Wiring a Uni with a New Switch

[Anthony Visconti]

I recently picked up a complete '51 Uni in need of just a minor restore. It came with the OEM dust door, pecker switch with box and "Delta" plate, home made but really nice fence and mobile base, miter gauge and a Delta 1hp single phase bullet motor. All for $250.

I need the door, miter gauge and possibly the switch for my '66 Uni that I 90% restored in '04. My plan is to attempt to sell the remaining as a ready to go running machine and capable of 110/115v. If it doesn't sell a a whole I'll piece it out.

Since I'm yanking the switch I picked up another from Rockler on sale recently. See here.

Rewiring the motor to 115 it will draw 11.8 amps.

Any reason this switch and motor won't play nice together? I asked on Rockler's site and they say it will work, but since I have additional Q's I thought I'd double check here.

The switch comes with 14 gauge cord. When I rewire the motor I assume I stick with the same gauge, correct? Is it okay to plug the motors cord into the switch or is there a reason that it needs to be hardwired directly?

Lastly, I was told elsewhere that the motor needs to be grounded. There are no ground screws in the motors jbox. How would I ground it to the switch?

[stan shields]

Anthony-That switch should be OK, although the in-rush current will be significantly higher than 15amps, may shorten the life of the switch. Hardwiring is generally better if you can do it, not sure what's inside the switch box though. If you use the plug it will be fine, it's just one more connection to potentially cause problems, it's a lot of current to draw through the male/female connectors and you have sawdust to consider. Feel free to run a seperate conductor from the motor casing to the ground connection inside the switch box if the motor case is not already connected to the ground terminal where you connect your cord, check this with an ohm meter. As far as wire size goes, bigger is better, shorter is better.

[Bill Orbine]

You need to think about another thing.... That switch won't work if you have LVC (Low Voltage Controls) or motor relay controls on the machine. Not sure if your '66 Unisaw has it or not. You probably don't have it on the older machine.

[Anthony Visconti]

You need to think about another thing.... That switch won't work if you have LVC (Low Voltage Controls) or motor relay controls on the machine. Not sure if your '66 Unisaw has it or not. You probably don't have it on the older machine.

Which switch are you referring to? The older switch going on my '66 which has a newer Balder 3hp/single phase in it? If not I'd still like to yank it and either keep it as a spare for my HD Shaper or sell it separately.

Anthony-That switch should be OK, although the in-rush current will be significantly higher than 15amps, may shorten the life of the switch. Hardwiring is generally better if you can do it, not sure what's inside the switch box though. If you use the plug it will be fine, it's just one more connection to potentially cause problems, it's a lot of current to draw through the male/female connectors and you have sawdust to consider. Feel free to run a seperate conductor from the motor casing to the ground connection inside the switch box if the motor case is not already connected to the ground terminal where you connect your cord, check this with an ohm meter. As far as wire size goes, bigger is better, shorter is better.

Stan, In that case I'd rather snip off the supplied plug and hardwire it, yet use the supplied cord. I opened up the switch and can connect my ground to the other grounds which are on the plate that the two buttons are also mounted to if that makes sense. I can simply drill a separate in the box to have the ground run through. I can't use a larger gauge with this switch as there'd be no room for it going in.

[Dave Zellers]

Those slap switches can be really handy on table saws and router tables if you position them so a bump of the knee (or just above) kills the power.

Very handy when you are cutting to the middle of a piece and need to hold it steady while the blade / bit winds down. Even with regular operations it's great to shut down with just a gentle bump from your leg while your hands are doing other things. Also for a piece that starts binding on the TS- hold it steady and bump the motor off.

[Bill Dufour]

Ground wire is easy, just run it under the screw head of a screw that holds the j box onto the motor. If the j box is welded on crimp a ring terminal on the green wire. then carefully hook it so the screw that holds the j box cover on sandwiches then ring terminal under the cover. Just make sure the wire contacts bare metal not painted.
Good idea to make sure the machine is grounded not just the motor. The motor may be on rubber mounts and standard vee belts do not conduct electricity. Grounding the metal body of the machine is good safety practice and it may help reduce static charges if that is a problem.
Bill D

[stan shields]

Sounds like a good grounding scheme. I am surprised that the motor case is not already grounded tho...