Unistrut Trolly

[rwdenney]

Engineering, brings to mind Millennium Tower in San Francisco.

Plus a lot more big screw-ups than that.

But it's often construction and maintenance that don't follow the plan or see things happening that lead to real disasters. The Hyatt Regency walkway collapse in Kansas City, for example, was a construction mistake. The design showed tension elements holding up the walkway in the middle of a large, fabricated square tube. The tension element was supposed to go through the square tube of the upper walkway to the lower walkway, with a nut in a threaded section in the middle of the rod for the upper walkway. Obviously, that's hard to fabricate, and I can imagine construction guys complaining about engineers that don't know how to make things, and with reason. But they constructed it so that the tension rod from the top terminated at the square tube, and a second element started adjacent to it to go down and support the lower suspended walkway. That would allow them to thread the ends of the rods only--much easier. But it meant that the threaded nut under the upper walkway, which was sized only to hold the upper walkway, now had to hold both walkways. The square tube was fabricated by welding two channels toe to toe, and the nut and washer fatigued the weld and broke through.

(from the decent Wikipedia article on the disaster.)

I was finishing up at Texas A&M in the summer of '81 when that occurred, and my steel professor was on the team that evaluated the failures.

Rick "can't even remember his name, now, but I can remember the story" Denney

 

[William Terry]

Not a biggie. just added a Unistrut trolley and a chain-fall over the lathe and mill...just for viewing pleasure...lol
My back is not what it use to be, taking care of what I got. Should be nice for chucks, vices and so forth.

View attachment 506115

LIKE THE TROLLY. I need some info, I have a Sheldon Lathe, Cat. No. EM-46-P and a Bridgeport mill with a set of collets. What would I need to use these collets in the lathe, if they can be used in it. All advice is appreciated. BTW i am a beginner at this. Thank You all.

 

[Larry$]

What would I need to use these collets in the lathe,

Bridgeport, likely R8 collets, meaning they use a draw bar. I've never seen an adapter for this use, doesn't mean you couldn't make one. But I'd buy and ER chuck & collets, or 5C if you have other uses for the collets (Spin Indexer?) R8 to ER adapters are widely available and not terribly expensive, so you could use the ER collets on the mill. ER basic chucks are relatively inexpensive or you can get one with "Run-Tru" adjustability.

 

[pontiac428]

Rick @rwdenney, thanks for the sistered beam idea, that makes great sense.

As far as the holes in the web, I was the electrician and the work was inspected. I did not drill one single hole, because the joists came from the factory with 2" knockout fenestrations for exactly such a purpose every foot along the span. It's all by the book, above board and up to snuff, pope's blessing, skookum, and (naturally,) kosher.

 

[verbotenwhisky]

Rick @rwdenney, thanks for the sistered beam idea, that makes great sense.

As far as the holes in the web, I was the electrician and the work was inspected. I did not drill one single hole, because the joists came from the factory with 2" knockout fenestrations for exactly such a purpose every foot along the span. It's all by the book, above board and up to snuff, pope's blessing, skookum, and (naturally,) kosher.

Pontiac428, below are my thoughts, and I would consult the manufacturer for their thoughts if cutting holes are required.

 

[verbotenwhisky]

Engineering, brings to mind Millennium Tower in San Francisco.

A leaning building..... Interesting, I was thinking more along the lines of the Kansas City Hyatt Regency Walkway incident of 1981....

 

[rwdenney]

Pontiac428, below are my thoughts, and I would consult the manufacturer for their thoughts if cutting holes are required.

View attachment 506734

Lighter than what I was suggesting, and should be plenty strong. It avoids even the harmless screw holes in the flanges (and those are harmless, otherwise the flooring, which is screwed into the top flange, would be a problem). Those plates on either side of the web should really extend nearly to the flanges as drawn. I'd also be tempted to run some beads of polyurethane construction adhesive to glue them to the webs. A few screws to hold them together up against the web while the glue sets and you drill the hole for the hanger bolt won't do any harm.

Rick "hoping the barn door track material is heavier than what is drawn" Denney

 

[rwdenney]

A leaning building..... Interesting, I was thinking more along the lines of the Kansas City Hyatt Regency Walkway incident of 1981....

I watched the Stratosphere in Las Vegas being constructed about the time they were a hundred feet up and discovered one of the legs was aiming the wrong direction. Even now you can see the kink in the south leg where they corrected the mistake. For a while, I kept a mental picture of a circle on the Las Vegas map of radius equal to the height of the tower ("Stupak's Tower", as we knew it then) and felt uncomfortable inside that circle. But it turned out that the 300-foot-tall sign originally installed in front of the Las Vegas Hilton (now the Westgate) on Paradise, which toppled in a microburst a couple of months after it was constructed, was the real problem. (The word "sign" is grossly inadequate to describe the structures used as such in front of hotels in Las Vegas.) They were building things in Vegas so fast that I kept thinking of that walkway in Kansas City.

(Those sorts of disasters seemed to follow Mr. Stupak, whose story is quintessentially Las Vegas. His first casino on Las Vegas Boulevard burned a couple of months after he opened it, and the sign in front of its replacement blew down in a windstorm a few years later.)

Rick "engineer of record for a large public works project in Las Vegas about 30 years ago" Denney