Shopsmith Forums

dusty wrote:I do not not believe that there is any danger involved with switching only the "hot" wire. Do not switch "only the neutral (white) wire".

In the case of later model Mark Vs, I understand they came out of the factory with only the hot wire being switched. My Mark Vs are both wired with only the hot wire being switched and have been that way for a long time (years).

I concur with Dusty. It is a safe temporary fix until you can get a new switch.

There be no reason to hurry with a 'permanent' fix!;)

Make sure to secure and insulate the 'splice'. If each terminal is still on both white wires, a short 1/4" conductive strip will connect them.


P.S. Beeg's suggestion is also 'cool'!

jimjulien wrote:Does anyone know if you can get a switch at Radio Shack to replace the switch on the 500 SS. Also can you solder the leads to the switch?

Jim

Don't know about Radio Shack, but I have purchased them from a San Diego store called Willy's Electronics. They have a web presence also. If you let people know where you are located, you might get some other suggestions closer to your home.

Yes I should add that. I am in Palm Springs no electronics stores out here other than Radio Shack. I went to Radio Shack and their switches did not have the amp rating of this switch.

I made a temporary fix by soldering a wire on what was left of the tab and then soldered a spade lug on the other end. Slipped the wire over the spad lug and then heat shrinked it.

Thanks
Jim

jimjulien wrote:Yes I should add that. I am in Palm Springs no electronics stores out here other than Radio Shack. I went to Radio Shack and their switches did not have the amp rating of this switch.

I made a temporary fix by soldering a wire on what was left of the tab and then soldered a spade lug on the other end. Slipped the wire over the spad lug and then heat shrinked it.

Thanks
Jim

BEEG to the rescue!:D

I think I got the last replacement switch I used at Menards. I believe the maker is Gardner-Bender. I think it's just a double pole, single throw switch.(I might not be remembering the "single/double" thing correctly, but It looks like the SS switch & mounts easily. Just make sure you get one with load capacity comparable to what you have. It's a cheap easy replacement

trainguytom wrote:I think I got the last replacement switch I used at Menards. I believe the maker is Gardner-Bender. I think it's just a double pole, single throw switch.(I might not be remembering the "single/double" thing correctly, but It looks like the SS switch & mounts easily. Just make sure you get one with load capacity comparable to what you have. It's a cheap easy replacement

What really matters is the hp rating if controlling induction motors.

If you got switch rated 1 1/2 hp at 120v yer on the ball. It probably is also rated 20A at 115v. A 10A or 15A rated switch usually will not last as long(the contact area is smaller). GSW-14 is a DPST, but has screw terminals.

I have been buying a 20 AMP HD motor rated switch #7300001 ($5.41 now) from http://www.delcity.net/store/Heavy!duty ... 68.a_1.t_1 for many years without any failures.

billmayo wrote:I have been buying a 20 AMP HD motor rated switch #7300002 ($6.00 now) from http://www.delcity.net/store/Heavy!duty-Motor!rated-Toggle-Switches/p_789066.h_789069.a_1.t_1 for many years without any failures.

7300001 will do and is slightly cheaper($5.41).

Bill uses the dpdt switch for a direction reversing switch and apparently stocks the one for either use.

My logic is to relate the component (a switch in this case) to amps, since amps are related to hp. Hp is a function of amps.

HP = V x I x Eff
746

Where: HP = horsepower
V = voltage
I = curent (amps)
Eff. = efficiency

So, by my my logic, you get a switch that is rated for at least the amps the motor draws (plus a little) & you're fine. As I remember, when I tested a
1 1/8hp SS motor it pulled about 9-10 amps (not exact, from my memory which, if you ask my wife, is not that good)
Working backwards from the known HP, amps & voltage, I came up with around 90% efficiency, which I also plug in to test HP on older 3/4hp SS motors after I put in new bearings. Interestingly enough, using that coefficient for friction, most 3/4HP motors run at around 1-1 1/8HP.
I think Bill Mayo can verify this as well. We've talked about the under rating of the older motors.
Sorry, didn't mean to get off on a tangent.

trainguytom wrote:My logic is to relate the component (a switch in this case) to amps, since amps are related to hp. Hp is a function of amps.

HP = V x I x Eff
746

Where: HP = horsepower
V = voltage
I = curent (amps)
Eff. = efficiency

So, by my my logic, you get a switch that is rated for at least the amps the motor draws (plus a little) & you're fine. As I remember, when I tested a
1 1/8hp SS motor it pulled about 9-10 amps (not exact, from my memory which, if you ask my wife, is not that good)
Working backwards from the known HP, amps & voltage, I came up with around 90% efficiency, which I also plug in to test HP on older 3/4hp SS motors after I put in new bearings. Interestingly enough, using that coefficient for friction, most 3/4HP motors run at around 1-1 1/8HP.
I think Bill Mayo can verify this as well. We've talked about the under rating of the older motors.
Sorry, didn't mean to get off on a tangent.

Your logic does not include the inductance of the motor. With a collapse of a magnetic field is the dissipation of the energy stored in that field. This results in an arc across the suddenly opened contact points. Those switch contact points must be capable of absorbing the heat generated by the arc. There is also the starting surge current which is considerably more than the normal running current.

If we were switching a purely resistive load, yer logic would be correct.