Intersecting Voids

[studioCJF]

Can this be done? I swear I have done it before...

[Andre Carvalho]

You can have voids crossing each other to cut the same element, but you can't use a void to cut another void.

Andre Carvalho

[Gigmahabir]

Indeed, see attached.

However, if you'd like a void inside your void..just add a closed loop inside the main void while in sketch mode, as depicted in the second picture.

[studioCJF]

I was playing around with a weird shaped extrusion and tried to cut it with 2 intersecting voids. I can get each one to cut the solid but when I select the 2nd void I get the "can't keep objects joined" error (see attachment)

[Munkholm]

Cjfell

Have had the same problem recently - just for fun, I took your Void Test.rfa, extruded the unattached void to intersect with the other, and used cut geometry to make it part of your shape. That actually worked ! This makes me wonder what versions of Revit you´re using ? I´m on 2009 64 bit built.

[Gigmahabir]

I've played around with your .rfa and it's surprising, non-standard behaviour. I was able to get the two voids to cut the solid though. The attached .rfa is your plumbing family, but I think in the course of playing around that I might have not placed the void extrusion back in its precise location! It's close enough though and when you read what I did lastly I think you'll understand that I simply forgot to note its exact location.

What I did was:

- From the ref. plane plan view I moved the void extrusion out of the solid.
- I then assigned it to the ref. level workplane
- Once that was done, I moved the void extrusion as closely back to its original position as possible.
- I then adjusted the extrusion height so it would intersect the solid.
- Then, from the ref. plane plan view I selected the cut geometry tool, chose the solid, then the void extrusion.
- I then tested to make sure it worked anywhere in the solid where the void elements intersected,

[studioCJF]

Munkholm & Gigmahabir

I am using the latest (non-64 bit) version
I was eventually able to get it to work before your posts but I basically deleated and recreated and probably asigned a different work plane but not sure... I know that when I was having troubles I tried to reasign the work plane and that did not help but when I deleated and recreated I worked fine

I also always seem to have trouble creating eased/rounded edges as well... for example I make an extrusion and then would like to round the edges... I create a void/sweep with a radius edge... sometimes it works sometimes not. I have tried picking path and drawing path with equal success/non-success. It usually comes down to the alignment to the edge you are trying to cut and one of the void edges... thus it works better if they are slightly offset from each other which makes it difficult to create/specify an exact radius and frustrating at times... Does anyone have any tricks on how to do this with greater regularity/success and less trial and error? I assume there is some magic "always do this before that" or use pick-v-draw for certain types of shapes... Anyone? Anyone?

thanks

[Andre Carvalho]

I also always seem to have trouble creating eased/rounded edges as well... for example I make an extrusion and then would like to round the edges... I create a void/sweep with a radius edge... sometimes it works sometimes not. I have tried picking path and drawing path with equal success/non-success. It usually comes down to the alignment to the edge you are trying to cut and one of the void edges... thus it works better if they are slightly offset from each other which makes it difficult to create/specify an exact radius and frustrating at times... Does anyone have any tricks on how to do this with greater regularity/success and less trial and error? I assume there is some magic "always do this before that" or use pick-v-draw for certain types of shapes... Anyone? Anyone?

thanks

I think sometimes if you pick the edges of a solid to host a void that will be there to cut those edges out, you are actually cutting out what's hosting the void and therefore without its host, the void can't exist anymore... Maybe that's why you have these error messages when creating voids to cut solids or even when joining solids. And maybe that's why if you use a slight offset from the edge. I usually pick the edges I know won't be involved in the operation.

Andre Carvalho

[studioCJF]

I think sometimes if you pick the edges of a solid to host a void that will be there to cut those edges out, you are actually cutting out what's hosting the void and therefore without its host, the void can't exist anymore...

Andre that's my assumption as well... I just had an idea that i will try later... It involves drawing reference lines with "pick / offset" to duplicate the intended path with an offset and use that as the Sweep/Extrusion path. This may be a "DUH" moment for others but I have not seen this idea referenced before. I guess this is one of those "Forget what you know and start thinking like Revit" ideas... I'll let you know if it works

[Gigmahabir]

I tried this method in the file I posted above to no avail. I think the modeling method is the fork in the road so to speak. There might be more than one method that will get the outcome you need, if one is making you ornery, try the other!