Holely C-clamp Batman

I love the Safer Sidearms ... for hanging movers. Or speakers. They're a little overkill for conventionals, especially if (as some tours do) you prep the boom and sidearms, and then move it as a unit.
 
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Image from techtheatre reddit.

Okay everyone, let's all post pictures of failed c-clamps.

A rough CB search returns
https://www.controlbooth.com/threads/unsafe-safety-cables.26798/#post-237602 , and

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https://www.controlbooth.com/threads/are-c-clamps-rated.6726/page-3#post-258246

Now post pictures of failed TheLightSource aluminum Mega Clamp.
 
Interesting to look at those failures. The added hole could have been:
1. to spread force and make this kind of failure less likely (I doubt it)
2. to add a point to run a safety that would prevent catastophe in this kind of failure (but the hole makes it more likely that the clamp would break at the hole, negating this theory)
3. Give us all something to talk about here on CB. (Any PR is good PR)
 
I'm sad that we have no Altman folks on the board

But we should take this as a challenge. When you go to a trade show, ask the Altman rep what's the deal with the hole?
 
Interesting to look at those failures. The added hole could have been:

2. to add a point to run a safety that would prevent catastophe in this kind of failure (but the hole makes it more likely that the clamp would break at the hole, negating this theory)

I don't see how a hole for a safety there makes it any safer. It's right along or below the line that clamps seem to break. So that part of the clamp would still be attached to the light and get caught by the lights safety cable. It's the top part of the clamp that is probably most likely to still fall to the deck and hit someone.
 
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If I didn't know any better, I'd say that hole is for hanging the clamp on a peghook. Actually, I don't know any better. I just doubt that's what it's for.

Maybe a handy place for tie-lining a fixture whip?
 
If I didn't know any better, I'd say that hole is for hanging the clamp on a peghook. Actually, I don't know any better. I just doubt that's what it's for.

Maybe a handy place for tie-lining a fixture whip?
I'm still guessing it's for hanging with conveniently reasonable speed, security and electrical conductivity for a quick trip around the powder coating line. Powder coaters want to be able to hang and extract items quickly on the fly, with one hand whenever possible and the line still moving, to make reasonable electrical contact and not fall off into the over spray where things need to be raked out and collected prior to recycling as much of the unused overspray as possible. You've got to know powder coaters recycle as much black as they can manage whereas they need to invest somewhat more time, effort and care into recycling more pristine colors such as polar white or any of the pastels where subtle blemishes would be more readily apparent. We had one coater in our area who'd bid much lower pricing if you'd take your products in black, ideally the precise black he was primarily running. He liked to keep one of his lines running black 24 / 7, just keep loading in the products and raking in the money.
I also concur with asking someone readily approachable like Rich Dale at Altman and 'strong arming' their smiling rep's at the next major show if an honest answer isn't forthcoming in a timely period.
Toodleoo!
Ron Hebbard.
 
Just a quick heads up, Rich Dale hasn't been at Altman in at least a year. He's over at Morpheus now. Probably still has some good contacts in Altman.
Thank you. My last e-mail from Mr. Dale was dated Friday February 19th 2016 thus you may be a little off when you say "at least a year" as he was definitely writing me on behalf of Altman at that point. Close still wins the cigar.
Thanks again.
Toodleoo!
Ron Hebbard.
 
A lot of discussion over a hole in a c-clamp. I saw Bob Altman at a product demo a couple weeks ago. I don't know if he would know. He gave me a t-shirt. I was happy. My guess is the hole is a place to clip a safety cable when the fixture is not hung so it isn't dangling on the floor.
 
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Complete with a 220.46(!)-pound SWL. Supposedly made from aluminum instead of cast iron, so not precisely as silly as the Altman hole would be if it indeed was intended for safety cables. Probably a benign reason it exists but that doesn't mean it won't be used as an attachment point for safety cables -- which I would be inclined to think makes it more of a liability to have it there than to not.
 
I can't imagine how Altman is doing this that the hole doesn't somehow decrease the structural integrity of the clamp by a significant margin. This is their 510-HD heavy duty clamp.

