[SML] pipe grid question

[Richard John Archer]

Last week I had some questions about our pipe grids here at Cornell.  You might remember we had half batten clamps and the CU engineers were not happy.   Well……..we bought some full batten clamps to replace the halfs but the holes didn’t line up.   We jury rigged something but when we finally took down the half clamp  …..it had no “makers” stamp or other info so we couldn’t tell who’s it was.   It was  close to if not 3/16 steel rathe than the 11 ga  (1/8”) Clancy makes theirs out of.,, as I mentioned, the holes don’t align with today’s Clancy clamp..the clamp steel above the pipe bend  is longer,  there are two holes in the clamp above the pipe  for bolts to tighten the clamp around the pipe and a third hole for attaching it to whatever might be used to hang the clamp (in our case it is a clevis fitting on  threaded rod)

Any body have any idea who might have made this beam clamp?   There are no markings on the cross grid connectors either.    Building was built 1986-88.    Clamp looks much more robust than present JR Clancy 1/2 clamp so we are wondering if it has a higher load rating.   We’d certainly like to avoid replacing all these clamps in this and our  five other spaces with fixed grids.  Present day Clancy clamps have load ratings stamped in.  H&H  clamps have manufacturer stamp (but no load rating) 


DickA
TD, Cornell U



> On Oct 9, 2017, at 11:56 AM, Richard John Archer via Stagecraft <stagecraft at theatrical.net> wrote:
> 
> 
> University engineers are looking at the pipe grids in our spaces (not yet in the proscenium)  .   Seems like an odd time after 30 years in the building ….but…
> 
> Grids are all  kind of typical looking …..two way #40  1 1/2” pipe grid ,  cross grid connectors (so one direction of pipe below the other direction) ,  a bit over 4’ x 4’ spacing….beam clamps with 1/2” threaded rod seemingly  spaced appropriately  The problem is with the  pipe clamps….most appear to be JP Clancy   half pipe clamps (or other manufacturer? Clancy did Proscenium rigging).  Half pipe clamps only have a 200 # RWL  .  Why would anyone install these in a grid?  ….they just adequately  hold up the pipe weight.    Am I missing something here?    Was this some Cornell value engineering at it’s finest?  I’m sure original theatre consultants wouldn’t have spec’ed this (ARTEC) 
> 
> Needless to say, we’ve been hanging  up to maybe 200 fixtures in there for years.  Biggest flexible space is about 50 x 50. 
> 
> 
> 
> DickA
> TD, Cornell U 
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