Parametric Revit Family - Parameters sometimes work, and sometimes don't

[Anonymous]

I think I'm going insane.  For some reason, the attached family will not behave consistently.  Here is the problem.  I want the width to be changeable.   And generally it works well.  If I go from 16' to 15' it's fine. If I make a large change though, it breaks.  So from say 16' to 3'.  YET.....  If I slowly change the width from 16' to 15', then 15' to 14', then 14' to 13' so on until 4' to 3' it will work.  I don't understand this!  This means there is nothing wrong with the framwork and parameters nor the model elements, yet it breaks sometimes. 

Does anyone want to take a look at this and give any suggestions on what is happening.  It boggles my mind and I've spend hours trying to fix this behavior.  In the end I'm trying to use this same trim family as a nested family in an arched door opening and in a garage door family.  This means it's width range should be between 2' to 20' or there abouts.  And, like I mentioned, the family does work with those width values, as long as you coax it there in increments.  Which is something you can do in the family editor, but you cannot reliably do when loading a whole bunch of family types nor can you control what the end user will do.

[ToanDN]

@Anonymous

Try the attached file.  I changed the parameters to Instance for easier to flex them.  You can change them back to Type.

[barthbradley]

...lock the TIPS of the arch sketch line to the x and y Ref. Planes as well. 

[barthbradley]

Thanks, @Anonymous.  I sure glad I didn't have to do the "Bend and Snap". It wouldn't have been a pretty site. 

Now all we need to do is find you a credit-worthy solution.  What's going to do it for you?  

[ToanDN]

This one you can flex it in 3D using grips.  See screencast in a few minutes.

https://knowledge.autodesk.com/community/screencast/93392366-a153-4a21-bfda-10e03361118d

[Anonymous]

@ToanDN @barthbradley @Corsten.Au

You guys are all awesome and I love the help!  I think your solutions are great.  Having the radius control the arch seems to work smoother, so that, I think will be my solution for now.

The thing that still annoys me beyond comprehension still is that my original family works but doesn't at the same time.  WHY!!!  Why can the width be 2 or 18 or more, but it just can't be changed from 2 to 18?  Why do you have to incrementally change it from 2 to 25?  It defies logic. What's even more infuriating is that when you load it into a project, it behaves fine.  You can jump from 2 to 18 with no error.  But in the family editor this is not the case.  I wouldn't worry about this except for I am using this trim family nested into a couple door families.  When they are nested and I flex the door family they break.   Sooooo annoying.  In the end, I just really want to know what's going on here and why.

I also really liked my original family because it was able to make three types of arches: Segmented, Semicircular, and Horse Shoe.  Controlling the arch with the radius doesn't allow this. But... practically speaking, for my purposes I probably won't use the horse shoe, and the semicircular can be almost achieved by allowing an arch height value that is just barely smaller than 1/2 the width value.  I can control that with a formula and no one would be able to see the difference.

[barthbradley]

The secret is to incrementally widen it in the family and save, as the family default, the widest opening you'll ever use in a project.  This will considerably reduce the chances that it will break in the project.  Still, it's not a 100%. Sometimes things just inexplicably break in Revit.   You can break OOTB families if you try hard enough.  

p.s. Parameters that act as stopgaps are a good way to prevent users from accidentally entering a bad value (such as the "Spring Offset Ctrl" I showed you).  

[ToanDN]

@Anonymous

See the attached family.  It now works for any kinds of configuration: shallow arch, semi-circle, horse-shoe, camel toe, etc... etc.