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[Dick Rees]

Adam Whetham wrote on Sun, 30 March 2008 11:29

Brad Weber wrote on Sun, 30 March 2008 10:45 Adam, I'll let those who know rigging correct me if I'm wrong but from my very limited understanding that doesn't look like a very good example.  With the exposed thread and the load likely coming at 90 degrees to the direction of the eyebolt (unless you pullback is off to the sides), I believe that essentially has a very diminished load capacity.  The eyebolts that Mackie or ATM provide are threaded for only part of the length so that they can be screwed in tightly and then have a thickened shank where they extend. For a pull back I really don't think it matters, we use the short guys on the top for the load bearing points. if the pull back breaks/rips out, i still have the two on the top to hold the weight of the cabinet. Yes it might not be fully right in some people's eyes but for a 55 pound cabinet its as safe as I could think it could be. I've hung these hundreds of times with these eyebolts and have yet to have a failure. The eybolt is screwed in as tight as it can go without busting the plastic. (If you ever take a 450 apart the flyware is not that gloriouse in the first place.) Not saying it might be wrong, but I trust my numbers and track record with these.

Adam....

Do I understand correctly that you are flying these Mackies with eye bolts screwed into threaded fittings on the tops of the speakers?????

DR

[Mac Kerr]

Dick Rees wrote on Sun, 30 March 2008 14:37

Do I understand correctly that you are flying these Mackies with eye bolts screwed into threaded fittings on the tops of the speakers????? DR

You mean the way the manufacturer designed and recommends? Maybe you meant to say "unrated" eye bolts.

Mac

[Adam Whetham]

Dick Rees wrote on Sun, 30 March 2008 13:37

Adam.... Do I understand correctly that you are flying these Mackies with eye bolts screwed into threaded fittings on the tops of the speakers????? DR

Yep, Don't know how else they would fit in....

[Dick Rees]

Adam....

The reason I asked about the loading of the speakers on the top of the cabinet is that I've always understood the proper way was to have the load bearing points at the bottom of the cabinet.  If Mackie designs it that way, so be it.  It's their funeral.  Other companies (my main reference is EV) require the load be borne either from the bottom or distributed over the entire cabinet via specially designed fly brackets.

If you've never had a failure yet, good on you.  I do not do it that way as (no matter what the mfr says) I do not trust a load to hang safely for an extended period of time with the threads carrying the weight.  And I'm not primarily concerned with liability.....the lawyers can figure that out.  I just don't ever, ever want a load coming down on anyone.

[Mac Kerr]

Dick Rees wrote on Sun, 30 March 2008 22:36

The reason I asked about the loading of the speakers on the top of the cabinet is that I've always understood the proper way was to have the load bearing points at the bottom of the cabinet.  If Mackie designs it that way, so be it.  It's their funeral.  Other companies (my main reference is EV) require the load be borne either from the bottom or distributed over the entire cabinet via specially designed fly brackets

Some speakers are designed to be flown with other speakers hung below them. In this case the load is likely to be far greater than the weight of a single box. That is why many speakers have internal steel framework. the Mackie 450 doesn't have matching points on the bottom, it can be flown 1 deep only. It doesn't matter where the load is carried if the system is engineered to be safe when used as directed,

Mac

[jeffhtg (Jeff Kenney)]

quality control overseas is debatable.. thats why it is my companies policy to only use U.S. made steel.  My original complain t was a manufacturer making non standard rigging points - and then not even supplying a rigging kit that fits.

the book says "... are fitted with ten rigging points as shown in the diagram below. These are M10 inserts. M10 threaded eyebolts (M10 x 1.5 mm x 20mm) are available to fit these...." okay.. im just throwing it out there.. but a 20mm M10 eyebolt DOES NOT fit the back pullback point as per the manual.

Use what you want.. I wont stand under it in the future.

[Mac Kerr]

jeffhtg (Jeff Kenney) wrote on Sun, 30 March 2008 23:06

quality control overseas is debatable.. thats why it is my companies policy to only use U.S. made steel.  My original complain t was a manufacturer making non standard rigging points - and then not even supplying a rigging kit that fits.

When they built the Javits Center in NYC, which is built with a steel tube frame with round nodes, like tinker toys, no US steel company could provide acceptable steel for the nodes. They were all imported from Japan. It was a scandal here that no US steel had been found acceptable.

Mac

[jeffhtg (Jeff Kenney)]

Mac Kerr wrote on Mon, 31 March 2008 04:10

jeffhtg (Jeff Kenney) wrote on Sun, 30 March 2008 23:06 quality control overseas is debatable.. thats why it is my companies policy to only use U.S. made steel.  My original complain t was a manufacturer making non standard rigging points - and then not even supplying a rigging kit that fits. When they built the Javits Center in NYC, which is built with a steel tube frame with round nodes, like tinker toys, no US steel company could provide acceptable steel for the nodes. They were all imported from Japan. It was a scandal here that no US steel had been found acceptable. Mac

and that very well could be crooked politics.. I don't know anything about that. I don't have problems with importing most things.. but I certainly have seen WAY to many defunct products from China to risk human lives on it until there is a little more standardization of some sort.

[Jens Bacher]

Chinese steel -with copper ferrules...


http://www.safetyphoto.co.uk/llnl/cosby%20safety.htm

[Jason Lavoie]

Jens Bacher wrote on Tue, 01 April 2008 19:03

Chinese steel -with copper ferrules... http://www.safetyphoto.co.uk/llnl/cosby%20safety.htm

with all due respect, I don't see anything in that article that indicates the steel came from china.
just because it's junk doesn't mean it didn't come from the grand ol US of A
and even if it didn't, it doesn't mean that it wasn't designed, ordered, or orchestrated by someone from the US

you guys are paranoid about the chinese.

Jason