Options for Specifying Pipe Length

I was working with some folks today who were used to the Land Desktop+Civil Design pipe layout interface that gave you the option for directly typing in a pipe length as you drew pipes in plan.  They like to try to keep their center to center lengths even 8′ intervals.

Click more to find out what worked…

At first, we couldn’t find a similar tool in Civil 3D…

We did find something that worked the way we wanted it to and actually makes laying out the pipes a little more visual than the Land Desktop + Civil Design method.

Toggle on your dynamic input (DYN), then using the distance field to specify your desired center to center length.

Also note that without DYN on, you can use the same tool by entering a distance value in the Command Line at the prompt “Specify Next Structure Insertion Point or [Curve]:”, after your first entry, the command line will now ask you “Specify Next Structure Insertion Point or [Start Point/Length/Curve]:” and you can continue adding pipes down the line.

The transparent commands also work from this interface.

EXCEPTION: For some reason, if you come back in to edit your network and begin adding pipes to structures, the first new pipe you create will not follow the length you specify, but each subsequent pipe will.  I am trying to figure out why.  If you know- please comment 🙂

If you already have your pipes in… Perhaps you roughed in some structure locations and now you want to clean up your lengths…  You probably noticed that you can’t change lengths in pipe properties or prospector.  But you can use the little triangle shaped pipe grip.  If your DYN is on, you can use your tab key to toggle either delta length or total length.  You’ll still have to move your structure, but this works pretty well in general.

(Click on this image to see it more clearly.)



  1. ChristopherF says:

    The program calculates the distance from where you click, not from the center of the structure or from the Center of pipe. So if you remember where you clicked from and measure to the end of the pipe you will get the correct distance. So if you want to use the method you need to make sure you click at the center of the structure or the center of the pipe. So not really a bug since this is how it is in all other commands, but not the expected result.

    I tried it with the nearest OSNAP and didn’t get the correct value when going from the center of the pipe. I suspect that is pulling the actual elevation of the pipe centerline rather than the 2d length. I tried to set the elevation picker to 0 in both 2007 and 2008, but in 2007 its not showing correctly and in 2008 its not turned on and I don’t know how to turn it on.

  2. i would expect the structure glif (aka golden snitch) to snap to the center of the manhole. When I draw pipe networks and I know I am connecting structure to structure, I turn my osnaps off and rely on the structure glifs. Where the heck else would it snap to? I’m confused. I guess I need to rethink that and perhaps use the center osnap. I just have to be aware if my “z grapper” is on or off.

    In 2008, the Z grabber is under options… I forget which tab right now.

  3. The DYN tool has its origins in plain old Autocad, but it allows for some pretty cool stuff in C3D. In addition to the items Dana mentions, with DYN on, you can also graphically resize pipe diameters using the triangle grip at the midpoint of the pipe. When editing profiles, you can specify the station and elevation of a PVI location when grip editing. There are lots of others and perhaps this warrants a future blog posting….

  4. rgraham says:

    I have heard of ‘horror stories’ with users having the DYN activated in Civil3D. Unexplained crashes, unexplained results, etc. Anyone see anything along these lines? If this is true, then do we just turn on the DYN when we want to do stuff like that and then turn it off again? – Great site with lots of good treasures. You guys (and gals) should write a book called ‘Civil3D – tips, tricks and blogs’ 🙂

  5. DYN isnt useful all the time, esp for the command line intensive stuff. i have users that have it on full time in civil 3d without much issue, but i have not sat next to them all day forever to know if it causes them unexplained crashes. it can slow down your performance a little bit and confuse you if you are a commandliner. i treat it kinda like my running osnaps. on when it is handy, off when it ain’t.