Automated Fixtures Hanging moving lights with c-clamps

Speaking of terminology, never heard of "gravity clamp." Do you mean trigger clamp?

I think so. I first called them trigger clamps before anyone said to me "that's a gravity clamp." Global Truss Trigger Clamp TRIGGER CLAMP B&H Photo Video But most people call them "gravity clamps" even though most mfg. call them trigger clamps. Just like people call 3 pin xlr cables "dmx cables." Differences in terminology will always be present in this industry. And I'm sure that the same issue occurs in most others. When I worked in restaurants we had "china caps" "chinoise" and "cone strainers" which are all exactly the same thing.
 
I think so. I first called them trigger clamps before anyone said to me "that's a gravity clamp." Global Truss Trigger Clamp TRIGGER CLAMP B&H Photo Video But most people call them "gravity clamps" even though most mfg. call them trigger clamps. Just like people call 3 pin xlr cables "dmx cables." Differences in terminology will always be present in this industry. And I'm sure that the same issue occurs in most others. When I worked in restaurants we had "china caps" "chinoise" and "cone strainers" which are all exactly the same thing.

No I'll post pictures when i get the chance.
Actually the sure clamp is what I am talking about. Thanks to gafftaper and the wiki.
 
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No I'll post pictures when i get the chance.
Actually the sure clamp is what I am talking about. Thanks to gafftaper and the wiki.

Sure clamps? You mean these? Sure Clamp (ain't google wonderful?)

What a person means when they use a term is partly a function of where they're coming from. I'd never heard of a sure clamp before, so that's the first thing I found.
 
...But most people call them "gravity clamps" even though most mfg. call them trigger clamps. Just like people call 3 pin xlr cables "dmx cables." Differences in terminology will always be present in this industry. And I'm sure that the same issue occurs in most others. ...
But that doesn't make the "wrong" people right, now does it?:evil:

Many people call a socket a base, a lectern a podium, a fixture's bail (or bale) a yolk, an adapter a turnaround, and so on. It's the duty of those who know better to correct those who don't. (Unless it's the boss who's using the wrong term--in that case just smile smugly, silently regaling in one's perceived superiority.)

See also the thread http://www.controlbooth.com/forums/question-day/21787-interchangeability-terms.html . Be careful out there!
 
And for the record, there's nothing inherently wrong with using any c-clamp to hang a scanner or moving-head fixture, other than the truss/pipe issue.

I would argue that there definitely is something wrong with using C-clamps for movers. C-clamps are designed to hold a static load, not a moving load. Movers can create a lot of torque, in a lot of different directions, in a very short period of time. C-clamps were not designed to handle those forces. Yes a C-clamp probably isn't going to break. But if it does, and someone gets hurt, what will the lawsuit be like? Who chose to use the wrong type of clamp? You did. I don't want to be anywhere near that lawsuit or the injured person. It's not worth the risk.
 
I would argue that there definitely is something wrong with using C-clamps for movers. C-clamps are designed to hold a static load, not a moving load. Movers can create a lot of torque, in a lot of different directions, in a very short period of time. C-clamps were not designed to handle those forces. ...
Let's all be sure to mention that to ETC.
We use half-couplers on our MLs, except for the S4 Revolutions which were designed to use C-Clamps. Ironically, the Revs are heavier than the other MLs. Haven't had a problem with either.
Emphasis added.

FWIW, a Revolution base fixture weighs 74 pounds; additional modules add 2-10 pounds each. The OP's Robe Spot 250XT weighs 41 pounds.

Given an unlimited budget, I would exclusively use City Theatrical's Tee Slot for all movers; but failing that, I'm pretty happy with the Mega-Claw.
 

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Interesting because ETC apparently has a seperate clamp with the part code of RPC that it specifies be used with the Revolution. Available from such companies at Full Compass. ETC/Elec Theatre Controls RPC Snap Clamp, Hanging Clamp | Full Compass
Since photographic evidence of this creature seems be elusive, perhaps a representative of ETC can confirm or deny whether the ETC RPC resembles this:
proxy.php

Snap Clamp for 2” Pipe
which looks awfully similar to a trigger clamp.

There's another type of clamp, I think by a European manufacturer (not Doughty or TUV), that might be called a snap clamp. It resembles a quick-release half-coupler, but I can't think of the name or find any pictures. Anyone know what I'm referring to?
EDIT: This is what I was thinking of, but I'm sure I've seen similar by another manufacturer.
 
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There's another type of clamp, I think by a European manufacturer (not Doughty or TUV), that might be called a snap clamp. It resembles a quick-release half-coupler, but I can't think of the name or find any pictures. Anyone know what I'm referring to?
EDIT: This is what I was thinking of, but I'm sure I've seen similar by another manufacturer.

Yeah your not crazy, I've seen something like that that wasn't made by them.
 
EDIT: This is what I was thinking of, but I'm sure I've seen similar by another manufacturer.[/SIZE]

I've seen those ONCE and I really didn't like them, but that was before the trigger clamp got popular. The problem with them IMO is that they don't hang on truss by themselves. Until you lock them in, they require somebody(bodies) to support them. The up side of that is that you can't forget to lock them. A trigger clamp can be left unsecured. Of course, if no one double checks the fixtures and safeties before a truss is flown out you probably have bigger problems than one loose fixture.
 
I know this an old thread but I am looking at getting the mega-claws andam nervous because on their website: Mega-Claw
It says it fits 1.9" to 2" OD pipe. I have pipe ranging from 1.75" to 2" OD and would like to be able to use with all of them. Has anyone used these for pipe smaller than 1.9" and how did they do? Thanks in advance!
 
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The 1.9-2" OD is just for the variance with steel and iron 1 1/2 pipe. Most steel pipe is more around 1.9 while some cast iron is close to 2.0. I have never seen a 1.75" OD pipe, not that it does not exist, most 1 1/4" pipe is more around 1.65"OD.
 
I know this an old thread but I am looking at getting the mega-claws andam nervous because on their website: Mega-Claw
It says it fits 1.9" to 2" OD pipe. I have pipe ranging from 1.75" to 2" OD and would like to be able to use with all of them. Has anyone used these for pipe smaller than 1.9" and how did they do? Thanks in advance!
Take a look at this thread http://www.controlbooth.com/forums/stage-management-facility-operations/28428-new-school-2.html starting at post #64
Another clamp to look at is this one :
Versi-Clamp
 
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