Switch Replacment on Mark V Greenie

[DNez2001]

I recently purchased an older Mark V Greenie, and replaced the 3/4 HP AO Smith motor with a 1 1/8 HP motor I took out of a 1984 Mark V when I upgraded my original to a Power Pro motor controller. However now I need to replace the switch in the Greenie, as it has burnt out and will not start my 1 1/8 HP motor (motor does run when I wire it directly). Any suggestions? Is the replacement a simple SPST switch? There doesn't seem to be much clearance between the switch and the quill.

[garys]

My Mark V uses a DPDT switch for the 1 1/8 hp motor. It switches both the hot and the neutral side of the wiring.

[wa2crk]

Why don't you use the switch that was in the '84. A SPST switch will suffice but sometimes Shopsmith used a DPST swiitch to break both sides of the power. Use a 20 amp rated switch because of the startup current and rated at 2 horsepower. Should be able to be obtained at Lowes or a well stocked hardware store.
Bill V

[DNez2001]

My Mark V uses a DPDT switch for the 1 1/8 hp motor. It switches both the hot and the neutral side of the wiring.

Why don't you use the switch that was in the '84. A SPST switch will suffice but sometimes Shopsmith used a DPST swiitch to break both sides of the power. Use a 20 amp rated switch because of the startup current and rated at 2 horsepower. Should be able to be obtained at Lowes or a well stocked hardware store.
Bill V

I can't use the switch in the '84, as it is a "square hole" for the plastic body switch, vs a 0.5" round hole in the Greenie. I thought it was very redundant to break both sides of the power, but that is easy enough to do. Anybody run into interference with the switch and the quill?

[jsburger]

My Mark V uses a DPDT switch for the 1 1/8 hp motor. It switches both the hot and the neutral side of the wiring.

No the SS switches that are DP are DPST. ON OFF not ON ON.

[DLB]

I can't use the switch in the '84, as it is a "square hole" for the plastic body switch, vs a 0.5" round hole in the Greenie. I thought it was very redundant to break both sides of the power, but that is easy enough to do. Anybody run into interference with the switch and the quill?

My PowerPro DIY kit came with both types of power switch. If you used the rocker, check your leftovers for a new toggle. If you have it that one is perfect.

Something not matching up here. The '84 would normally have a "B" headstock that uses the toggle. IIRC the "C" headstock with the rocker switch was somewhat later. Early 90's IIRC

I've read somewhere that switching both power and neutral extends the life of the switch by effectively increasing the contact gap size, reducing arcing across the contacts when shutting off. But it didn't include any actual scientific evidence. And it wasn't explicitly talking 'motor rated' switches, which we should be using in this application. Shopsmith has wired headstocks both ways, but most I've personally seen were switched neutral. But now that I think about it the last one I replaced the switch in was not.

I've seen interference with the quill and with other internal moving parts. It's important to route the wires carefully to prevent chaffing. And to ground the chassis of your Greenie if it is an early one and it hasn't had the ground added.

Edit - Not a 'buy this one' endorsement but if you look at this ad he has a lot of details about the switch: https://www.ebay.com/itm/274072279401?h ... Sw9uFW9c-1 Especially see the second pic. This one is 2HP motor rated, which is excellent. I don't recall the ratings on the one Shopsmith currently sells.

- David

[Hobbyman2]

Thats is a good price for a motor control switch , I paid over 75.00 for a switch for my ryobi planer / jointer but it had the plastic lock out safety tab .

[garys]

You are correct. Mine is DPST, not DPDT like I was thinking.
Mine are similar to this.
https://www.acehardware.com/departments ... es/3468790