Conventional Fixtures Pan Bolt Discussion

Re: New Lighting Blog Series: Types of Units

Yes, if your space has clamps with shafts that DO NOT have a safety lip to prevent it from free-falling when loosened, I strongly suggest getting them replaced.

Very rarely {i.e. never} have I seen a C-clamp with out some sort of saftey mechanism on the shaft. If you find one in your inventory it should be replaced immediatly. One should not make it into the air because its a defective C-clamp at that point.
Okay, I strongly discourage my techs from panning the unit with the set screw. It is too easy to break the head off, it is very easy to pull all the way out and strip it putting it back in, it is easy to create grooves in the shaft which effect focus, sometimes it takes too long to het a wrench on it when you can do a yoke bolt focus with just your hands, eventually the bolt will not tighten fully anymore.

There is a laundry list of reason not use it for focus.
Breaking the head off a pan nut is an excuse IMHO. When you focus using the yoke bolt you run into the same issue that Gern's broken shafts create. Too often electricians don't tighten them down properly and they can work their way loose.

In the past 15 years I've never had an issue with a grooved shaft affecting focus whether I was the electrician or the designer.

For every reason not to use the pan bolt theres a reason not to use the yoke bolt.
 
Re: New Lighting Blog Series: Types of Units

First off I have never broken a pan bolt in my 11 years of focusing, if you break one your probably doing it wrong. We have very few of the square head pan bolts left in the building these day, we have been slowly phasing them out and replacing them with t-handles like those linked below. Makes it easy to focus without tools, and almost impossible for some idiot to break one. Most of us also use a mega wrench when tightening up the clamp bolts, again gives you enough leverage to tighten the bolt down, and not enough to break it.

T Bolt for Pipe Clamp
 
Re: New Lighting Blog Series: Types of Units

This debate could so easily be solved if everyone would simply switch to using these:
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Mega-Clamp

However, there must have been market demand (Lord knows why) or the manufacturer would not have started offering this
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http://www.thelightsource.com/products/16/view
 
Re: New Lighting Blog Series: Types of Units

We have very few of the square head pan bolts left in the building these day, we have been slowly phasing them out and replacing them with t-handles like those linked below. Makes it easy to focus without tools, and almost impossible for some idiot to break one.

T Bolt for Pipe Clamp
Whenever my local company does an install, they have those T-bolts you linked to, and a Mega Combo Wrench on everything. It's nice to work in theaters they installed. :)
 
Re: New Lighting Blog Series: Types of Units

I didn't like those when I used them...I don't really know why, but I prefer these:
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They just seemed more secure.

EDIT: Or, we could just avoid the fuss altogether, and switch to this:
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"Are you sure that will hold up a Bad Boy?" "Of course...i think..."
 
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Re: New Lighting Blog Series: Types of Units

I didn't like those when I used them...I don't really know why, but I prefer these:

They just seemed more secure.

You know why you don't like the other ones? Because they are a pain to use! You have to unwind the bolt so much farther to get a light off the pipe than you would with a normal c-clamp!
 
Re: New Lighting Blog Series: Types of Units

I didn't like those when I used them...I don't really know why, but I prefer these:

They just seemed more secure.
Well, they aren't. What's the load rating stamped on yours? Oh right, there isn't one. See also http://www.controlbooth.com/forums/lighting-electrics/6726-c-clamps-rated.html . I swear if it weren't for c-clamp s and FELs we'd have nothing to talk about.
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See this post.
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...You have to unwind the bolt so much farther to get a light off the pipe than you would with a normal c-clamp!
Sounds like a good safety feature to me! (Speaking as someone who is (usually) paid by the hour.)
 
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Re: New Lighting Blog Series: Types of Units

For what it's worth, the only two or three pan bolts I've ever broken have been on Altman clamps, old rusty abused Altman clamps. Go figure.
 
Re: New Lighting Blog Series: Types of Units

I go betwixt liking and despising the Mega Clamp. While I like that they are extremely unlikely to manage to finagle their way off the pipe, and that the lower clearance they have around them allows them to fit into tighter spaces (like the grid in the black box of my university before we evenly spaced all pipes at 1 foot apart), I get really darned tired in my arm, wrist, and hand after going those few extra spins on each clamp on a long day. Or, I will sometimes miss having that set screw as a second way to adjust pan when someone has really WRENCHED on the yoke bolt hard (usually the rental shop, surprise surprise) or I really just can't get a good angle on the yoke bolt. Mostly just the wrenching, though.
 
Re: New Lighting Blog Series: Types of Units

For what it's worth, the only two or three pan bolts I've ever broken have been on Altman clamps, old rusty abused Altman clamps. Go figure.

