Introduction: Portable Power Switch
I recently purchased a small bench wood lathe. The power switch that comes installed is on the right side. I hold tools in my right hand. When I need to shut the power off it is quicker to use my left. I didn't want to mount anything permanently so I went about designing a clamp on bracket with attached switch.
Step 1: Design
My plan was to build a clamp out of scraps of wood that a standard utility box could be mounted on that an emergency stop switch would fit into.
Step 2: Construction
The vertical member is 3/4" plywood 7 3/4 long x 2 1/4" wide. The block at the bottom is 2x2" x2 1/4". The block is for extra support for the cross bar.
The cross bar is 2x2" x 10" long.
The clamping piece that sits on top of the desk is plywood 1 1/2 " thick (2 3/4" pieces glued together) 6 1/2 " long x 2" wide.
All wood mounting is glued and screwed.
The threaded rod is 5/16"-13 tpi. x 4 1/2" long. I used T nuts in the cross bar but they have a tendency to pull out. Next time I will epoxy them in or use threaded inserts.
I made the knobs and pressure plates myself from wild plum and installed threaded T nuts which I epoxied in place.
Epoxy | Definition of Epoxy by Merriam-Webster
verb. epoxied or epoxyed; epoxying. Definition of epoxy (Entry 2 of 3) transitive verb. : to glue, fill, or coat with epoxy resin.
Step 3: Electrical Connection
I bought a 10' extension cord from Harbor Freight. I cut the wire 3 feet from the socket end. I will plug my machine into this end.
That leaves 7 ' for the other piece to reach my power source.
I stripped all the ends, twisted the two green ground wires together and tightened a wire nut to hold them together.
Next, all the ends got a crimp insulated female disconnect. The terminal side of the switch shows which terminals are the input and which are output. Follow this closely, it won't work otherwise.
It doesn't look like it all fits in the utility box but if you are careful and bend the wires around to make room for everything, it will fit.
I made a loose square knot in the connection to the lathe just to make sure it doesn't pull out by accident.
Step 4: Final Mounting
As soon as I clamped it to the table I noticed it slowly slipping off. I cut a piece of sand paper and glued it to the underside of the top clamping piece. That did the trick, no more slippage! Finished! I haven't decided to paint it yet. So far I like it raw.
Step 5: Other Uses
I wanted to see how it would work with other machines. It does clamp on the other tables and works to switch them on and off but I am most happy with the use with the lathe.