Autodesk has confirmed the problem in 2016. The criteria are a bit weird but you should be able to re-create the problem like this:
- Create a section (possibly any view type) of a custom type with a shared and/or project parameter.
- Change type to another type after placement.
- Run Purge Unused and you’ll see your original type as an option (assuming you have no views already created with that type). Select that original type for purge
- Your section previously created will disappear.
So many problems with this. But I’ve found even more weirdness.
You’ll see that if I select a few sections 1) They kinda work in tandem for some reason and 2) I’m selecting a ton of groups somehow. Those are model groups by the way so I don’t know how section types and model groups are tied together.
I’ve already notified my teams to stay away from the tool. I’m a little hesitant to use it myself but there aren’t many options without macros, plug-ins or some Dynamo.
In the video below, you’ll see what I’m talking about. Autodesk can’t tell me why it does this but I am able to reproduce it over and over with a particular file. It is unclear why these particular views are marked for deletion but when Purge Unused is invoked they disappear along with “unused” view types I have in the project. What is really strange is the view types associated with these views are NOT deleted. Just the views. Which is bad enough.
I opened a ticket a few days ago about this, along with a before and after version of file, journal and a link to this screen capture. Initially the response was, I’m paraphrasing, “well don’t select those types for deletion”. Um… no. I actually tested that scenario of only selecting the section view types and purging them alone. Nope, still deletes the views. Ok, maybe it is because they aren’t on a sheet. Tried that, while looking at the sheet, nope, viewport removed from sheet when you click “OK” in the dialog. The tech I talked to suggested that a similar problem has been fixed in 2017, which is a fairly typical, and incredibly frustrating response from Autodesk. I made a point to explain a likely scenario:
- Project just finishes DD and is gearing up for CD
- Maintenance time and the coordinator decides to purge unused to help lighten up the model.
- In the process, with no indication, random views are deleted.
- Next time the sheets is issued, people swear views are deleted, tech insists someone must have done it. Doesn’t matter, time to do some rework.
I’ve had this scenario happen and I’ve ALWAYS written it off as someone deleting things they shouldn’t (like a section mark on a random plan, without thinking about deleting a view). And, I rarely let Purge Unused run with all items checked. Doesn’t matter, this seems to happen regardless of what exactly is checked. Especially given that the views are of types that aren’t identified in the purge dialog.
I’m waiting to hear back from Autodesk but I’m afraid that the answer will be “it is fixed in 2017”.