ATM Flyware double stud fittings - Load ratings and angles?

S

Simon Coffin

Sophomore
Mar 2, 2011
133
1
18
State College, PA
www.medianengineering.com
Folks,

I looked at the RCF 4Pro-6001 a few days ago, nice speaker if it fits your needs by the way, but didn't understand why the L-Track fittings are mounted on the sides of the cabinet and horizontal. I had always thought that single and double stud fittings were desgined to be used under tension and should never be loaded sideways (bending force) which appears to be the only way to suspend this cabinet.

None of the documentation I could find gave specific Working Load Limits at angle for the stud fittings. http://www.allenproducts.com/pdf/components_old.pdf from Allen Products does have the 90 degree WLLs as well as ratings for the L-Track itself which shows a significant derating at 45 degrees.

Can anybody shed some light on load ratings for stud fittings and how the 4Pro-6001 should be correctly suspended?

Cheers,
Simon
 
Re: ATM Flyware double stud fittings - Load ratings and angles?

Simon Coffin said:
Folks,

I looked at the RCF 4Pro-6001 a few days ago, nice speaker if it fits your needs by the way, but didn't understand why the L-Track fittings are mounted on the sides of the cabinet and horizontal. I had always thought that single and double stud fittings were desgined to be used under tension and should never be loaded sideways (bending force) which appears to be the only way to suspend this cabinet.

None of the documentation I could find gave specific Working Load Limits at angle for the stud fittings. http://www.allenproducts.com/pdf/components_old.pdf from Allen Products does have the 90 degree WLLs as well as ratings for the L-Track itself which shows a significant derating at 45 degrees.

Can anybody shed some light on load ratings for stud fittings and how the 4Pro-6001 should be correctly suspended?

Cheers,
Simon
Click to expand...

I think that information should come directly from RCF and supported by an engineering drawing with ratings, bearing the stamp of a registered professional engineer.
 
Re: ATM Flyware double stud fittings - Load ratings and angles?

Hey Tim,

Agreed. RCF's website doesn't have any specific documentation for flying this cabinet beyond saying that if they are suspended on top of each other, the top one should be upside down so the mid horns are together. Their flying kit includes 4 double stud fittings with rings, but no documentation.

Would a dealer have access to more specifics?

Ciao
Simon
 
Re: ATM Flyware double stud fittings - Load ratings and angles?

Simon Coffin said:
Hey Tim,

Agreed. RCF's website doesn't have any specific documentation for flying this cabinet beyond saying that if they are suspended on top of each other, the top one should be upside down so the mid horns are together. Their flying kit includes 4 double stud fittings with rings, but no documentation.

Would a dealer have access to more specifics?

Ciao
Simon
Click to expand...

We're DB Technologies/RCF dealers and don't have any information beyond what's in the manual and on the web. RCF's New Jersey office has been quick to get info from Italy, though. My guess is that RCF has at least calculated WLL and probably has pull-tested representative samples.
 
Re: ATM Flyware double stud fittings - Load ratings and angles?

Tim McCulloch said:
We're DB Technologies/RCF dealers and don't have any information beyond what's in the manual and on the web. RCF's New Jersey office has been quick to get info from Italy, though. My guess is that RCF has at least calculated WLL and probably has pull-tested representative samples.
Click to expand...

The club I am in on weekends has a pair of QrX on each side hung from rings in the l track. They have no splay and no where near enough downtilt. I have been encountering the same lack of any reasonable information about torque on the l track. I have a feeling both of my initial email queries to EV and polar focus are in dead email bins somewhere.
 
Re: ATM Flyware double stud fittings - Load ratings and angles?

Hey Gents,

Just called RCF in New Jersey and spoke with a real live informative and knowleadgeable human being. Quite the surprise.

The latest version of the 4Pro-6001 have the L-Tracks mounted top and bottom which makes a lot more sense. They specify that each fitting is rated to 100kg/160lb but do not provide any angles. Two cabinets can be flown one under the other and will stay within limits. The wording is vague, probably on purpose to give them some wiggle room should an idiot try to shift the blame. I'd much prefer some specific guidance but doesn't look like that is going to happen.

Cheers,
Simon
 
Re: ATM Flyware double stud fittings - Load ratings and angles?

Simon Coffin said:
Hey Gents,

Just called RCF in New Jersey and spoke with a real live informative and knowleadgeable human being. Quite the surprise.

The latest version of the 4Pro-6001 have the L-Tracks mounted top and bottom which makes a lot more sense. They specify that each fitting is rated to 100kg/160lb but do not provide any angles. Two cabinets can be flown one under the other and will stay within limits. The wording is vague, probably on purpose to give them some wiggle room should an idiot try to shift the blame. I'd much prefer some specific guidance but doesn't look like that is going to happen.

Cheers,
Simon
Click to expand...

I expect they have arbitrarily derated the hardware for some reason. According to that Allen Products link the only stud fittings permitted for overhead use have a 500lb vertical WLL and a 400lb 90º WLL. The track itself is rated at 900lb vertical and 300lb at 45º with those double stud fittings. Of course it is possible to use fittings not rated for overhead use, and they derate to 160lb at 90º, but the track derates to 150lb at 45º with those single stud fittings.

Mac
 
Re: ATM Flyware double stud fittings - Load ratings and angles?

I just got off the phone with polar focus. According to them, the reason they use the studs with rings rather than threaded studs is the cost, not the strength of a side pull on the l track.



Sent from my DROID RAZR HD
 
Re: ATM Flyware double stud fittings - Load ratings and angles?

Positioning the track like that is a cost-dodge against running additional internal metal.

The track should be on top and bottom panels if they think array flying is a regularly used option. If the original config had sported vertically oriented track it would have shown a somewhat better grip on real-world usage.
 
Re: ATM Flyware double stud fittings - Load ratings and angles?

Hey Mac,

I suspect RCF has derated the specs not because of a weakness in the hardware, but because of a structural limitation in the cabinet. While the flytrack is probably rated to 900lbs as shown in the Allen Products pdf, the speaker cabinet may have limited or no steel reinforcement between the top and bottom tracks, and becomes the weak link in the chain.

Now that I think about it, the JBL Rigging Guide used similar descriptions of a max load per point. Since the top points are the most heavily loaded, as long as they are within limits, everything underneath is ok.

Cheers,
Simon
 
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