topic Re: Nested void family not cutting in Revit Architecture Forum

Nested void family not cutting

vincent6062 — Fri, 11 Sep 2015 08:08:50 GMT

Hi All,

I would like to create a void in a generic model family (B) to cut solid geometry in another generic model family (A). Even though I turned "cut with void when loaded" in (B) and loaded it in (A), it seems impossible to select the void with the cut tool.

Is there something that I did not do correctly or is this simply impossible ?

Thank you in advance for your reply.

Kind regards,

Vincent

Re: Nested void family not cutting

dzanta — Fri, 11 Sep 2015 13:43:27 GMT

why not create the void within the family that needs to be cut?

Re: Nested void family not cutting

dzanta — Fri, 11 Sep 2015 13:49:18 GMT

a family that has a nothing but a void in it is seen as "invisible" in another family or a project. This is why you cannot use Cut Geometry to do what you want.

Easiest thing to do is create the void within the solid family and then you can use the Cut Geometry tool to make the solid family having a void cutting it.

Re: Nested void family not cutting

cbcarch — Fri, 11 Sep 2015 13:49:43 GMT

Make sure you use Cut Geometry in the family containing the Void. Then reload into other family. Then reload into project.

Re: Nested void family not cutting

ToanDN — Sat, 12 Sep 2015 00:30:14 GMT

Try a face based void family. Remember to use the void to cut the solid first before loading it into the other family.

Re: Nested void family not cutting

vincent6062 — Wed, 16 Sep 2015 00:12:30 GMT

Hi Dzanta, it is because I wanted to repeat the void a great number of times and also allow flexibility if I wanted to modify the void form later on.

Re: Nested void family not cutting

vincent6062 — Wed, 16 Sep 2015 00:20:03 GMT

Hi cbcarch,
what do you mean by using the cut geometry in the family containing the void? If the family contains only a void I do not see with what I could use the cut geometry.
Many thanks,
Vincent

Re: Nested void family not cutting

mattendler — Wed, 16 Sep 2015 01:24:01 GMT

If you want to make a family that is made up of only void geometry, as in a face-based hole or pocket, you must create model line geometry that overlays the newly created edges of the void.

Best example is making a parametric hole family:

1. Create new face-based generic

2. Create model line

2a. Draw circle on default face

3. dimension the circle's diameter

3a. parameterize the dimension with an instance parameter

4. create a void extrusion

4a. pick lines and lock to the model line circle

4b. use the cut command to cut the face

4c. in properties, click cut void on loading

now load this into any family with an extrusion and it should auto-cut your extrusion.

Re: Nested void family not cutting

ToanDN — Wed, 16 Sep 2015 20:06:15 GMT

If the void is a face based family, you don't need to add any model line. See attached.

Re: Nested void family not cutting

BIM.Champ — Wed, 11 Jan 2017 04:18:34 GMT

I had the very same problem, unable to get a nested family void to cut a solid in the host family.

My solution:

Face based nested family with voids

When loading the nested family as a component, choose a 3D view and make sure you host it to the face of the solid. I found this to do the trick. (It then associates and voids within the nested family with the hosted object)

Prior to this i was hosting to a reference plane, and it wasn't cutting voids.

Hope this helps

Re: Nested void family not cutting

ToanDN — Wed, 11 Jan 2017 05:30:41 GMT

Thanks for clarifying your workflow. But I didn't think I had any problems cutting things with voids 🙂

@BIM.Champ wrote:

I had the very same problem, unable to get a nested family void to cut a solid in the host family.

My solution:

Face based nested family with voids

When loading the nested family as a component, choose a 3D view and make sure you host it to the face of the solid. I found this to do the trick. (It then associates and voids within the nested family with the hosted object)

Prior to this i was hosting to a reference plane, and it wasn't cutting voids.

Hope this helps

@ToanDN wrote:

If the void is a face based family, you don't need to add any model line. See attached.

@ToanDN wrote:

Try a face based void family. Remember to use the void to cut the solid first before loading it into the other family.

