Trusses

[stephanschneller]

Hi,

Im about to create a truss with 2no top chords and 1no bottom chord and
wondered what would be the best way to do so?

I've attached a sketch showing what I intend to draw.

My first idea was to set up the frame in AutoCAD Structural Detailing and
then link it through to Revit (model or family)....not sure whether this
would give me the flexibility I need in terms of length, width etc.

Does anyone else has a good idea?

Regards,

Stephan

[dhurtubise]

Why not simply build a truss in a Revit family?

[kmarquis]

You should absolutely build your own. I've made hundreds and hundreds of trusses just like this. I've attached an example and you could probably just edit the one I provided.

Good Luck.

[stephanschneller]

Hi Karenm,

Thanks for your reply.

My problem is Im not quite sure about the sizes of each member (top chord, bottom, diagonals etc) so Id like to be able to change them in the project which wouldn't work if they are 'just' extrusion in the truss family.

Any idea how to make this work?

Regards,

Stephan

[dhurtubise]

Just make those parametric. Attach some dimensions parameters to it and youre good to go.

[kmarquis]

Maybe you could make all the truss elements as separate families, make them Shared and then nest them into a truss family similar to the one I've posted and set up parameters. That way you could change the size of the chords and supports in the family. I'm not sure if this would work well or not. You would just have to factor in the time it would take you to set this family up to work perfectly in the project or just plan on going in and editing the family in the family editor.

[dhurtubise]

There's no need to share nested family because you re not looking to schedule every component of the truss are you?
But you could use nested families for sure. Ill try to put a quick example together

[dhurtubise]

Ok, here's a quick and dirty example that should get you on your way.

[kmarquis]

Oh I guess you're right. I was thinking that he would need to change the actual size of the chords and vertical supports in the project but I guess he could do that with extrusions. I get the whole 'Shared' thing confused sometimes.

[jsteinhauer]

Ok, here's a quick and dirty example that should get you on your way.

Daniel,

That must have been a very quick example. I'm surprised that you used an extrusion over a sweep. Is there a reason for this when building trusses? I don't build trusses, so asking this question is for my benefit and not to be a donkey.

Stephen,

I prefer to use sweep for my family content. I find they're easier to manage/control. The other thing about sweeps is you can use profiles to control your cords. These can be labeled and swapped out and rotated as required. I don't have an example available for you, but I suggest looking into using sweeps instead of extrusions.

Best of luck,
Jeff S.

[dhurtubise]

Not sure why you would use a sweep in that example since the truss is...straight. So theres no need to follow a path. Of course it would do the same thing but then a sweep would force me to create a path & a profile, an extra step i dont have to do with extrustion.
So unless i really need to use a nested family... extrusion is the simplest way ;)

[stephanschneller]

Hi,

it's been a while...but Im now back on my truss family.

I've set up 2no top chords and 1no. bottom chord using a sweep/ extrusion as suggested.

so far so good but Im now struggling to create the diagonal which means I need to create a path in space between the top chords and bottom chord.

I simply cant work out how to pick the points in space to create a model line (or reference line) which will be the path for the sweep.

I have attached my truss family and would appreciate any help.

many thanks,

Stephan

[stephanschneller]

any ideas? Im a bit desperate to find a solution...

[kmarquis]

I would download the truss family that I have uploaded and take a look at that. If the diagonal is the same thickness from the front of the truss then just do an extrusion. You might want to do an extrusion in a seperate family and nest it in.

[stephanschneller]

Hi Kmarquis,

Thank you for you reply.

I had a look at your family but the difference is that you diagonals are in the same plane as your top and bottom chord.

As my truss has two top chords and one bottom chord the diagonals will be in a different plane.

Basically I have difficulties to the define the path for my extrusion...does this makes sence?

Regards,

Stephan

[kmarquis]

Oh...I see your problem..your truss is round and it's angled. Can you just model the truss with square shapes instead? Lol...sorry.