [Challenge] How would you build the hole pattern on the Google Nest?

Post by bleber »

It appears a perfect tas for the nodes workbench.
Can you make a post.
https://forum.freecadweb.org/viewtopic. ... 1&start=70
drmacro
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Re: [Challenge] How would you build the hole pattern on the Google Nest?

Post by drmacro »

bleber wrote: Sun Dec 04, 2022 11:48 am It appears a perfect tas for the nodes workbench.
Can you make a post.
https://forum.freecadweb.org/viewtopic. ... 1&start=70
It would, but I suspect a recent change to one of the nodes has made all the examples fail.

There is no documentation for the nodes and the code has "NO BLOODY COMMENTS" :twisted: , so only the developer knows what is going on. And he has not responded for a couple days.

:(
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
mrdic
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Re: [Challenge] How would you build the hole pattern on the Google Nest?

Post by mrdic »

To me it appears the holes are distributed along an involute curve, one arm mirrored and polar arrayed. If that's so, the increase in hole size a relationship between radial distance and curve length.
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