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Anyone ask their Altman rep. yet? Do I need to in being busy with other projects at the moment? I would also consider this to be within the web of the clamp flute and not structurally a problem. Perhaps a way to hoist the fixture up to a batten in the least having to lift the light type of way? Perhaps a tie off for dressing the wire electrical cable whip? I would say ask the manufacturer, and also ask them why they are not part of the forum in otherwise directly answering them and advertising.

Great photos above, but larger holes to fit a safety cable. Interesting though that HD clamp hole in size verses concept of the HD clamp. Safe enough no doubt, but a lot of material removed in the meat area without expanding the size.

Back to school, a hole should be no closer to the edge than 1/2 the diameter as a rule. But these are cast clamps and seemingly wider in compensating.
 
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I can't imagine how Altman is doing this that the hole doesn't somehow decrease the structural integrity of the clamp by a significant margin. This is their 510-HD heavy duty clamp.

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Personally, I'd far prefer the safety to loop over the pipe / supporting structure. I suppose "they" can loop it through the clamp as well but it's feeling like more of a time waster than a benefit. I can understand this more with machined aluminum clamps and conveniently larger diameter holes in film / video location shoot / field applications but I'm yet to envision any serious benefits with dozens of instruments lined up on 18" centers in neat rows on fly-pipes in theatrical touring and / or 'house plot' situations. I'm probably just being my decrepit 'stick in the mud' self but that's my personal opinion.
Possibly slightly of benefit when when wrapping your Zetex protective borders over fly-pipes and tying them solidly into the clamps as a way of potentially maintaining better trims rather than simply tying your protection directly to the pipe but I'm really straining my brain to come up with that one. I'm still sticking with my powder coating theory.
Edit: Corrected a typo.
Toodleoo!
Ron Hebbard.
 
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Is it possible that if you overtighten the clamp that the portion on the outside of the hole will buckle and warn you that you have a weakened clamp before it ends up shattering?
 
I can't imagine how Altman is doing this that the hole doesn't somehow decrease the structural integrity of the clamp by a significant margin. This is their 510-HD heavy duty clamp.

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Think of a crinalted beam - like at United terminal at OHare. It's the edges that do the work.

PS correction - castellated, not crinalted which was to be crennalated. It was late, had driven 9+ hours since early, including several in bad snow.
 
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Anyone ask their Altman rep. yet? Do I need to in being busy with other projects at the moment? I would also consider this to be within the web of the clamp flute and not structurally a problem. Perhaps a way to hoist the fixture up to a batten in the least having to lift the light type of way? Perhaps a tie off for dressing the wire electrical cable whip? I would say ask the manufacturer, and also ask them why they are not part of the forum in otherwise directly answering them and advertising.

Great photos above, but larger holes to fit a safety cable. Interesting though that HD clamp hole in size verses concept of the HD clamp. Safe enough no doubt, but a lot of material removed in the meat area without expanding the size.

Back to school, a hole should be no closer to the edge than 1/2 the diameter as a rule. But these are cast clamps and seemingly wider in compensating.
I did - Jason and Nic - no response yet.
 
Well, I got a reply, and as I suspected - to safety the clamp - likely for Disney parks. They require every accessory to be safetied - even gel frames when I worked on a project there. It does seem like from where failure occurs that the hole should be in the other end, as the end with the hole will probably stay with the yoke.
 
I have personally seen many clamps "fail" that were inappropriately clamped on 1" pipe or slipped off a truss condom. In this case user error was at fault. Given the ridiculously rare incidence of clamps actually shattering (worked in event lighting for a decade and in lighting for over 20, I've seen one actual break and tossed a few for cracking/stretching etc. as opposed to dozens for rust) these holes may be targeting a more common failure (slipping off the pipe) while keeping the cable as much out of the way of the user as possible.
 
I have personally seen many clamps "fail" that were inappropriately clamped on 1" pipe or slipped off a truss condom. In this case user error was at fault. Given the ridiculously rare incidence of clamps actually shattering (worked in event lighting for a decade and in lighting for over 20, I've seen one actual break and tossed a few for cracking/stretching etc. as opposed to dozens for rust) these holes may be targeting a more common failure (slipping off the pipe) while keeping the cable as much out of the way of the user as possible.
You've worked "worked in event lighting for a decade and in lighting for over 20"? Over 20 decades!!!? At 200 years plus, just how old are you and when does your deal with the devil expire?
Toodleoo!
Ron Hebbard (Who was feeling old until you posted)
 

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