In the first post on Project setup, we covered a list of criteria we need to get started designing a plant in CADWorx. We created a general needs list which designers should be familiar with. Before we move into applying the information we gathered, we need to cover creating templates and project locations in AutoCAD/CADWorx.
For our particular pilot project, our civil documents indicate that our plant coordinates start at 334’ 9 3/4” West and 404’ 4 5/8” South. The benchmark elevation is at 302’ 6 1/4” above sea level. The plant is oriented at 8.9 degrees east of north.
From this information we have to make a decision based on 2 facets our project. The first item is the plant coordinates. Note is that AutoCAD has some floating point precision problems at large coordinates or with non-orthogonal revolutions:
These problems occur pre-CADWorx 2011 and typically in AutoCAD 2007 or above. Due to the new modeling engine in 2011, the errors mentioned about don’t exist. If you do find any errors, please use the Contact US page to let us know about them. If we will be referencing coordinates in our production packages (isometrics and/or orthographic drawings), we need to decide how to offset our model.
The second consideration item on our check list is to know whether the plant is oriented-to due north or not. If our plant has any orientation change from north, we will need to use a technique to get our real coordinates and allow our model to remain with north either in the +Y or +X directions (per industry standard).
To address our plant coordinate and orientation issue, we have 2 features we need to use:
1. Named UCS-An AutoCAD feature.
2. ISOGENSETTINGS- A CADWorx feature.
Depending on your project, you can implement whichever of these features that you need. By using a named UCS (say we name it ProjectUCS), we will be able to set that UCS current in AutoCAD and id points based on that UCS, no matter where our model is (we’ll create it close to 0,0,0 to avoid those pesky revolving issues). Also, if we use ordinate dimensions while the ProjectUCS is set in the viewport, we will get our x,y coordinates placed appropriately on the orthographic drawings. Unfortunately, the ANOTELEV command doesn’t recognize the viewport UCS so most likely we will have to have our model at the Z elevation we need for annotation.
The second feature, ISOGENSETTINGS, controls the output for the isometrics. By using ISOGENSETTINGS, the isometrics will display coordinates based on our offset and orientation set in the dialog. Since the settings from this dialog are stored in the drawing file, we will create a template model for the project.
To get started on a template, let’s create a new drawing using Imperial.dwt (I’m in the US after all ).
You should get prompted to select a template (choose Imperial.dwt). It’s in the <install dir>\Support if you need to look for it.
The easiest way to create a ucs is to base it on an existing object. To do this we will create 2 lines. To create our first line, start the LINE command and enter –334’-9-3/4”,-404’-4-5/8”,302’-6-1/4” and hit enter. Next instead of picking a point, we will set an angle override by typing <81.1 and hitting enter. Drag in the positive direction and pick to create our first line.
Next, copy and rotate the line –90 degrees. This two lines will create our x-y plane when we create our UCS.
Now we will create our named UCS. Start the UCS command.
You should be prompted to specify the origin of the UCS. Pick at the intersection of the two lines we just drew. For the specify point on X-Axis prompt pick the endpoint of the line running down to the right. To specify a point on the XY plane, pick the northernmost endpoint of the line running north.
Start the UCS command again, this time, enter NA for NAmed and choose save. Enter ProjectUCS for the name to save the current UCS to. Now in our ucs list you should see this:
Thankfully, setting up ISOGENSETTINGS is much easier. Enter the same values for the x,y, and z. For the north direction enter 81.1.
Erase our reference lines. Let’s purge our drawing to make sure no extra items clutter our project.
Save the drawing as a template (.dwt). Mine will be called Coordinates.dwt. You will probably get a warning about saving a template inside of CADWorx. Since we purged our file, you can ignore it.
Now when anyone creates a model for our project, they should use this template and their drawing will have the ISOGENSETTINGS correct, and a ProjectUCS they can use to id points in the model.[Download not found]