Conventional Fixtures Source 4 Sagging

[JaredU123]

Hey CB,

We recently hung some source 4's from a bar hanging down from our ceiling with some gobos in them. They fixtures have started to sag down, and the images from the gobos are moving from their correct placement. We've tightened them as tight as they can go, but have been unable to keep them from sagging. Is there anything we can do to fix this? Any help is appreciated.

Thanks!

 

[sk8rsdad]

One of 2 things come to mind:

1. nose-heavy source 4's (5 & 10 degree, zoom) have 2 tilt knobs. If yours have 2 then use both.
2. if the tilt knob get over-tightened it ruins the threads and consequently wrecks their holding power. The only fix to that is to replace the tilt knob.

 

[JaredU123]

One of 2 things come to mind:

1. nose-heavy source 4's (5 & 10 degree, zoom) have 2 tilt knobs. If yours have 2 then use both.
2. if the tilt knob get over-tightened it ruins the threads and consequently wrecks their holding power. The only fix to that is to replace the tilt knob.

Thanks for the speedy reply (and I love carl from jimmy neutron, lol)

They're all 36 degrees, and I dont believe they've been over-tightened. They are a little old though. I suppose the tilt knob could be wearing down simply from usage. Is replacing them something we should look into? How much does one normally cost?

 

[Les]

Are you sure it's the fixtures sagging and not the gobos slipping in their holders?


Sent from my iPhone using Tapatalk

 

[JaredU123]

I suppose anything is possible. If that is the case is there anything we can do to keep the gobos from slipping?

We have an event now but once it's over we're going to go look at them again and see what's up.

 

[TheaterEd]

Older Gobo holders tend to get opened up and don't hold the gobo as tight. Make sure they are shut tightly.

 

[chawalang]

Mark the pan and tilt with a China marker on the fixture. this way you can see if they have actually moved at all or if it is something with the gobo holder.

 

[derekleffew]

Are you sure it's the fixtures sagging and not the gobos slipping in their holders?

If the template was slipping DOWN in the holder in the gate of the ERS, wouldn't the image appear to be moving UP? I suppose it's possible that somehow the gobo is defying gravity and working it's way up, but doesn't seem likely.

Perhaps the OP just needs an Altman wrench or similar to crank down on the tilt-lock knob.

... Is replacing them something we should look into? How much does one normally cost?

It's more likely the carriage bolt rather than the knob, but both are inexpensive.

[HASHTAG]#12[/HASHTAG] on illustration above: ETC part# HW8144 Carriage bolt 5/16"-18, 3/4" long, http://www.productionadvantageonline.com/Products/HW5125.aspx , $0.17.
[HASHTAG]#8[/HASHTAG] on illustration above: ETC part# HW8144 Yoke knob handle 5/16"-18, http://www.productionadvantageonline.com/Products/HW8144.aspx , $1.69.

Buy enough so that you can make the units into double-clutch fixtures and you'll be all set for scrollers, I-Cues, whatevs.

 

[BillConnerFASTC]

Is the batten actually sagging or rotating? Are they roostered out at all?

 

[Kelite]

Thanks Derek, I was thinking the same when I read your post-

 

[Les]

If the template was slipping DOWN in the holder in the gate of the ERS, wouldn't the image appear to be moving UP? I suppose it's possible that somehow the gobo is defying gravity and working it's way up, but doesn't seem likely.

Perhaps the OP just needs an Altman wrench or similar to crank down on the tilt-lock knob.

Well, there is that.

I do think it could be related to the heat/cool cycles (or batten rotation). The disc/clutch system on a Source Four is pretty simple and not too prone to wear.

 

[MNicolai]

Well, there is that.

I do think it could be related to the heat/cool cycles (or batten rotation). The disc/clutch system on a Source Four is pretty simple and not too prone to wear.

Prone to wear, not so much. I have seen the brass(?) threads on the knob get cross-threaded and make it unable to keep a tight grip on the clutch disc. Usually pretty simple to tell if that's the case because when you go to tighten, you hear a kind of screechy sound.

 

[Les]

Prone to wear, not so much. I have seen the brass(?) threads on the knob get cross-threaded and make it unable to keep a tight grip on the clutch disc. Usually pretty simple to tell if that's the case because when you go to tighten, you hear a kind of screechy sound.

I know that noise. It is pretty obvious when there's a problem in the clutch itself - it might make some noise, or the knob will continue spinning, failing to ever tighten completely.

Make sure you tighten the hex bolts where the yoke actually attaches to the body, not just the t-handle.

 

[KeepOnTruckin]

Prone to wear, not so much. I have seen the brass(?) threads on the knob get cross-threaded and make it unable to keep a tight grip on the clutch disc. Usually pretty simple to tell if that's the case because when you go to tighten, you hear a kind of screechy sound.

Nothing worse then focusing a S4 and hearing that screech...you can crank that knob as hard as you want and the light is not going to lock down.