Spot Light falling

krhodus

Member
Today I was adjusting the heigh on an Altman Commet. I didn't realize how loose the knob on the yoke was, and so the whole light fell on top of me. The intersting part was I didn't feel the gash it left in my head. I only noticed it afterwards when talking to our TD and saw blood on my hands. By then it was really bleeding. Our SM cleaned me up while lecturing me on why did I have to do this and why didn't I feel any pain. I was forced by the TD to leave and get it looked at. That was a long fight. I believed that tech came before a little cut. He didn't. He ended up forcing me to sit down or be banished from the theater, and he went and got my stuff and watched me until I left. In the end he won, I ended up getting 4 stitches to close the wound. Luckily it was only the cornor of the light that hit my head.

Kevin
 
simply put, safety always comes first, it may look minor, but it can be a lot worse...kinda when i broke my ankle and thought i just pulled something...that was bad. anyway, you need to remember that your wellbeing and saftey come before everything. techs joke that theatre is before everything, even safety, but we know, we just wont admit, the fact that thats really not true. safety is the most important thing of them all. im not blaming you for dropping the light, ive done it to. we make mistakes, just whenever you get hurt, get the neccesary and above neccesary-seeming care as quickly as possible.
 
If you would like I can forward it to Altman if you specify further what went wrong. Perhaps in some future models it will get improved so it does not happen again. I'm frequently known to play a role in upgrades or opinions of them with them - or at least to make my opinions known as ifsuch a thing about me were in doubt.. My latest project is the mini cyc. Uhm,... Hello!

Glad to see the knock upon the head did not improve anything. Still when the TD says to go, you go it's just not your rear on the line.

What did go wrong that in general caused it to fail that those no matter the brand should watch for?
 
Wounds to the head are funny like that. I had a bike fall from it's storage rack in the rafters of my shed on to my head and I completely didnt feel any cut, I could tell something was wrong by the look on my dad's face though. It took me about 5 minutes to feel it, but when I did it was bad! I had to get rushed to the hospital and get a ton of stiches for it, which wasnt fun at all! The moral of the story: head injuries can be alot worse then they feel! Dont underestimate them!! (or anyother injury for that matter!)
 
Thought I'd give my tuppence on this. I'm a RYA Sailing Instructor, and as such have to hold a valid 1st Aid Certificate. The rule for any head injury is to...
get to hospital and have it checked out, or brain damage could result, no matter how small the apparent injury

(Stops reading from 1st aid manual)

Heh heh! Yeah. Just play it safe, and like everyone else said, bear in mind it's not just your arse on the line if something goes wrong.

8)
 
I too often work on an Altman Commet follow spot. The bolts on the yoke don't every seem to stay on. Also, we still use the orriginal stand that came with the light, and those are not the best stands- Nothing on them every tightens right and it always wobbles. --but getting back to the yoke issue-- I almost sent the spot over the edge of the balcony when the bolt on the right side of the yoke came out before a show when I was checking the light. Luckly, with the help of the left blot, I stopped it from tipping-- that was not a cool night when i look back, just about everything went wrong, but that is another story....
 
Beyond the above two incidents, I'm not sure if I can see any way to improve the fixture beyond what methods are used in prepping it for a show and what might be a nut that might be better as a different part if not just replaced if it fails as similar to a stripped screw on something that gets removed a lot should you de-yoke the fixture.

If of any help, I don't see any problem with the parts used on the fixture, only in it not noticed to have failed before use of it. Sorry you got hit, but often something failing is a wake up call to something needed to be added to the before used checks. Definately something to inspect it would seem.

From what I see from the parts manual, one side has a knob (12-0020-25), washer (32-FW375), and screw 24-0225). I expect that given the hand knob, this is the side that did not come un-done since knob adjustments are something the end user is charged with making tight or loose.

The other side has what seems by PDF picture like a nut (31-HF500), cone washer (32-FW500) and screw (30-HT50016). (Left my actual parts descriptions in saying what they are at work.)

