Truss style Gantry

[D.C.]

Toronto the week before, there has been a few others.

If you look at pictures of the Toronto collapse it is very clearly a scaffold structure that has collapsed and no report has been released so far, let alone one claiming truss beam failure. Just because stages collapse and truss systems are often to hang lights above a stage doesn't mean that all truss designs are fundamentaly flawed.

Anyway, given that the thread is about a cnc gantry built from multiple 4mm thick pieces of steel box section I doubt very much that any force is going to be generated that will come close to causing structural failure, death and destruction just so long as an invading column of tanks don't decide to take a short cut through my garage. :)

I was more interested in a comparison with the usual designs of gantry, like for example a couple pieces of alu extrusion bolted together or the unsupported L shape, bolted to plate supports at either end.

[Musht]

If you look at pictures of the Toronto collapse it is very clearly a scaffold structure that has collapsed and no report has been released so far, let alone one claiming truss beam failure. Just because stages collapse and truss systems are often to hang lights above a stage doesn't mean that all truss designs are fundamentaly flawed.

Sorry , where did you draw that i said all truss designs are fundamentally flawed?

As said not a rigger, not playing one on T.V. not playing one on the internet, haven`t said anything about the inherent safety or otherwise of trussing, of which many miles are hung above peoples heads very safely every day and night of the week.

Eaxmple of stage collapses, of which there has been multiple incidents in last 5 years, was used as an example of how aluminium truss or indeed steel tubular scaffolding will NOT:

"deal well with forces in all sorts of directions"

It is immensley strong for it`s weight but will fold up like a wet newspaper if forces are applied in the wrong direction.

Sorry you couldn`t read to end of the post before having to reply

" cnc gantry built from multiple 4mm thick pieces of steel box section"

a link was provided to a 3d model of a staging system that uses steel box section with triangulated reinforcement, more similar to your requirement than 3D alloy truss.

"comparison with the usual designs of gantry"

Cause you missed it last time:

"weight is less of a concern apart from moving the mass of the gantry and possibly damping resonance?"

Not questions can answer afraid.