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Edge sander woes...
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Author:  Clay S. [ Fri Aug 02, 2019 8:05 pm ]
Post subject:  Re: Edge sander woes...

meddlingfool wrote:
Eek! Fingers crossed that I can gently fondle the centrifugal switch into being nice again...


Hey Ed,
Where is your sense of adventure! laughing6-hehe

The contact plate and centrifugal switch is only about $11 to replace on the Grizzly motor and I would almost bet yours would be the same.

Author:  Jim Watts [ Fri Aug 02, 2019 9:35 pm ]
Post subject:  Re: Edge sander woes...

Ed, you do want to drain the capacitor before touching it. They can hold energy for a while.
Good luck.

Author:  meddlingfool [ Fri Aug 02, 2019 11:10 pm ]
Post subject:  Re: Edge sander woes...

Right! Drain the flux capacitor before attempting the gravitron switch!

Author:  doncaparker [ Sat Aug 03, 2019 10:02 am ]
Post subject:  Re: Edge sander woes...

It won’t be 1.21 gigawatts, but it could be enough juice to make you regret not draining.

Author:  Ken Lewis [ Sat Aug 03, 2019 10:26 am ]
Post subject:  Re: Edge sander woes...

I haven't read all of the earlier responses. but, have you checked the switch, I've had several of those go kaputz on me over the years. Done that? then, carry on:)

Author:  James Orr [ Sat Aug 03, 2019 11:38 pm ]
Post subject:  Re: Edge sander woes...

I'd look for a video on draining capacitors safely, then replace the start capacitor. If the capacitor isn't bulging, it probably isn't the issue, but at least it's an inexpensive test.

If not, it's your motor. When the motor in my bandsaw went bad, it gave an electrical hum but wouldn't turn. I found a replacement Leeson farm duty on Amazon for next to nothing compared to retail.

Author:  meddlingfool [ Sun Aug 04, 2019 12:14 am ]
Post subject:  Re: Edge sander woes...

Hmm...

I'll start with the capacitor, then the centrifugal switch...

Draining the capacitor seems to happen naturally by letting it sit, or simply arcing it by touching both poles simultaneously with an insulated handheld object. I hope I don't need to replace the motor...

Author:  Woodie G [ Sun Aug 04, 2019 6:56 am ]
Post subject:  Re: Edge sander woes...

The charge on the capacitor can be measured with a multimeter, a tool which is likely to be in most shops doing any electrical repair work, or should be. Compact auto-ranging multimeters can be found for under $25, and good, basic select-range digital meters with most necessary functions for under $10.

To check for the state of the capacitor's charge, set the meter to the highest DC voltage range (or auto-range on auto-ranging meters) and attach the test leads to the + and - leads of the capacitor. Measured voltage should be 10 volts or less; anything higher and the capacitor needs to be discharged.

To safely discharge a capacitor, use a 2 watt or larger 1K to 10K range resistor and a set of insulated test leads across the terminals of the capacitor, then recheck voltage. Use a search engine and look for 'Discharging Capacitor Amplifier' for video and test articles on making and using a bleed resistor - we use Duck Duck Go, which is an ethically operated search engine that does not seek to skew search results, track our queries, or sell that data.

Author:  meddlingfool [ Sun Aug 04, 2019 4:50 pm ]
Post subject:  Re: Edge sander woes...

I think a multi meter is on the list for sure, especially since the elements on the range top have all stopped working. I don’t mind cooking outside on the bbq but I sense the lady would prefer it were fixed before winter...:)

Author:  Clay S. [ Sun Aug 04, 2019 10:18 pm ]
Post subject:  Re: Edge sander woes...

meddlingfool wrote:
I think a multi meter is on the list for sure, especially since the elements on the range top have all stopped working. I don’t mind cooking outside on the bbq but I sense the lady would prefer it were fixed before winter...:)



It's funny how wives don't feel a hot plate, an electric frying pan, and a crock pot is an adequate replacement for a range top. They treat them as alternative facts. :lol:
The last time I worked on a range I "fixed it" to the point buying a new one was cheaper than continuing to fix the old one (I cracked the smooth top).

Author:  meddlingfool [ Mon Aug 05, 2019 4:13 am ]
Post subject:  Re: Edge sander woes...