Not a lot of room for a longer bolt in the assembly thus if it is using a nylock nut, perhaps a thread deforming side lock nut might be a better option if the nylon locking nut came loose. Such nuts lock in a similar way but instead of using the nylon to prevent un-screwing, use a deformed thread to grab onto the screw attached to. Such nuts thus are not much effected by heat and how much used unlike the nylon. This nut given the fixture will not be removed from it's yoke. A thread deforming nut does just that in that it screws up the threads of the screw it is locking to. For the most part, it's a one time deal and if you remove it, the screw needs to be considered for replacement. Nylock nuts on the other hand don't damage the screw thread so if the fixture needs to be de-yoked, it might be a better option. Just keep in mind that this nut will need occasional replacement.

Should this fixture have it's nylon locking nut removed a few times or get too hot, given it is only nylon it will grip less and less with time. The Nylock nut with heat or repeated tightening or movement can fail still as if a normal nut in not gripping. Toss out old nylock nuts that don't grip sufficiently, they will never work as needed again. You should not be able to tighten a nylock nut with your fingers, much less one will notice a difference between a new one and one that's been used a lot. When a nylock nut fails to maintain it's tension on the screw thread, it needs to be replaced.

In other words, it becomes more like a normal nut at that point and somewhat easy to un-screw. The thread deforming nut or simply replacing the nylock with a new one might be an option.

Otherwise and always now, as part of the prep of the fixture for a show, checking that the right side was sufficiently in tact it would not fail might be a better option.

A further option might be Thread Llocker compounds such as a #242 which might help the nut in not coming loose.

I have often found that the screws mounting the fixture mounted sub-yoke (#20-3154) on similar fixtures, it either becomes un-welded or un-screwed as a more design flaw than maintinence issue. Given this part is still attached, I can't see much that could be done to change the problem other than when I occasionally work on similar fixtures, me also doing the above in checking if the right side of the yoke mount is able to come loose on it's own. I would call it the Left side but what ever the case is dependant upon knob adjustment side verses bolt side. Again, should the knob become un-done that's the operator's fault.

Thans for noting something to inspect when I also service call similar fixtures. On the other hand, sorry to say but I can't see anything wrong with the design given proper inspection before use. You should be able to note when an exposed nut comes loose.
 
That's the problem with high school, the pressure to avoid liability lawsuits is huge. Some places flat out canceled their theatre programs just so that their underwriters could get some sleep at night. Anyway, with even the slightest head trauma it's worth getting checked out. I have a prominent scar on my right eyebrow because nobody bothered to send me to the hospital for stitches, could have been easily fixed.
 
It would seem that what seemed to be nylock nut in the photo was just a standard nut but with cone washer to lock it into place. While the cone washer is a good type of lock washer that adds tension the more it's tightened, short of having a locking nut it just might let the normal nut come loose if not tensioned sufficiently.

My recommendation would be either to use a side lock nut in the place of the normal nut in all similar equipment, or reverse the bolt in the yoke if possible and use a 1/4" longer one to use a nylock nut.

Sorry if my above statements about the seeming operator error was not helpful or misguided. While some of it could have been corrected by checking the nut's tension, and certainly that of the knob before use, it should not have been able to just come loose like that. That is a design flaw.

Anyway, I hope it helps.
 
krhodus said:
Today I was adjusting the heigh on an Altman Commet. I didn't realize how loose the knob on the yoke was, and so the whole light fell on top of me. The intersting part was I didn't feel the gash it left in my head. I only noticed it afterwards when talking to our TD and saw blood on my hands. By then it was really bleeding. Our SM cleaned me up while lecturing me on why did I have to do this and why didn't I feel any pain. I was forced by the TD to leave and get it looked at. That was a long fight. I believed that tech came before a little cut. He didn't. He ended up forcing me to sit down or be banished from the theater, and he went and got my stuff and watched me until I left. In the end he won, I ended up getting 4 stitches to close the wound. Luckily it was only the cornor of the light that hit my head.

