OK...I need some help with a motor for an old bench grinder. It's a real old Snap On 1/2 HP 7" bench grinder which would not start on its own.
If I spinned the wheel/armature, it would start and run fine. A little background. Many years ago, when I opened up on a monday AM...I heard the grinder spinning. Either someone left it on or the toggle switch(which was on the way out) snapped to the on position. In any case...It had been running for many, many hours and had overheated pretty bad. Windings weren't fried, but the paint on the outside of the motor frame was toasted a bit.
After that...it would never start on its own without the spinning. So I changed capacitor to no avail. Long story short, I just finished disassembling it and found that one of the the wires to the centrifugal start switch had de-soldered itself from the switch.
I'm guessing from the overheating from being left on.
So I resoldered it and put it back together. and it worked fine....Kind of fine. I noticed if I turned the wheel by hand backwards...I can hear the wire rubbing against the switch.
OK...so my question is this. Is there any trick to keeping this wire away from the centrifugal switch? I hate to get it all back together and that wire to snag in a year or so. Hell...its taken me 15 years to finally overhaul the damned thing. I want it to be done right once and for all.
If you look at that wire in the picture...you can see where a little length has been crimped onto the bare copper wire which goes to the switch. I had coated that and the area leading to the crimp with liquid wire coating and it looks like its rubbed off in just the few minutes of testing before I get it all back together....so I think thats where its hitting the switch as it spins.
My plans were to cut that crimp...slide a little piece of heat shrink...solder and then heat the heat shrink. At least that way that big crimp clamp won't be hanging off the side of the wire and it will be less likely to snag.
Anyway...I'm no expert on electric motors so I was hoping for some input here...advice ?
If I spinned the wheel/armature, it would start and run fine. A little background. Many years ago, when I opened up on a monday AM...I heard the grinder spinning. Either someone left it on or the toggle switch(which was on the way out) snapped to the on position. In any case...It had been running for many, many hours and had overheated pretty bad. Windings weren't fried, but the paint on the outside of the motor frame was toasted a bit.
After that...it would never start on its own without the spinning. So I changed capacitor to no avail. Long story short, I just finished disassembling it and found that one of the the wires to the centrifugal start switch had de-soldered itself from the switch.
I'm guessing from the overheating from being left on.
So I resoldered it and put it back together. and it worked fine....Kind of fine. I noticed if I turned the wheel by hand backwards...I can hear the wire rubbing against the switch.
OK...so my question is this. Is there any trick to keeping this wire away from the centrifugal switch? I hate to get it all back together and that wire to snag in a year or so. Hell...its taken me 15 years to finally overhaul the damned thing. I want it to be done right once and for all.
If you look at that wire in the picture...you can see where a little length has been crimped onto the bare copper wire which goes to the switch. I had coated that and the area leading to the crimp with liquid wire coating and it looks like its rubbed off in just the few minutes of testing before I get it all back together....so I think thats where its hitting the switch as it spins.
My plans were to cut that crimp...slide a little piece of heat shrink...solder and then heat the heat shrink. At least that way that big crimp clamp won't be hanging off the side of the wire and it will be less likely to snag.
Anyway...I'm no expert on electric motors so I was hoping for some input here...advice ?
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