Like many of you Home Shop Machinists, shop space is at a premium. My shop is located in my garage where I also store a few motorcycles and my  vintage sports car.
A big fear I have is one day turning on the lathe accidentally with the chuck key still in the chuck, and flinging it across the shop into the windshield of the Porsche!
I needed to create some type of interlock so I could not start the lathe unless the chuck key was removed and stored somewhere.
A simple solution was a piece of aluminum tubing with a lever switch tied into the lathe’s electronics.
A piece of tubing was turned to the proper dimensions and a slot was cut to attach a small “lever switch”
$3.50 from Radio Shack   http://www.radioshack.com/spdt-switch-without-roller/2750016.html#q=Lever%2Bswitch&simplesearch=Go&start=7
CAUTION!!! Use a properly rated switch to interrupt  your circuit. This 5A switch is not rated high enough to interrupt the AC  line voltage to most lathe motors. I’m using a DC controller on this lathe and interrupting a low voltage area of the circuit. Be sure you are using approve wiring and electrical shock shielding standards. If you do not understand these things, please hire a qualified electrician. Improper installation could kill you!
 Using JB Weld, the switch was attached to the aluminum tubing
A couple holes were drilled and countersunk to attach to the lathe
Two holes were drilled and tapped in the lathe
A wire to interrupt the circuit (see warning above) and a bit of heat shrink tubing finishes the deal.
Now, no chance of a broken windshield!
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