Content Builder - Dimensions (Len Values)

[MD81GM]

Hi,

I am trying to modify the DW144 Round Duct Square Branch Takeoff in the content builder. There is one dimension in the content builder (LenA1) which is the length of the takeoff. I am trying to add a line parrallel to the duct through the centre of the takeoff to indicate a damper (instead of adding a damper on the duct branch).

I have added geometry (line), and points:

• point 1 is on the midpoint of the line
• point 2 is on the start of the line
• point 3 is on the end of the line.

I wish to constrain the midpoint (point 1) to the centre of the takeoff, and give the line (point 1 to point 2) an "Len" value equal to the diameter of the take off "D1" + 80mm, so the line will extend 40mm outside the takeoff on both sides.

How do I constrain the line to always fix the midpoint of the line to the to the centre of the the takeoff and add an "LenA2" value to associate the length of the line with my "model/size parameter" which I have set up. LenA2 = D1 + 80.

Whan I add a dimsnsion it asks for a value, I cannot find a way to associate the dimension to my model parameter LenA2.

Pdf attached.

Thanks for the help, I am somewhat familiar with parametric parts and in autocad have no problems with "Len" values.

Much appreciated.

[dbutts7]

OK, this is a good one - can you copy it to a custom catalog, and post it here? I'll take a shot at it...

thanks - db

[MD81GM]

Thanks David, much appreciated.

Had given up on this, was consuming way too much of my time, need a refresher course really, 2011 was the last time I used MEP. So much to do to get the template set up.

I have attached the dwg and xml file, is this enough for you?

Cheers,

Martin

[dbutts7]

OK, without going into a long sermon, here's the key things you need to do.

Remove LENA1 as the main dimensional parameter

Add two dimensional model parameters that are for each side of the damper line (or solid, whatever you''re modeling as the damper) - name them LenA1 and LenA2

place the dimensions so that LenA1 goes fomr the start of the takeoff to the damper, and then place LenA2 from the damper to the end - so you now have two dimensions instead of one

On the part palette, under Model Parameters, select LenA1, right click and choose Edit

When the Model Parameters dialog opens, Select LenA1 - for the Equation, type in LenA2 - this will set both parameters equal to each other.

This should give you the equidistant split....but this may not be what you really need. Fittings like this use three work planes - XY, YZ and XZ, which represent the three faces. A couple of releases ago, they added the ability to add more work planes to the fitting.

If you select Modeling > Work Planes, then right click, pick Add Work Plane.

You can choose between offset, top, front, left, bottom, back, right, custom and reference. I would add this work plane first, then associate your line that indicates the damper with the new workplane. Like Revit, AutoCAD MEP parts work better when associated with a 3D plane, and associate the dimensions with that plane. I would add a top plane so that you see the line in that point of view, using coincident points to lock the start and edit points.

You can also add offset planes associated with these points to indicate the ends of the damper, and add dimensional parameters to control them as well - and then add an offset parameter that would read like this: Offset1 for the length from the edge of duct to damper endpoint, and then an equation that reads Offset1 = D1 (hopefully this is clear)

I did a class a while back that displays how to do this in regards to adding symbols for elevation views of valves, so you can have two or more 2D symbols indicated with a MVPART (Which Revit CAN'T do). I'll attach the document so you can refer to it, but youre beter off adding these planes first.

Maybe I need to cover this in my content class for AutoCAD MEP at AU this year...this is a good one. Let me know if you get stuck, or if this is still a little vague.

thanks - db