Revit 2018 has killed nested families

[asmenut]

We have multiple nested families that we created in revit 2017 (i.e. conveyors and other specialty equipment).  When these were created we added strong reference planes within the individual families in order to align properly (and in some cases, we would align to a face, edge, etc. (have no choice since revit gives SO FEW CONSTRAINT METHODS SUCH AS CENTER, PARALLEL, ETC.), and all worked great.  Now comes 2018 and when copying some of these families to create new Nested types, we are no longer able to constrain properly, even trying to use family based reference planes.  Not only do I get a message saying the aligning to an edge or face is not allowed, only reference planes, lines and levels, these nested families (new and old if we modify an existing family and save with new parameters) BREAK.

What is up with this.

Also, since i'm here, we utilize a lot of vendor supplied equipment models that we create families from and their locations (elevations) will vary depending upon their design requirements.  In 2017, I was able to create reference planes and set dimensional parameters in order to align them as required. And all worked great. But now in 2018, I am have to create a new parameter specifically for the "Base Offset" in order to get new equipment to adjust it's elevation (and I am using a generic specialty equipment template).

Please help.  This is becoming a nightmare, and is starting to upset the heads of state because I am having to spend so much time repairing (and in some cases, re-make these families), that it is starting to affect timelines (Including Bid and Construction).

[Sahay_R]

Can you share an example or two?

[asmenut]

Attached are a couple of smaller families. the rehang module is a stripped down version of a section of equipment we use, so I created a family that can be copied in a project to achieve the length required.  In this family (derived from a STP then DWG) it shows the addition of the "Base Offset" parameter so the family will locate properly (the visual dim/parameters are for user understanding only).

The second is a conveyor drive/idle end. We use this in conjunction with various conveyor layouts (i.e. incline, radial, radial offset, etc.), and is placed at both ends of our nested conveyor assembly families. This nested family uses both imported STP/DWG family components (motors and flange bearings) and a standard revit extrusion/sweep family. 

Thank you for your response.

[ToanDN]

Edit:  I expanded your formula and realized I missed a number in there.  The calc is actually correct so forget about what I wrote below.  Then, what exactly are the issues with these family?  They behave properly when I tested.

____________

So if your problem is only the BASE OFFSET not giving a proper result from the formula then I would suggest using a report parameter instead.  It will make the family lighter since less calculations are involved.  I can take a look at why the formula gives the wrong answer later.

[asmenut]

The problem with the vendor equipment (i.e. stp/dwg import), is that without the parameter "Base Offset" and its subsequent linking to the property "BASE OFFSET", the component will not adjust as needed.  As far as the nested families, Revit is not acknowledging the inherent planes that are being inserted into the nested families.

[ToanDN]

Wait a minute.  You don't see it from your end?

[asmenut]

Toan, 

First, Thank you very much for yours and everyone else's help.

Second, If you remove the parameter link to the Base Offset, and attempt to locate the family part via parameters, you will see that the part will not move.  I may be approaching it incorrectly, but in 2017, I have been able to set the elevation without having to link a parameter to the base offset.  It isn't a major issue since I was able to determine that the failure is linked to the Base Offset, but it's one of those things where "If it's not broken, don't try to fix it".  

[Sahay_R]

OK - I unlinked the Base Offset parameter, loaded the family, and was able to move the family by typing in Offset values. 

1.

2.

Wasn't this the desired behavior? Are you missing a step? Am I missing a step? IS this just a case of the Monday Mornings? I am totally bamboozled....

[asmenut]

Rsahay,

Manually changing the offset is not the problem.  My mistake for not explaining properly.  This family is located based upon "Bottom of Track".  The bottom of track is located 120mm below "Top of Track".  And the top of track is actually 4 179/256" above where Revit placed the imported cad model (i.e. base offset = 0'-0".

We utilize multiple pieces of equipment in our designs (yes factory design would be more efficient, but heads of state want to use Revit for all Disciplines (including process design) for the BIM (we are trying to get there 🙂 ).

The Speed in which we need to get these into revit (upon receipt from supplier) does not bode very well for taking the time to locate where is where and to relocate to 0,0,0 (Autocad), so it is essential that we locate inside Revit.

In revit 2017, it was not necessary to locate based upon "Base Offset", so our Parameters worked great.  But ever since 2018 (we are currently using 2018.1), it has become a serious issue (even more so with our nested families).  After diagnosing the problem, it was found that the inability of our parameter data to locate a part properly, was caused by the "Base Offset.  I then started having my people measure the default base offset from where we were needing to locate from and add the "Base Offset" parameter to compensate.

[ToanDN]

Do you have an equivalent 2017 family?

[asmenut]

Here you go.

[ToanDN · Accepted solution]

I guess I am really thick because I still don't get what the issue is.

I loaded the 2017 family in a Revit 2017 project and a 2018 project and they behaved exactly the same. Upon opening the 2017 family in Revit 2018, again, it works exactly the same as if I open it in 2017 (yes I opened them side by side to compare).  You choose to constrain the CAD family to the BOTTOM TRACK reference planes so moving the planes will move the CAD family, and subsequently, updates the Base Offset.

The Base Offset parameter is automatically generated based on the distance from the lowest point of the nested family or the import family to the reference level in the host family.  It CAN be used to locate the nested/import family elevation but you choose to use a reference plane to control so the Base Offset is more like a reporting parameter.

Am I still missing the point?

[asmenut]

Thanks for the help.  I rebuilt the family and it seems to be working fine now.  Not sure what was happening but as I put together more families, I will investigate this further.  Sorry for the bother.