Re: Nested void family not cutting

Alfredo_Medina — Wed, 11 Jan 2017 20:04:07 GMT

Steps # 2, 4a, and 4c are not necessary.

Re: Nested void family not cutting

DanielLemen — Fri, 11 Aug 2017 12:53:05 GMT

I've tryed to work this out. but no.. Have you missed something, shoulden't it be "Cut with Voids When Loaded"? Or please make an object so I can see.. or maybe I misinterpreted this topic. But I would like to have a family that could cut into my other family. What am I doing wrong?

Re: Nested void family not cutting

ToanDN — Fri, 11 Aug 2017 18:04:54 GMT

There are several unnecessary steps in the Solution. Please watch the screencast for a simple demonstration.

Re: Nested void family not cutting

timwaldock5907 — Fri, 10 Nov 2017 06:44:10 GMT

It seems that no one has really answered the original question:

"I would like to create a void in a generic model family (B) to cut solid geometry in another generic model family (A). Even though I turned "cut with void when loaded" in (B) and loaded it in (A), it seems impossible to select the void with the cut tool."

A few versions ago, when Autodesk gave us the property "cut with void when loaded", it gave us the ability to use a void in a family to cut another family without having to make the cutting family face-based. This was a very useful new feature because it is not always appropriate to make the family face-based (for many good reasons, not for discussion here). However, there were a few limitations:

It only worked with certain category combinations (Casework and Generic being among them)
It only worked in the project environment, not in a nested family situation - as requested by Vincent

The suggested solutions involved using a face-based family - which I don't want to use. Has anyone found a way around the nested-family limitation to make it work in the family editor? I even tried making both nested families shared, to see if they would cut each other when the parent family is loaded into a project - no go.

Re: Nested void family not cutting

ToanDN — Fri, 10 Nov 2017 07:05:09 GMT

@timwaldock5907 wrote:

Has anyone found a way around the nested-family limitation to make it work in the family editor? I even tried making both nested families shared, to see if they would cut each other when the parent family is loaded into a project - no go.

Of course, one way around is using a face based void family, which you don't like for reason unknown. Another way around is create the void directly in the main family.

Re: Nested void family not cutting

timwaldock5907 — Fri, 10 Nov 2017 07:21:53 GMT

Unfortunately neither of those solutions will work in this situation:

The parent family is a kitchen layout (one of many variations); It has lots of standard casework families assembled into it - these include benchtops, which may or may not have sinks placed on them. When a sink family is placed, it may or may not be located in conjunction with a benchtop - if it is, then it needs to be able to cut a hole in a benchtop. So the sink must be a separate family. If you make the sink face-based, it really restricts how you can use it: ie, it can only be placed and hosted on a benchtop; it cannot be wall-hosted (not that I advocate that method, for other reasons); it cannot be free-standing, it cannot be workplane hosted (which would allow a mounting height property that can be manipulated or recorded); face-based families have to be defined in very specific ways, and cannot easily be converted to non-hosted; placement of face-based families is inconsistent with non-hosted familes, etc - this list goes on . . .

This method works just fine if you assemble the families directly in a project, and cut them there - but not as nested components in the family environment.

Re: Nested void family not cutting

ToanDN — Fri, 10 Nov 2017 07:37:29 GMT

Please see attached. A face based family can placed on faces, on reference planes, or on nothing. There is no limitation.

Re: Nested void family not cutting

timwaldock5907 — Fri, 10 Nov 2017 09:21:33 GMT

Thanks for trying to help with this - I really appreciate it. Face-based families do have some advantages, and yes indeed they can be placed on a workplane as you kindly demonstrated. However, they do actually have many other limitations - not least being that they will only cut an element if you host it on the element, which is not what I want. This discussion is going off at a tangent - all I really want to know is whether anyone has solved the limitations where the family (with void) is not face-based.

Re: Nested void family not cutting

ToanDN — Fri, 10 Nov 2017 18:35:01 GMT

Sorry pal but the workarounds involve not using a non host void family. Can you give me an example of a specific condition that you must use a non host family to cut another family?