Truss bolt direction - just for convenience or is there a higher structural purpose?

[gafftapegreenia]

This question has been on my mind a lot lately and I haven't been able to get a real answer.

This is the scenario I experienced. A stick of truss was bolted to a truss plate. Bolts go up through the bottom of the truss plate and nuts go on the top. Following this lead all the truss bolts then went through the bottom of the connections and had the nuts place on the top. However when I got to the top to put on a corner block on I was told that "the bolts have to go down for strength". Is it really for strength? How much does direction of the bolts matter in these situations? And isn't better to place the heads of the truss bolts inside the corner block because its so hard to properly tighten nuts placed on the inside of a corner block?

[derekleffew]

... However when I got to the top to put on a corner block ... And isn't better to place the heads of the truss bolts inside the corner block because its so hard to properly tighten nuts placed on the inside of a corner block? ...

How many times must I say it: "KEEP YOUR NUTZ OUT OF THE CORNER BLOCK"? (As you said, not for strength, but for the fact that it's difficult to get the socket inside the block to get purchase on the nut.)

Structurally it makes no difference which direction the bolts go. It amazes me that in my primary venue (where we try to make all the bolts go the same way just for the sake of consistency) and pretty much every where else too, every time a road person will tell us it doesn't matter. We know it doesn't matter, still it takes less than 10 seconds (so 12.5¢, at Rochem's $0.75/minute, (time that will more than pay off during the load-out)) to ask the crew or person at the first joint which way they are putting the bolts, and then follow suit. EXCEPT at the corner blocks.

Now on a vertical truss, 'nuts on top' just seems upside down to me. But whatever.

EDIT: Asked and answered. See

While on the subject, some have told me it's important that all the bolts face the same direction. True or false?

And subsequent posts.

[derekleffew]

From PLSN | Working the Gig :

How quickly time can be eaten. Load-in was supposed to be quick, with the fixtures hung and the truss ran out in four hours. Four hours turned into six and some change. The problem — truss connections. After getting 75 percent of the truss bolted together, someone noticed one out of five bolts were facing the wrong direction. Sounds stupid, but safety has to be the top priority. With thousands of pounds of equipment overhead, failure is not an option. Additional time was allocated, checking every bolt and fixing any mistakes. Poof, programming time begins to disappear.

So apparently, in DC, when you've got FIVE bolts per truss connection, ALL must face the same direction, lest the entire thing collapse. Safety First!
-----

Once the truss was floating, fixtures went on quickly. Thanks to some awesome prep work in the shop, focus tape made the hang quick. Along with the fixture placement, the focus tape showed where breakouts and specific circuits landed. There was no need to measure out the truss or to refer back to the plot. I will never knock focus tape again!

With due deference to FOCUS TAPE - YouTube , someone needs to elucidate the author that the proper term is http://www.controlbooth.com/wiki/Hang+Tape, not http://www.controlbooth.com/wiki/focus+tapes.

[jglodeklights]

*FACE PALM*

[mstaylor]

*FACE PALM*

Structurally it should make absolutely no difference. The guy tightening them will certainly appreciate it but there is no flippin' reason to stop and turn bolts. I didn't read the article but I find it hard to believe that was a 22 crew that did that. I have worked with too many of them and most are excellent hands. It sounds like a nonunion crew. Not to make this a union/nonunion debate, but in DC there are some pretty bad nonunion crews working corporate work.

[spribil]

In my humble opinion....on vertical pieces the bolt should come in from the top with the nut on bottom. IF the nut does fall off for some reason the piece is still "pinned." As far as structurally it makes no difference.

[len]

Apparently, truss bolt direction is a safety matter. PLSN | Working the Gig Mentioned that truss bolts not facing the same direction caused a delay in getting a show put together.

[josh88]

Apparently, truss bolt direction is a safety matter. PLSN | Working the Gig Mentioned that truss bolts not facing the same direction caused a delay in getting a show put together.

From PLSN | Working the Gig :

So apparently, in DC, when you've got FIVE bolts per truss connection, ALL must face the same direction, lest the entire thing collapse. Safety First!

That was Derek's response to that article, see above

[len]

Oops. I didn't realize that article had already been quoted.