How can I cut surfaces with a Brep?

Hi Grasshoppers,

I have a waffle structure system and want to cut the surfaces with a brep to get only the surfaces in the brep.

Has anyone a solution for this?

Thanks, Tanja

Attachments:

Waffel.gh, 19 KB
Waffel.3dm, 32 KB

Replies to This Discussion

Permalink Reply by nikos tzar on July 17, 2014 at 7:47am

Hi Tanja,

Here is one solution, it's not elegant, but still a solution :)

If you want to get into it more, a better organised solution would be to trim your initial lines at the box limits and offset them with the box height. This way you would have the surfaces with the proper dimensions before you create the slits.

cheers, nikos

Attachments:

Waffel.gh, 18 KB

Permalink Reply by Tanja Flower on July 17, 2014 at 8:04am

Thanks, Nikos!

But it will be better, when there is a solution to cut the surfaces after moveing them to the one and the other side because I need also a solution when the Brep isn't like a rectangle more like a triangle, trapez, pyramid, etc. The middle surfaces have to be the base but I need the other surfaces to make a 2D-Representation for the CNC-machine.

Perhaps you have an idea??

Permalink Reply by nikos tzar on July 17, 2014 at 9:23am

ok, If you want the "triming" brep to change, then the safest way to go (imo) is the Solid Intersection component. I have placed a [data dam] just before it because it is pretty slow...

hope this works out for you!

nikos

Attachments:

Waffel-2.gh, 23 KB

Permalink Reply by Tanja Flower on July 17, 2014 at 11:45pm

Thanks, Nikos! It's perfect! :)

Do you have also a solution, when the lines aren't in a rigth angel. How can I move them with a specific distance parallel? Is there any opportunity in grasshopper?

Tanja

Permalink Reply by nikos tzar on July 18, 2014 at 4:03pm

Hi Tanja,

I am afraid that the above definition will not get the job done, even with modifications.

I think it is better to decide all the requirements beforahand so that you can take them under consideration while building your definition. For example, in this case, we used the region slits component because the elements of the waffle were perpendicular. If this is not the case, then I suppose you would have to use the box slits component, and still I am not sure this would be enough.

I'll try to have a look at it tomorrow if noone else comes up with an idea.

nikos

Permalink Reply by nikos tzar on July 19, 2014 at 7:57am

ok, I believe this does it, but it is really slow. I have inserted 3 data dams before time-consuming operations, so for every change you'll have to double click on them and wait....

nikos

Attachments:

Waffel-3.gh, 22 KB

Permalink Reply by Tanja Flower on July 21, 2014 at 5:34am

Thank you very much Nikos!

It's perfect! But I think it will be better for me when I make the slits after cutting them with the brep that the slits have the same length. Do you an idea how to solve it the best?

And do you know how I can put in an expression for the width of the slits. When the lines stay vertical to eachother, they must have a width of the 'Grundplattenstärke' 0.21 + 0.01 on each side = 0.23.

But now when the lines stay in an other angle to each other the width have to be bigger. For the width I have an expression with two variables.

W=G/tan(α) +G/sin(α) +2×0,01

G stands vor the 'Grundplattenstärke'.

And α stands for the angle between the two lines.

Do you know how to put it in this system?

It would be very helpful for me.

Thanks, Tanja

Permalink Reply by nikos tzar on July 21, 2014 at 6:09am

Hi Tanja,

I am afraid this is over my abilities, so hopefully someone else might step in and provide a solution.

please note it's possible that my definition is not suitable for what you are after and should probably have to be re-written from scratch.

best of luck with your project,