Probably because they're so darned common! Are those clamps actually cast by Altman? Seems that there are so many clones out there with different (or no) names, that Altman probably just calls the factory and orders X amount with their name cast in to them. Heck, said company probably has the dies for most major manufacturers (and a blank for the "no names").
 
Re: New Lighting Blog Series: Types of Units

So it sounds like most people use the pan bolt for pan adjustments then? What I've always wondered - why isn't it a thumb bolt, so I don't need to reach for a wrench? It's not as though it needs excessive tightening.
 
Re: New Lighting Blog Series: Types of Units

Can I add that the "set screw" (or whatever you wish to call it) cannot be effectively used unless your units are hung with the C-clamp perfectly verical. If you were to hang your lights in a different way, for instance, vertically above the bar, sometimes the set screw isn't tightened down enough to prevent it from sliding when I hang the light. This is even when the screw was tight (apparently not that tight) before the light was hung. (If this is an error I get because I'm simply doing something incorrectly, can someone correct me?)

My other big problem with them is that my speed wrench doesn't seem to fit the set screw on some of those older Altman-looking ones.

This debate could so easily be solved if everyone would simply switch to using these:
However, there must have been market demand (Lord knows why) or the manufacturer would not have started offering this
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Mega-Swivel

What is the point of having that screw there anyway? (Besides looking like it has one.) I like the mega-clamps better generally, but that's just silly.
 
Re: New Lighting Blog Series: Types of Units

Yep, multiple ways to do things, that is for sure!
Once upon a time I set a 407(Mole 1K fresnel) on a stand up around 7' from the floor. As I was trained, I did a strain relief loop in the cable then hooked it to the fixture using the built in cable rope. During focus Bo... Dicki.... went to the unit, wanted to tilt it up, and just pulled the power cord down. It didn't tilt up. When he look at the head and saw the cable wasn't just hanging free, he exploded screaming "Somebody doesn't know what the #@*! they are doing!" He was right of course: I didn't know that what I was doing was making it impossible for him to just yank on a power cord to change his focus...
See http://www.controlbooth.com/forums/lighting-electrics/19893-lighting-designers-vs-board-ops.html
Of course:
1 He is the designer.
2 He is respected by far for people than I am.
3 He makes way, way, way... more money than I do.
4 I will always still put a loop on a fixture when on a stand. More than one if it gets hung on a pipe, so as to be moved quicker.
Doesn't he know that he should really be using a paint roller with no pad? :) Sheesh!
 
Re: New Lighting Blog Series: Types of Units

What is the point of having that screw there anyway? (Besides looking like it has one.) I like the mega-clamps better generally, but that's just silly.

Because it does function, reading product description FTW.
 
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I have Hung lights in the most wily angles and the set screw does hold it there. I'm not sure what your doing wrong...

Sent from my ADR6300 using Tapatalk
 
I've had plenty of not tight enough set screws that have allowed a light hung upside down to slide up the shaft, and had to tighten it down. Also one of the last shows I did was fully mega clamped or O clamps
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also kind of a pain but when working with little clearance you've gotta get every inch you can.
 
I have Hung lights in the most wily angles and the set screw does hold it there. I'm not sure what your doing wrong...

Sent from my ADR6300 using Tapatalk

Even when its loose?

Seriously though. There comes a point in the focus session where hitting the light with a wrench seems to be just as good as actually focusing... During times like that Ill take the giant bolt thats easy to find and access over the tiny little thing commonly called the "F*** me bolt" by everyone I know. Never had a problem per se focusing with either. Usually I go with the one that is more convenient to use. I really wish we all used mega clamps tho. I agree with Derek. As a paid by the hour technician, Ill take the extra ten minutes it takes to screw the clamp to the pipe over a few scores of units. Thats like a case of beer just for using bigger screws on the clamp... However, I am totally down with the O clamp thing. As for T handles, I take them off first thing. Totally worthless and they work loose when someone decides to drive the front-end loader over the theater for a few days (our black box was underground). Then you get to use a wrench in a way that God never intended to try and get it to tighten or loosen correctly.

If a designer has a preference (realistically thats kind of a silly thing to have a preference over. Dont you provide a focus plot or do you expect nothing to change in the theater for a couple months/years? Seriously? Slash on a tour where it gets hit by a forklift every day? If you care about the method the LX guy uses to focus the instrument uses then you really need to pay more attention to the art and less you the giant head your carrying around.) Ill try and make it happen, but to heck if Im gonna hold a top hung unit up while doing some incredibly inadvisable thing to try and reach an instrument that some a** hat decided to hang in a totally inaccessible place up with one hand and use my legs to hold myself on to whatever is supporting me... Also if your pulling on the instrument's cable to focus it, I can see a couple problems. If thats your plan, get a loop of rope put on so as you can go both ways at least...
 

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