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[Bob Faulkner]

Generally, yes.  In fact, JBL requires it to suspend VerTec 48xx series loudspeaker bumpers (fly frames) but you should contact the manufacturer of your system to confirm any requirements for safe suspension.  Request specific brands and models numbers.  If they are unwilling to specify at that level you will need to look *very* carefully at the pin diameter to make sure it will fit in the suspension hole.

Get ready for some price shock when you go looking at C-M or Crosby Anchor shackles, esp in larger sizes.

Sounds good.  Thank you.  The frames I have look like maybe 1/32 space would remain if a 3/4" pin were used.  That seems rather tight.  Have not looked at C-M or Crosby yet; the McMaster-Carr brand (so far) looks affordable.

[Stephen Kirby]

If you are going to lift 600lb, the shackle should be rated at least 10x that, ie 6000 lb. Looking at the load tables steel and alloy are fine, but stay away from stainless steel ones.

Just curious, why would one stay away from stainless?  From my days sailing, there a tons of load rated stainless fittings in chandlery.  And the dynamic loads in a sailboat rigging are pretty serious.  Gybe ho!

[Tim McCulloch]

Just curious, why would one stay away from stainless?  From my days sailing, there a tons of load rated stainless fittings in chandlery.  And the dynamic loads in a sailboat rigging are pretty serious.  Gybe ho!

For a given shackle size, forged cast steel is stronger than stainless.

[Stephen Kirby]

For a given shackle size, forged cast steel is stronger than stainless.

Agreed, but he also said "alloy" is okay.  Which I took to mean aluminum.  And that is much weaker than stainless, especially 400 series.

[Rob Spence]

Agreed, but he also said "alloy" is okay.  Which I took to mean aluminum.  And that is much weaker than stainless, especially 400 series.

Where is alloy = aluminum ?

Most steel is an alloy


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[Tim McCulloch]

Agreed, but he also said "alloy" is okay.  Which I took to mean aluminum.  And that is much weaker than stainless, especially 400 series.

Carbon steel is an alloy (and Love is the Drug, according to Roxy Music).
https://www.amazon.com/gp/aw/d/B00OAW9IMK is Columbus-McKinnons most used entertainment rigging shackle and it's half the price of Crosby right now...

Make sure that every item used in your rigging and suspension systems is rated for overhead lifting.  A surprising number of shackles, turnbuckles and other hardware has "Not for overhead lifting or suspension of loads above people" somewhere in small print on a tiny tag.  Buy rigging and suspension products from vendors that understand entertainment - Sapsis Rigging, Fehr Brothers, Production Advantage, etc. The shackles you can buy at a home center, farm supply or towing & recovery shop are almost NEVER suitable for our uses.

[Mark Cadwallader]

Sounds good.  Thank you.  The frames I have look like maybe 1/32 space would remain if a 3/4" pin were used.  That seems rather tight.  Have not looked at C-M or Crosby yet; the McMaster-Carr brand (so far) looks affordable.

The pin on a 5/8" shackle is 3/4" diameter.  The 5/8" refers to the nominal diameter of the shackle body.  A 5/8" shackle is the standard size I see used in rigging for theatrical purposes; however, my experience is not nearly as extensive as other regular posters (like Mac).

[Stephen Kirby]

Where is alloy = aluminum ?

Most steel is an alloy


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He said "steel or alloy".  The term is most commonly used for aluminum alloy.  Alloy wheels vs. steel wheels.  Same as in climbing or sailing gear.  Maybe in bicycle frames due to the fancy Reynolds and Columbus steel alloys it might be used differently.

I only have one place where I hang anything and I bought the spansets and hardware from a reputable lifting supplier.  But I've often wondered about sailing hardware given that it's also seriously tested and rated, with similar safety implications.  Having had my butt hanging in a bosun's chair up the mast, I wouldn't have done it if I didn't trust the ratings and the manufacturers.

[Peter Morris]

We finally have our own flybars.  Lift points (down the center) are all 3/4" diameter.  Looking at McMaster-Carr at their lifting shackles (thanks to all who recommended them), looks like we can do 5/8" thick shackles.  Having used some shackles in the past, all seemed to be galvanized.

Is galvanized the best choice?  Or how about galvanized alloy steel?  The most we'll probably ever lift is 600 lbs.  Shows could be either inside or outside.  The galvanized shackles we've used seemed "cheap", but they never failed.  The screw pin on these took some time to get in and out (seemed to stick).  Wondering if the galvanized alloy steel would be better...?

A couple of minor points;

•   All steels are alloys, alloys of iron.
•   It does not matter if your shackles are black steel, stainless steel or galvanised steel – what matters is that they have been rated in accordance with a standard. (I don’t know what the US standard is)
•   The rating is usually stamped on the shackle
•   As Geert Friedhof mentioned, the rating does not provide a suitable factor of safety for lifting near or above people.
•   Shackles depending on what standard they have been tested to will have a factor of safety of about 4.5:1 to 6:1 - it’s different in different parts of the world
•   As a rule of thumb you need about 10:1 for flying near or above people – i.e. only lift half what the shackle is rated for
•   It is possible to buy cheap (usually galvanized) shackles that have no rating and are made out of  low alloy weak steel. They will not have a rating stamped on them – DO NOT use these.

[Geert Friedhof]

Steel vs alloy: when i refer to alloy i mean steel alloy, which has some elements added to it to make it up to 50% stronger than carbon steel, at a very high price.

For stainless steel: as far as i know all manufacturers advice against using stainless steel wires, chains and shackles for overhead use, If not forbidden by law, even if the WWL is high enough.

[ProSoundWeb Community]