Electronics

[blackhawk89]

I`m doing a show in which I need a clock to change speed during the play.

The minute hand on the clock essentially needs to start off at a 'ticking speed' and at points speed up to a spinning (clockwise) style and then have the ability to return to the original speed.

It would probably need to change speeds about 10 times. Not to mention the show is being performed around 10 times.

Would be great to know how others would achieve this.

Cheers

H x

[Glyn Edwards]

I`m doing a show in which I need a clock to change speed during the play.

 

The last time I did this I butchered a cheap (Maplins disco tat) moving light, and reworked a continuously rotating gobo wheel to have a "pointer" attached.

This was then built into a clock face et voila. At one value of DMX you have a clockhand that rotates at "Realtime" and then for a different value either faster or slower depending on your requirements.

 

Glyn

[Brian]

Meccano + Stepper Motor + DMX to Stepper Interface Board =

 

[blackhawk89]

I`m doing a show in which I need a clock to change speed during the play.

 

The last time I did this I butchered a cheap (Maplins disco tat) moving light, and reworked a continuously rotating gobo wheel to have a "pointer" attached.

This was then built into a clock face et voila. At one value of DMX you have a clockhand that rotates at "Realtime" and then for a different value either faster or slower depending on your requirements.

 

Glyn

 

Cheers Glyn.

 

I shall have a look into that. Sounds good though

 

I`m really up for any suggestion as the cheaper and quicker option is what I`m after...which it always is in theatre haha.

 

Hayle

[themadhippy]

Didn't there used to be those sychronise clock things,took its timing from the mains frequency,change the mains frequency, change the speed of time

[daifuse]

I`m doing a show in which I need a clock to change speed during the play.

The minute hand on the clock essentially needs to start off at a 'ticking speed' and at points speed up to a spinning (clockwise) style and then have the ability to return to the original speed.

It would probably need to change speeds about 10 times. Not to mention the show is being performed around 10 times.

Would be great to know how others would achieve this.

Cheers

H x

 

I built a clock of this type for Cinderella two years ago. The clock (suspended from the flys) had to run at a normal speed (approx.) and then speed up to indicate a rapid passage of time (3 hrs.) to just before midnight. A butchered brass alarm clock movement was driven by a 12v DC motor and gearing (from CPC) and the speed was controlled by an emitter follower transistor circuit fed by the 0-10v decoded DMX level from a dedicated demux on the clock. The biggest problem was making the clock hands for a 1metre diameter clock face counter-balanced and stopping them at 11.55! However, it ran for 52 performances and only 1 hiccup and that was op error!

 

Dave

[dbuckley]

If anyone wants to build Brian's meccano clock I have a bill of materials of meccano part numbers somewhere, which should duplicate what Brian did.

 

When I needed a controlled clock I used an off-the-shelf Gents Pul-Syn-Etic clock, which I drove with a DMX relay. But it wont go fast enopugh to spin ;)

[paulears]

The usual no budget response is a mechanical one - work the hands from behind with a person winding like mad on cue.

 

You've got some sensible solutions - find an old mover and the meccano DMX one. If these are not to suit - then it's something in between, at whatever level your construction skills are. With problems like this one, it's often difficult to blend the solution from other people's skills.

 

Brian's solution involves mechanics and electronic construction. Maybe this is difficult for you, so won't be high on your list. If you have a bit of budget - then maybe you could just buy a duplicate servo - and then you won't have to wreck a mover - just disconnect the internal one and extend the cabling. This is probably what I'd do for simplicity, but you could just as easily just take a suitable clock, and extend the setting knob through a flat - or any way in between!