Kevin


For whatever it worth.... As a former EMT--you can cut yourself or rip yourself open or break body parts and most times you will not feel anything. In war, it was not uncommon to see a guy tucking his intestines back inside himself cause he just got blown apart. Pain receptors INSIDE your body are minimal--most are in the skin surfaces--and your brain has virtually NO pain receptors in its content--that too is on the outside. But mostly its because in situations that shock or surprise or hit you suddenly (like something fallin on you or something swinging around and hitting you by surprise), Adreneline is rushing around and your pain receptors are dampened even more. Primal instinct is to react quickly--so your body flushes you full of those tastey adrenelines, so if you have to react quick or "flee"--you have the adreneline already there surging. You will probably feel the pain later...presumably by your body's instincts, when you are away from the threat that released the tastee adreneline surge in the first place.

Head wounds, even super tiny pin-prick ones, bleed a lot--reason being there are a ton more blood vessels in your scalp then most anywhere else in your body. But also, Head wounds of any kind--even a small bump or cut, should not be discounted or brushed off--tech week be damned. See, your head is basically a bowl of semi-hardened jello--sloshing and banging and ANY impact can and do have effects--some serious, and when it comes to the head--some effects may not be noticed or pronounced for hours or even days after being impacted. In head wounds--especially the bad ones, it can take time for any serious bleeding or pressure to build up inside that bowl of semi-hard jello...until it reaches a point where it can't hold any more--and then you have big problems.

If you bang, bump or cut your head or cut open deeply any bodypart--always better to be cautious for a couple of hours to see how your body reacts. Headaches, dizziness, numbness, irritability or sleepyness are bad signs after a head impact. In spite of what you may think or feel, especially in teenage years, when to comes to your health--you are NOT super invincible-indestructo-tech...I have seen plenty of folks die who were under the age of 17. Be glad you are fine...and do not feel bugged that folks did what they did when it happened--it was done in your best interest and care... If anything--If no one gave a damn when seeing me bleeding--it would be time for some new friends.

-"Dr." wolf... :)
 
In also having medical training, I agree with Dr Wolf's comments here.

Another thing about head wounds is that unless the blood is gushing, or the cut is above an eye, you will probably not see the blood or even notice the cut. After all, it is pretty hard to see your own head without a mirror. Cut hand, arm, leg etc and your instinct is to look at the area.

In addition to this, knowing that something has hit you, you expect to feel some pain and in reality cannot differentiate between the pain fro a cut as opposed to a hard blow.

The worry (in addition to a concussion) is that you could become hypovolemic from the blood loss. Even a slow trickle can cause enough blood to be lost if left for too long. Imagine becoming hypovolemic whilst up on the catwalk or operating a counterweight system. Dizziness and fainting could land you (or someone else) into a hospital bed with far worse injuries that a head laceration.

As also previously said – if injured, report it and get it checked out – no matter how insignificant it seems or how you actually feels. You may be placing yourself, your colleagues and even your theatre program at risk otherwise.
 
On a semi-related note, I had a spot operater who would loosen it up so much, that it would fall out. She did this every show. I've had a perfect safety record so far, so I got pretty pissed, besides having to run up to the catwalk to fix it. Thankfully it landed on the catwalk, and not into the audience. Not sure what I'd do if that happened.

Our sound guy suggested I reverse the polarity on the 110v line so that when I flip the spot undim channel on, she's fried. :)
 
HA, HA, HA. I have thought of doing something like that because the kid who runs our spot, now matter how many times you go over cues w/ him he never gets then right.
 
I agree with you, tech comes first and no matter what the show must go on. One time I was in our crow's nest at the old HS and was operating a spot. Well apparently somewhere along the line someone adjusted the light and did not properly tighten down the clamps. I turned to follow someone and all of a sudden everyone is looking towards the crow's nest to see who the idiot is that can't keep the spot light from falling on him. Yeah it saucked, but I was ok and so was the spot. We fixed it with duct tape, ribbon, screws, and bolts. It looked bad but did its job.
 

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