Mini mac profile problem

[Wacdeejay]

Hey Everyone,

New to the forum, this looks like a great place for a lot of information!

 

I'm having an issue with one of my mini macs profiles. The gobo wheel is stopping right between the gobos. You can see two "half" gobos with the frame basically in between them. I have tried everything I know to try, I've even swapped the color wheel and gobo motors just to make sure it wasn't a motor issue. I don't know if the the motors not receiving the proper amount of "steps" from the mobo or what.

 

 

Any help would be greatly appreciated!

[DrV]

Hey Everyone,

New to the forum, this looks like a great place for a lot of information!

 

I'm having an issue with one of my mini macs profiles. The gobo wheel is stopping right between the gobos. You can see two "half" gobos with the frame basically in between them. I have tried everything I know to try, I've even swapped the color wheel and gobo motors just to make sure it wasn't a motor issue. I don't know if the the motors not receiving the proper amount of "steps" from the mobo or what.

 

 

Any help would be greatly appreciated!

 

Hi,

 

This is very probably either 1) a wiring fault or 2) a blown driver or it's 2) caused by 1). The wires for the gobo motor run across the front of the head near to the fixing screw and can get trapped by it. If a wire gets broken you may see the motor juddering when it's trying to reset. If a wire gets shorted down to the chassis it will blow the driver chip. Check the wiring first for shorts and opens and then change the driver chip. It's the end one of the row but without a unit in front of me I can't describe which end! There should be a diagram inside the cover. These units do not have a position sensor, they just wind the wheel against the endstop to calibrate their position.

 

A test you can do to prove that there's a drive problem (either 1) or 2)) is to put the wheel half way by hand and then cause a reset. Once the wheel starts moving you'll be able to coax it into going in either direction with a little push. If the drive is OK then it will resist going the wrong way but will be happy to go the right way until it reaches the stop.

 

Good luck

Dave

[Wacdeejay]

Thanks so much for the response,

The wheel has no problem resetting, and it actually moves all the way through the wheel while doing a test, it just stops between the gobos. It starts the test with the "open" gobo where it should, and then moves to a spot in between two gobos, does it's rotating test, moves to the next spot between gobos, does it's rotating test etc... it will go all the way through like that.

 

I don't know if that changes anything with the diagnosis, but I'll check in to what you already mentioned, and see if I find anything.

 

 

Thanks again

[DrV]

Thanks so much for the response,

The wheel has no problem resetting, and it actually moves all the way through the wheel while doing a test, it just stops between the gobos. It starts the test with the "open" gobo where it should, and then moves to a spot in between two gobos, does it's rotating test, moves to the next spot between gobos, does it's rotating test etc... it will go all the way through like that.

 

I don't know if that changes anything with the diagnosis, but I'll check in to what you already mentioned, and see if I find anything.

 

 

Thanks again

 

Check that the end stop hasn't fallen off then - IIRC it's a long bolt sticking out of the hub radially. If it's bent or has fallen out then the unit will reset to the wrong point. I might be thinking of another fixture but the stop may be on the opposite end of the motor to the gobo wheel????

 

Dave

[Wacdeejay]

The stop is still in place, it resets to the right spot. the first gobo in test is in the correct position, it gets off when it moves from there.

 

So far have not found any bad connections either.

 

Thanks!

[Wacdeejay]

New info,

 

I ran through the test with the cover off and manually adjusted the wheel to the correct positioning and when it would move it would still "land" incorrectly, so I would readjust and it would still move again and land off.

 

really at loss here. If I lived in a town (or even close to) that had a place to get it repaired I would just take it, but shipping it is risky besides expensive.

[JayeJsav]

Hiya,

 

When you did the adjustment to the wheel position on the shaft, did you unscrew the two "grub" screws on the wheel?

 

I have had this happen on a colour wheel before, and the cause was that when it was adjusted (before it came to me), the wheel was replaced, and set between steps of the motor, so when it did it's "bash bash bash reset done" motions, it would spring out too far and thus effectively lose steps after the reset.

 

To make it right, I loosened off one grub screw to being loose enough for removal, and loosened the other one, and then re-tightened by one turn. Watch the reset to see which one is still accessible afterwards. Loosen the one which you can get to, (might need both covers off, fan disconnected, lamp out), and move the wheel into the right position. When you turn the wheel, make sure it moves freely and doesn't turn the motor spindle (so you should NOT feel any resistance to your movement of it). That will keep the motor at it's right step, and put the wheel back into the right position.

 

Might take a couple of attempts to do, and a couple of resets. Don't forget though, don't do it with the lamp on!

 

HTH

 

Jaye :)