Rosco Vortex 360 gobo rotators

propmonkey

Well-Known Member
Joined
Jul 22, 2004
Location
Milwaukee, WI
we recent purchased 2 of them. we are currently doing A Midsummer's Night Dream and i have them in a ETC S4 15/30 750w zoom. i have 2 rosco realistic gobos in them in rotating in opposite directions. im having trouble keeping them at the speed i want. i want them as slow as possible so it looks like trees in the wind. but when i set them on the lowest speed possible. ill set them and fly up the pipe and then i turn the rotators off on back on( i have them in a dimmer patched as a nondim) they stopped. and i cantfirgure out why they are doing this.
 

koncept

Active Member
Joined
Mar 6, 2005
Location
.
my only guess is when it is getting flown up the speed falls lower. (unless when you bring it back down, it works)

what happens if you put them on a dimmer, but not patched as a nondim and just keep it at 100
 

tadawson

Member
Joined
Apr 4, 2005
Location
Lewisville, Texas USA
I'm bettinng friction. It takes a lot more force to get something moving than it takes to keep it moving. So, my bet is that you have them set so slow that they don't have enough "grunt" to get started once stopped.

- Tim
 

propmonkey

Well-Known Member
Joined
Jul 22, 2004
Location
Milwaukee, WI
ok, thanks. ill try to get them as slow as possbile with out stopping.

also will it hurt them say if i fade them up like over 2-3 seconds?
 

bdesmond

Active Member
Joined
Mar 8, 2004
Location
Chicago, IL USA
Generally speaking motors and dimmers don't really work well together. This is something you'd have to ask Rosco about, but I'd plan on putitng the power for the unit on a switched circuit. You can fade the intensity of the light up via the dimmer, of course. I'm not sure why yyou'd wnat to fade the rotator anyway. If you want to chang eht espeed over a few seconds, that's more a programming the DMX levels into cues issue.
 

BNBSound

Active Member
Joined
Mar 17, 2005
Location
Alexander, NY
It's all a matter of thresholds. A motor draws more current when starting than running. So if you start with the motor off and sneak up the speed control till it turns on, you can then turn it back down below that initial threshold. Just inch up the speed till they run reliably every time you hit the non-dim, because you definately don't want to dim a motor, there's other circuitry for that.
 

Eboy87

Well-Known Member
Joined
May 3, 2004
Location
Chicago, IL
I was looking throught these old posts and found this. We have some Rosco vortex gobo rotaters, not sure what model number it is, but, we've always run the motor with two channels on the dimmers (one forward, one backward). We've also used them to speed up and slow down the speed they rotate. After reading this, it seems like this is a really bad idea, but we've had no problems, and, from what I understand, this has been done for years. In other words, should we not do this anymore?
 

propmonkey

Well-Known Member
Joined
Jul 22, 2004
Location
Milwaukee, WI
ares arent dmx controlled. we got the "cheap ones". i still could never get them to go that slow as i wanted but it worked out. ill see if i can post a pic.