Forums >> Revit Building >> Technical Support >> how to make Parametric array in families. revit2011

Jonashc

active

Joined: Fri, Sep 24, 2010
9 Posts
No Rating

Hello I am trying to make a parametric drain for the bathe room. The drain cover has holes( Voids) for water acess. these are copyed. when i change the lenght of the drain i need a parameter that makes voids to apper in the correct array dimesion. and also keep the sam distance to the ends???

 So if you are a math nerd help me plesae..

Attached Images

This user is offline

jlights

active

Joined: Tue, Dec 18, 2007
146 Posts

Modeling voids in a drain is overkill, and using arrayed voids is overkill as well. This level of detail is not necessary to get your design intent across. I would suggest using model lines, which will appear in plan as well as 3D views, and set them to Fine visibility only.

Start with a Generic model family (unhosted) and draw the drainhole shape you want. Load it into the drain family. Then you can array ths one object.

Your drain family's origin point should be at one end, not in the middle, so that as the drain grows in length, the array can flex with it. (Note: With the origin in the middle the array would have to grow in both directions- I don't even think you can do this with an array.)

Assuming the distance from the end to the first hole is X and the distance from hole to hole is 2X, place the first instance of the hole family and create a locked dimension from the end to the hole. then you can create an array of holes, select the array, and add a parameter to it to tell it how long to be. (Without doing a mockup myself I can't tell you step by step how to do this, but experiment and read the Revit help for more ideas.). You may or may not end up with the space at the end the same as the space at the beginning. I'm sure it's possible to do, but I'm also sure that if it's off by a bit it's not going to affect your project, and you need to decide whether you have the time to make this array of holes perfect is that important. Unless you are doing a closeup rendering of the sink drain it will not even be noticeable.

Another option: if you have several specific lengths of drain, create a type for each length. Then you could create an array of holes for the longest length; ungroup the array so you have a series of separate objects; and apply visibility parameters to groups of holes that appear in the longer types. Remember that ALL the holes will be visible in the family, as visiblilty parameters only affect visibility in the project environment.

HTH.

-----------------------------------

jlights

This user is offline

View Website

TKennedy

active

Joined: Wed, Oct 7, 2009
654 Posts

The insertion point doesn't need to be at one end, though I prefer it to be whenever possible. It may or may not make sense in this case.

Voids are indeed overkill, and your family performance will suffer. Model lines are the way to go. Either way you go, arraying will be the same.

Make a Ref Plane at both end of your family. They should be placed at the start and end of your array, and locked to the ends of the family (this is to give you something to lock the array). Create the objects you want arrayed, and add a Ref Line running through the center of the objects to be arrayed, parallel to the Ref Planes you created. Array the objects and the Ref line, make sure you select 'Move to:  Last' on the options bar. With the array still selected, you should see a bar running from one end of the array to the other. Select it, you will have the option to assign a parameter to the array. Assign a parameter. Use the align tool to lock the arrayed Ref Lines to the Ref Planes. Now your two end array groups will stay locked at the ends, and the array will fill in between them according to the value you set in the array parameter. You can create a formula for that parameter that automatically increments with the length parameter, but it's likely going to work just as well to set it manually for each type.

Sorry if this isn't very clear, I'm running off caffeine and the memory of sleep at the moment. Let me know if you need any clarification.

This user is offline

itsmyalterego

active

Joined: Thu, May 28, 2009
829 Posts

Parametric void arrays work by far the best if you use a nested void family.  I remember I got that advice after I couldn't get it to work any other way.  Nesting families isn't as complicated as it sounds. 

Important thing to note is to save the width/spacing as an integer (rounding) so you can use it for the array number label. 

In the attached pic, the nested extrusions stretch to match any height, and array across any length of walls.

Edit:  For your formula... try.. (width/1")-4".  This will fill the space to the nearest inch, leaving 2-2.5" at either end. 

if you wanted the holes to remain absolutely centered even with an arbitrary length, try a new parameter for the dimension from the edge of the grate to the first void:   .5(width-(width-4")) as a non-integer number. 

The purpose behind this formula being to split the remaining uncut top plate equally... It's easier to divine that number than anything else.   You have to lock your array to a left/right plane.  "Centerline" is not a suitable plane for an array to dimension from, which was my first instinct for making symmetrical voids--IE, two arrays going left, and right. 

That formula will probably explode in your face, I never have luck with parameters on the first try.  But give it a shot.  Good luck.

Attached Images

This user is offline

cketros

active

Joined: Mon, Oct 27, 2008
36 Posts
No Rating

I did some thing similar, may be you could modify as you like.

This user is offline

cketros

active

Joined: Mon, Oct 27, 2008
36 Posts
No Rating

sorry, this one little better

This user is offline

mbsteve

active

Joined: Fri, Sep 22, 2006
759 Posts

Why not make the drain like the real thing, usually they are in 2 foot increments, trough and grate.

This user is offline

Mr Spot

site moderator|||

Joined: Mon, Jan 12, 2004
2889 Posts

Here is a parametric example of what you are trying to achieve.  I would probably hide all this geometry at everything but fine detail level to avoid performance impacts and a big block blob in plan...

-----------------------------------

Regards,

Chris.

Co-Founder | BIM Consultant | Software Designer  B. Arch)

Xrev Revit API Addins | Revit Rants

This user is offline

View Website

Parametric Arrays

1

Parametric Arrays?

1

Creating parametric (array) cabinets

3

Editable nested family inside parametric array host family

1

Centering a parametric array in a family - RAC 2009

0