pattern of hexagons on cylinder

Post here for help on using FreeCAD's graphical user interface (GUI).
Forum rules
and Helpful information
IMPORTANT: Please click here and read this first, before asking for help

Also, be nice to others! Read the FreeCAD code of conduct!
User avatar
DeepSOIC
Posts: 6528
Joined: Fri Aug 29, 2014 12:45 am
Location: Saint-Petersburg, Russia

Re: pattern of hexagons on cylinder

Postby DeepSOIC » Sun Aug 21, 2016 9:01 pm

NormandC wrote:MODS: would it be possible to split this talk on repeating hexagons into a new topic? I figure it could be split starting from this post: viewtopic.php?f=3&t=13405#p134659
Done. ;)
User avatar
NormandC
Posts: 18534
Joined: Sat Feb 06, 2010 9:52 pm
Location: Québec, Canada

Re: pattern of hexagons on cylinder

Postby NormandC » Sun Aug 21, 2016 10:07 pm

Thanks DeepSOIC! :D



This is an example of use of Draft Array to produce an honeycomb pattern from a minimal sketch with just 24 constraints.
FC_honeycomb_pattern_01.png
FC_honeycomb_pattern_01.png (15.21 KiB) Viewed 357 times
The single dimensional constraint is controlled by a Spreadsheet.
FC_honeycomb_pattern_02.png
FC_honeycomb_pattern_02.png (15.13 KiB) Viewed 357 times
Draft Array can create a very efficient and almost limitless pattern. The Spreadsheet's B2 and B3 fields are used for the Array Interval X and Interval Y values.
FC_honeycomb_pattern_03.png
FC_honeycomb_pattern_03.png (11.18 KiB) Viewed 357 times
ehrichweiss wrote:When you look at how a honeycomb pattern is created, There are no horizontal or vertical breaks/spaces in the pattern where one can cut those cells out with a straight line. See the image below. There's not really a good way to cut the pattern without cutting 50% of the cells in half
Agreed, but you can create a second Array with just a line to close the open cells at the ends of the pattern.

Now I know my example cannot be extruded (just like your image BTW), but it would be an easy matter to modify the sketch so it does.

As for creating a honeycomb pattern wrapped around a cylinder, FreeCAD is missing the tool for that (wrapping a sketch on a surface). But a macro that does was created and modified by a few users here: viewtopic.php?f=8&t=14710#p131777

With this macro, you could create a sketch containing a single hexagon, execute the macro to generate a wrapped and thickened to solid hexagon, create a draft array, then use the array to cut a cylinder.
Attachments
Honeycomb_pattern_normandc1.fcstd
(89.83 KiB) Downloaded 47 times