Again I hmmm...

Really hoping some cheap Lowe’s components and a multimeter will get things sorted. After a few days trout fishing of course...

Author:  Clay S. [ Mon Aug 05, 2019 8:54 am ]
Post subject:  Re: Edge sander woes...

Sounds like you have your priorities straight. bliss

Author:  meddlingfool [ Mon Aug 12, 2019 1:43 pm ]
Post subject:  Re: Edge sander woes...

Right, so I got a multimeter and today tried to test the capacitor. It looks good, no leaks or bulges or anything visible.

I set the meter to 2000 ohms. Online instructions say that the reading should steadily have gone up to max reading, but instead it went through a bunch of random numbers then went to zero. Didn’t seem to matter which pole I put on red or black...

Any thoughts?


Sent from my iPhone using Tapatalk

Author:  SteveSmith [ Mon Aug 12, 2019 2:01 pm ]
Post subject:  Re: Edge sander woes...

An ohm meter puts out a voltage for testing then reads the result across the resistor on an ammeter per the formula volts=ohms x amps, a good cap will slowly charge until it is at max volts which will read max ohms on your multimeter. Looks like your cap is probably bad or at least leaky.

Author:  meddlingfool [ Mon Aug 12, 2019 2:28 pm ]
Post subject:  Re: Edge sander woes...

Well that’s good news then as it’s easily replaced (I think)

Author:  meddlingfool [ Mon Aug 12, 2019 3:12 pm ]
Post subject:  Re: Edge sander woes...

Well that's interesting. When the capacitor is detached to the machine, the readout streadily goes up to read about 1650 then hovers there. When re attached to the machine, I get a read of 300 dropping to zero...

Author:  banjopicks [ Mon Aug 12, 2019 3:32 pm ]
Post subject:  Re: Edge sander woes...

That's because your measuring the motor windings when it's attached.

Author:  meddlingfool [ Mon Aug 12, 2019 3:42 pm ]
Post subject:  Re: Edge sander woes...

Ah I see. So doing it attached to the machine is no good then.

Steves post above makes me think that perhaps the cap is good then, as when tested off the machine the ohms steadily climb?

Author:  SteveSmith [ Mon Aug 12, 2019 4:01 pm ]
Post subject:  Re: Edge sander woes...

Gotta be detached.

Author:  meddlingfool [ Mon Aug 12, 2019 4:04 pm ]
Post subject:  Re: Edge sander woes...

Am I right in thinking that it's probably good as there are no bulges and leaks, and when detached, the ohms steadily climb on the tester?

Author:  SteveSmith [ Mon Aug 12, 2019 5:33 pm ]
Post subject:  Re: Edge sander woes...

if you are on the 2000 ohm scale and the ohms climb up to the max scale reading then the cap is probably good.

Author:  meddlingfool [ Mon Aug 12, 2019 5:37 pm ]
Post subject:  Re: Edge sander woes...

It went to about 1650, do you think that's still ok?

Author:  SteveSmith [ Mon Aug 12, 2019 6:04 pm ]
Post subject:  Re: Edge sander woes...

If you can repeat the test several times (short out the cap between tests) and get the same result then the capacitor is likely ok. On the other hand, if you are trying to get the motor cleaned up to run for the next xx years you could just replace it, they're not expensive.

Author:  meddlingfool [ Mon Aug 12, 2019 7:29 pm ]
Post subject:  Re: Edge sander woes...

I'm going to get a new one and see if that helps. I can always return it. It's about the only thing I feel qualified to do. I took off the fan cover and the bottom of the motor is sealed quite well, looks like a job to get into the centrifugal switch. I'm not convinced it's the switch any way, as I can get the motor to speed by handrolling the drum, and you can clearly hear the switch click in and out which makes me think it's working but I don't know.

I'll get a capacitor and see what happens...

Author:  Bri [ Mon Aug 12, 2019 7:58 pm ]
Post subject:  Re: Edge sander woes...

I had a switch that would function like that sometimes.
It appeared that dust had built up in the switch, caused some arcing at the contacts, and over time caused enough of a voltage drop that the motor would only hum. I could get it go by helping, but would not run at full power. Of course the switch in question was actually able to be opened. I cleaned it out and ran a points file over the contacts and it all worked fine.

B

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