I have the feeling the I'm asking a stupid question, but here goes.
I'm making a compound of five squares and am following the suggestions in the gallery. I've made the twelve components of that figure without difficulty, but am struggling to understand how to make the star-shaped extra parts that are described there. I have the feeling that it's some form of faceting, but doing that is still beyond me.
Extra parts for the compound of five squares
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robertw
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Re: Extra parts for the compound of five squares
Squares are flat. Do you mean the compound of 5 cubes?
https://www.software3d.com/5Cube.php
I think you are asking about the extra white parts I used to add strength inside, and help to get the last part in, as seen in image below, with description "For added strength, and keeping in mind how I will get the last piece in, I printed some extra parts for added internal strength. Here is one such part, which attaches to the part above".
I can't remember exactly how I made those parts, but here's 2 options for the main part.
(1) I think you can just use the nets of the Great Dodecahemidodecahedron (I think the dimensions match, and this is probably what I did).
(2) Otherwise, to create them from first principles, the following could be done.
Drop to 5-fold dihedral symmetry, and display the symmetry axes. Use faceting mode, and open a faceting view. Switch the main view to a stellation view as well, or use Shift+V to display stellation vertices in the base view. This is so we can click on the points that look like vertices but aren't really, where faces intersect. The facet you want to create is like below, and make sure it's near the 5-fold axis:
Accepting that facet and you should see this:
The green edges are unmatched, so we need some more faces just to make this an acceptable polyhedron. You can create triangles like below. If you have "Maintain Reflexibility" enabled, then you'll only have to draw one (otherwise two).
Now you can make this the new base model and create its nets. I found it didn't want to joint the red darts together at first, but drop to 5-fold pyramidal symmetry and then it works.
You could go to the trouble of adding more faces to cut the tip off the darts, but you can also just cut the tips off about halfway when cutting them out. Otherwise all the dart tips will meet in the centre of the model, which should work in theory, but in practice probably better if they don't.
https://www.software3d.com/5Cube.php
I think you are asking about the extra white parts I used to add strength inside, and help to get the last part in, as seen in image below, with description "For added strength, and keeping in mind how I will get the last piece in, I printed some extra parts for added internal strength. Here is one such part, which attaches to the part above".
I can't remember exactly how I made those parts, but here's 2 options for the main part.
(1) I think you can just use the nets of the Great Dodecahemidodecahedron (I think the dimensions match, and this is probably what I did).
(2) Otherwise, to create them from first principles, the following could be done.
Drop to 5-fold dihedral symmetry, and display the symmetry axes. Use faceting mode, and open a faceting view. Switch the main view to a stellation view as well, or use Shift+V to display stellation vertices in the base view. This is so we can click on the points that look like vertices but aren't really, where faces intersect. The facet you want to create is like below, and make sure it's near the 5-fold axis:
Accepting that facet and you should see this:
The green edges are unmatched, so we need some more faces just to make this an acceptable polyhedron. You can create triangles like below. If you have "Maintain Reflexibility" enabled, then you'll only have to draw one (otherwise two).
Now you can make this the new base model and create its nets. I found it didn't want to joint the red darts together at first, but drop to 5-fold pyramidal symmetry and then it works.
You could go to the trouble of adding more faces to cut the tip off the darts, but you can also just cut the tips off about halfway when cutting them out. Otherwise all the dart tips will meet in the centre of the model, which should work in theory, but in practice probably better if they don't.
Re: Extra parts for the compound of five squares
Thank you, Robert.
You're absolutely right. I should have said cubes instead of squares. That will teach me to violate my rule of never posting anything after dinner.
I'll give your suggestions a try ASAP. I particularly like the first one. I would never have thought of that approach and it shows how to address similar problems with other figures in the future.
You're absolutely right. I should have said cubes instead of squares. That will teach me to violate my rule of never posting anything after dinner.
I'll give your suggestions a try ASAP. I particularly like the first one. I would never have thought of that approach and it shows how to address similar problems with other figures in the future.
Re: Extra parts for the compound of five squares
One more question if you don't mind. How did you produce the net in your post? When I pull up W102 in Great Stella, it produces this figure and net:
I can use this of course, but the one you have makes for a neater net and less gluing. I've tried using cut/uncut, but that doesn't seem to have any effect on this net.
I can use this of course, but the one you have makes for a neater net and less gluing. I've tried using cut/uncut, but that doesn't seem to have any effect on this net.
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robertw
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Re: Extra parts for the compound of five squares
Change this setting. Because the edges coincide with another edge behind them, it is splitting the nets so that there will be tabs behind to attach internally for extra support.
