Tedious truss detailing

[Gene Davis]

I am in V 10.08.a, and finding the structural part, as regards trusses, a little tedious. I wonder if I am missing something.

The little house I chose for my training exercise has a porch under roof, with a barrel vault ceiling. Inside the house the same roof has a scissors arrangement for the bottom chords for a while, then a half-scissors where rooms have flat ceilings adjacent a great room with a vault.

I am finding that Chief will shape a truss with appropriate bottom chord placement if ceilings are chorded, i.e., straight lines, but not if they are curved.

So, using CAD while in a backclipped vector view of the truss that is over the barrel, I edited the truss and am attempting to detail it. The attached pic shows results, not nearly accurate enough, nor nearly done.

Is there an easier way? A truss like this needs a detail for the truss engineer to get its chording right, with the shape of the barrel called out with dimensions at each node change, showing the rise and run.

How do you get things like this, plus all the other things needed as callouts for a special truss package, done in layout? Is there some detailing part of structural framing that I am missing?

[louis]

Gene,

Look in your cad details.

Another point: The truss companies around here do that for us. They want to do their own drawings.

[Gene Davis]

Louis, the truss guys here do their own drawings also. But for that barrel vault we did, they had to be led by the hand. We tried at first to spec for them that they chord it so as to make all the chords be tangent to an arch, and we gave them the arch specs.

What came back did not match our needs at all. We needed precision, because the arch was concentric to a package of custom windows below that tracked the curve.

Finally, we just gave them the dimensions of all the required break points. I am seeking to replicate this in Chief. See the attached, which displays what points are needed by the truss guy, and these are what I want to represent in my truss diagram in Chief.

Here is my problem, Louis. Let's see if you can help. Remember, I am in V 10.

I was able to edit the polyline that is the truss shape, in Chief, by taking a backclipped elevation view of the truss, breaking the line in a bunch of places along the bottom chord, then dragging up.

What you see in the pic attached to the first post here, is an approximation of the shape. I am unable to use CAD in the section view of the truss polyline and get the CAD to snap to the polyline. CAD is needed to establish the points for dragging up the chord, and the points need to snap to the CAD workpoints.

What do I have to do here, to get CAD to interact with that truss polyline the way I need?

[exallspaniab]

Here is a product which may be of some use for barrel vaults and domes - looks very promising.

http://www.usg.com/navigate.do?resou...Curve-Page.htm

[MikePreble1]

Is this close?
Mike

[billemery]

the geometric construction in the first picture show how the endpoints of the tangent lines can be precisely located. Notice the dialog box gives me the height and horizontal position with zero at the centerline of the building.

I can dimension to these cad points to precisely define the truss

I can now use the DBX information to position the roof planes.

The second picture show a very precise unedited truss.