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mmiles
2008-06-25, 08:22 PM
I am trying to make a family of muntins to nest into a window family, and maybe just to have available to place directly onto a window within the project environment. I have a few questions regarding the latter, but I am having problems with the family that I have to tackle first. Perhaps I am over thinking it, but I was canalbalizing different family matter, formulas and ideas from various others (my own, and found here in this forum).


Can anyone tell me what the error means in the attached image file? I am trying to create the formula for the "Muntin Number Horiz" parameter. It occurs after I try to "apply" the formula.
I do not want to have any muntin bars on the outside borders of my window sash (frame). I only want the bars to display inboard of the sides and top/bottom. Therefore I have attempted to create a parameter which controls an offset distance for a reference plane(s) which is in turn controlling the height (or width) of an array. But, even when I align and lock the array (using Last) the parameter formula generates constraints not met errors when I try flexing the model.
Can anyone offer a way to create the array without the bordering elements? I was told in old versions of Revit one could make certain members of a group invisible, but apparently not now. Any thoughts?
The attached revit file also generated the error found in the attached image, but somehow I was able to resolve it - Does it have something to do with mixing shared and family parameters?
If I wanted to simply insert a muntin family (with parametric array) onto a window in the project environment in lieu of nesting into a family would a face-based family be the way to go? my initial, spur of the moment, no-time-to-spare attempt with that didn't seem to work.thanks, I appreciate any and all comments.

Andre Carvalho
2008-06-25, 08:45 PM
Why don't you use voids to cut a solid and create create muntins instead of creating them as a family with array? See this thread:

http://forums.augi.com/showthread.php?t=82819

Andre Carvalho

mmiles
2008-06-25, 09:05 PM
I will look into the other method. for now, I have spent the entire day working onthe parameters and array stuff so it would be nice to have some answers to my problems- otherwise I may just decide never to array anything ever again because it is too difficult (which seems like a bad idea to me, so I don't really mean that).

Look at the second RVt file. I have worked out the problems related to the vertical flexing (i think). I used the formula to determine a count, then I deleted the formula and made an array using the count generated. then I re-entered the formula and hit apply and the error did not get generated. (seems strange I cannot apply a formula with a different count to an existing array, but....)

Now, I have a different but related problem, which I have run into before- and it is maddening. My width parameter should also control the array, but when a different width is applied the array gets all out of alignment. Try it and see what I am talking about. I assume there is something simple I am overlooking, but I cannot figure it out. Thanks.

chodosh
2008-06-25, 09:10 PM
Is is possible that your two parameters in said formula are not both set up as instance parameters? That's my first line of defense. ;)

HTH,
LC

mmiles
2008-06-25, 09:19 PM
LC,
I did satisfy the need for instance to match up with instance. The cannot find solution to formula for type "" seems to be related to the order in which things are applied (as far as I can tell). At this point, I am spinning in circles- some problems resolved only to appear later; forgetting how things were resolved, etc.

thanks.

I wish I could control my array width, but I can't figure out how to get the array to move with my ref planes when I apply various dimensions. The elements in the array get misaligned in a staggered way that makes no sense to me. ugh.....

Andre Carvalho
2008-06-26, 03:52 PM
I wish I could control my array width, but I can't figure out how to get the array to move with my ref planes when I apply various dimensions. The elements in the array get misaligned in a staggered way that makes no sense to me. ugh.....

I edited your muntin family and noticed that you created the muntin on one side of the center reference plane. So I corrected the left and right reference planes to be at equal distance from the center one. Then loaded it back into the main family and used array to last and checked "Constrain" so it will stay vertical and not drifting away when changing the width. I also locked the top array to the top reference plane to make it follow the height changes.

I hope it helps,

Andre Carvalho

mtyp
2008-06-29, 10:12 PM
I'm not sure if any else does this but its worth looking at.

I create two parameters for the array. One to do the calculation and the other to control the array. They look like this...

Array Calc = Width / Spacing (which returns a number value)
and
Array Parameter = If(Array Calc < 2, 2, Array Calc)

From here you can add a visibility parameter to the elements in the array so that they only show when the array parameter is greater than 2. And then I create a single duplicate that appears when the array parameter is less than 2. This means that i get the appearance of an array from a single object. With some consideration to the desired appearance and some clever conditional statements it can work quite well.

In doing this I noticed that Revit only counts visible objects, so in the case of these muntins you would get a correct calculation of objects whether there is a single muntin or an array.