Help with Simple Mesh

[Jere]

I know very little about meshes. For the life of me, I can't figure out how to make this simple mesh. I've searched on this forum and read the ArchiCAD help, but haven't come up with anything.

I want a solid mesh as pictured. The base thickness should be 5". The outside perimeter and the line down the middle should be 2 1/2" higher than the reference plane. I just want to add two points in the middle of each rectangle which would be at 0" (or, at the reference plane).

Help please.

[Anonymous]

When you say "The base thickness should be 5" " do you mean
the height of the skirt ?
If so, select the mesh tool, set the skirt to positive 5" (which is
really negative relative to the basis plane) and draw the rectangle
you show in your image. Select the new mesh, enable the mesh tool,
and click on one of the corners. A pet pallet comes up where you
select the elevation icon and a dialog appears with a field called "height"
highlighted enter the 2 1/2" elevation above the basis plane you want
then hit the apply to all button and click OK.
If you go to the 3D window you will see a mesh 7 1/2" thick with
2 1/2" of it above elevation 0.0.
In plan, draw a line down the middle of the mesh as shown in your image.
Select the mesh, enable the mesh tool, and space click on the line.
A dialog comes up titled new mesh points and a switch that gives you
three options, select "fit to user ridges" and click OK.
Now you have a mesh with a ridge down the center the same hight
as the perimeter.
In plan, draw pairs of lines forming two crosses as in your image.
Place a hotspot at the intersection of the two pairs of lines and
delete the lines. Select the mesh, enable the mesh tool, and
double click on a hotspot, a dialog titled "new mesh points" appears
with a switch with three options, pick " no surface fitting" which
will place the node at zero elevation. Do the same for the other
hotspot and you are done.
Peter Devlin

[Dwight]

1:Mesh tool. 5" base. Rectangular constraint. Draw a square mesh.
1A: Elevate the perimeter nodes by 2.5"
2:Line tool - subdivide the square mesh.
3: Mesh tool. Mesh selected. Magic wand the line.
4: It asks: Add new points>> OK.
Now you have a ridge.
5: Mesh tool: Place a new node in each half.
6: Drag the new node to the center of each half using the rubberband division tool
5: Select each new node and lower by 2.5"

You would think that the new node could be placed in one step by using the rubberband tool with the mesh selected, but it won't always take - very frustrating.

[Dwight]

so between us you have enough to figure it out now.

[Stress Co_]

Peter wrote:
Place a hotspot at the intersection of the two pairs of lines and delete the lines. Select the mesh, enable the mesh tool, and
double click on a hotspot, a dialog titled "new mesh points" appears
with a switch with three options, pick " no surface fitting" which
will place the node at zero elevation.

The mesh tool should be set to the "polygon" drawing method. If the "rectangle" is selected ... you can't add a point in the field of the mesh.

[Link]

Here's my take on it:

1. Create a 7.5" thick mesh using the rectangular geometry method;
2. Draw a line down the middle of it;
3. In the Mesh Tool, with the mesh selected magic wand the line and add new points;
4. Keeping the Mesh selected, use the G key to change the geometry method to Polygonal;
5. Use your special snap points and ` key to force guide lines into the center of each half of the mesh and then double click to add new mesh points;
6. Use your 'Elevate Mesh Height' pet palette option to elevate the two new mesh points by -2.5".

Same thing really..

Cheers,
Link.

[Jere]

Thanks everyone for your help! The biggest problem I was having was adding a node to the centres of the rectangles. Switching to polygonal mode was the trick. Great to see how different people take different approaches.