Project: motorized rising microphone HELP!

Discussion in 'The Projects Forum' started by jreb, May 24, 2012.

  1. jreb

    Thread Starter New Member

    May 24, 2012
    Goal: to have a retractable microphone descend from the attic with limit switch using easy to get parts for future repair by anyone who takes over when I’m gone. I would like to keep this project under $100 because if at that price I could buy an electric hoist and where is the fun in that?

    Plus: variable-speed / everything running on A/C power

    Situation: attic in Texas can reach 150° degrees which is where the motorized spool is going. I got the spool with cable ready to go. It lowers and rises just fine.
    I will be standing 60 feet away plus ceiling height of around 15' which is where I want to have the switch. I would like to add a limit switch so it turns off going up but still go down.

    Problem: I was thinking of using a reversible drill but I can’t figure out how to wire in the limit switch. Any way I do it creates an open circuit and drill wont reverse. Also I think I need to replace the switch because I am assuming if I run 70' of cable to and from the drill the circuit board in the switch will burn out due to distance.

    Alternate: I was thinking taking apart an rc car and taking advantage of the wireless motor but I don’t think the circuit board and motor can take the heat of the attic.

    harborfreight 3-8-eighth-inch-variable-speed-reversible-drill part # 3670\
  2. wayneh


    Sep 9, 2010
    Do you need it to go auto-off when going down also? For going up, I think you could put a disc or ball on the cord and pull the cord thru a ring holding a limit switch. When the disc hits the switch, it goes off. You'd need something else going down.

    [edit] Oh, sorry, I guess you were asking about the circuit.

    [edit 2] Got an old shredder laying around? I just tore one apart that had a broken gearbox. It'd be perfect for this operation. You could use the reverse switch to go down. It only stays on while pressed. Going up, you'd just need a mechanism to allow the paper-sensing beam to open up, stopping the motor. The reverse (down, in your case) is still active even if the beam is complete.
    Last edited: May 24, 2012
  3. jreb

    Thread Starter New Member

    May 24, 2012
    thank you hope this hold up with the heat.