Nested Array - Parapet Cap & Brackets

[cgrover]

I started modeling Board and Batten siding as an inplace family and received a message about creating a family with a nested array. Since I'm not very accomplished with families I was wondering if someone could shed some light on "nested arrays" in families. Also how would one create a nested array. I'm also looking at a parapet detail where a small "brace" would be repeated every 2 feet or so; would this be a place for another nested array?

Thanks for the help.
grover

[beegee]

Firstly, have a look through the tutorials on nested families, then search topics here. There's quite a lot on the subject.

A nested array is basically where one family is nested in a parent family and then arrayed in the parent family. Like the palings in a fence panel for instance.

If you want, post your family for someone to look at.

It would take quite a while to explain this subject in detail.

[cgrover]

Thanks Beegee. I went through the toutorials and search the site. After reading the posts I'm still confused on the formula for a nested array.

I've attached the family I'm trying to make. The family is a parapet cap and I want to array the brace so they are at 2' O.C. Any advice or help would be greatly appreciated.

grover

[beegee]

I had a quick look at your family, it was based a generic wall based template I think. There can be issues with that template when attempting to constrain an element to the wall ends, which I think you need to do for a parapet cap ? ( ie: I often get the "over constrained" message in this template for some reason. )

Here's the approach I would take :-

1. Set up Reference Planes to locate the first bracket from the wall end/ parapet end.
2. Do the same thing at the other end.
3. Name these "Bracket Inset" and set as parameters.
4. Dimension between these two reference planes and set as a parameter _ "Array length"
5. Make sure the first bracket is aligned and locked to reference planes for its top and wall offset.
6. Array the first bracket - to last, leave the array number as 2 for now, and locate the last array member on the end inset reference plane.
7. Check that the last array is properly constrained.
8. Set a parameter called " Array Number " and make its formula =(Array Length/2'0")+1
9. Select the array you previously placed, select the array line, then the array number (2) and assign that to the parameter "Array Number "

That will array the brackets at max 2'0" centres and the array number charges as the array spacing increases.

As I said, I'm suspicious that this will not work properly with this template, but I haven't the time to check.

[cgrover]

Beegee,

Thanks for taking a look at this. I will give it a try and post if it works or not.

Do you think I should be using a different template than the generic wall based?

I also ordered Cyril's second book and I think that deals more with families...I can't wait to get it and try to get a better handle on these.

Again thanks for the help.

grover

[cgrover]

Beegee,

Here is the parapet cap I've been working on. It still isn't working right and I think I may have to try a different template. I have to use the "component" tool to attach it to the building. I would like to use the "wall sweep" command, so I will keep trying.

Another thing I couldn't assign the formula for the array number, it kept giving me an "inconsistent Units" error. So needless to say I've still have some work to do.

If you have any other suggestions I would appreciate hearing them.

Thanks,
grover

[beegee]

Hi Grover,

I'm now thinking that a family is not the way to go at all.

I think you just need a parapet profile that can be used for a wall sweep and the just add and array the brackets as either an in place or a generic family.

Nice and simple and gets the job done ?

[christo4robin]

I just posted a parametrically arrayed bar grating family to www.rugi.org under the Metals division. You can download that and reverse engineer it to see the formulas that allow different numbers and spacings of your roof brace.

I may be mistaken, but I don't think you'll have much luck with the sweep command to create your arrayed braces. You'll likely have to stick with the Component insertion method.