Leave the minute and second hands on the clock.
With a 12:1 clock, 1 hour would be 12 hours. 5 minutes of real time (300 seconds) would be 1 hour so 1 minute of real time would be 12 minutes of fast time, therefore 5 seconds of real time would be 1 minute of fast time. On the new face make every 5 minutes an hour and every 5 seconds 1 minute.
My head hurts, somebody check my work!!!
Seems like I did use a digital clock once, but can't recall what I did, don't think I used anything but hours.
Andre...just don't use it for switching, phase in/out of real time/fast time. I do it all the time 
