Repairing a belt/disc sander

[@1bowmaniam]

It's crazy that 99.9% of all tools end up in the trash just because of a super simple fail like that. Thank you for the inspiration!

[@jb-ik8sj]

Thanks. After losing all hope that my collection of capacitors were ALL bad, i checked that relay. Sur as shit the plunger is so corroded, the rust has locked it into place. Its soaking as i write this. I was just about to scrap this old sander. But maybe it'll work yet.

[@MB0807US]

Nice work buddy! I just rescued a non-working Craftsman 1/3 HP sander with a non function power switch. Thanks for the pointer on the relay.

[@buffordevans6942]

Mayank Bhargava How did you fix the switch ? I’ve got one that is floppy and doesn’t switch

[@rawbacon]

Back in the day Sears carried parts for the products they sold for years and years, getting a part for some old 40 y/o drill was common but not so much anymore.

[@jidissafi7413]

Great job gutting that relay/power switch on camera. It seems to be one of the most common faults with that particular unit. Some of us also have accidentally damaged ours by running with that switch in a non-vertical position, causing it to not disconnect the motor's startup winding and overheat. I don't believe mine overheated, but unfortunately, the relay wasn't doing its thing to disconnect the winding, and I had already disassembled and cleaned it. If I can get everything back together, I may try to get to the bottom of it. BTW, I just posted on another video that the Grizzly G0547 looks to be an exact match if you need parts. There are a bunch of clones from that family, but most have a couple minor differences here and there. Much Thanks!

[@DustinRogersinMO]

Good to know about the Grizzly parts availability. That may help some others out. Thanks for watching.

[@jidissafi7413]

Dustin, I ran across another one the other day that looks to be an exact clone- the GMC (Global Machinery Corp) BD1500. Somehow I get a strange feeling they wouldn't be easy to get stuff from though. I've already gotten a pulley for it from Grizzly which was no problem. I managed to get the belt drive section back together today, and unfortunately that relay still isn't dropping the start coil offline. I'll go back into that switch soon, but I'm hoping I haven't damaged the motor windings yet by letting it heat up a few times. Thanks again for the relay info!

[@timwhite9255]

I just found your channel and already you have two of the same tools i use and you already helped with the one and taught me about the sander relay. Awesome. I am subscribed.

[@DustinRogersinMO]

Awesome. Thanks for subscribing.

[@dubyad4d288]

Thanks for the break down. It would be very helpful to show the wire connections from the switch to the relay before putting it all back together.

[@m1ame0w]

I was going to mention exactly the same thing. Which wires go where?

[@ramonmichaud3004]

Dustin, You may want to clean up the contacts inside the start / stop switch. both relay and switches were bad on my unit. cheers

[@gregd.88]

Just got my craftsman 4x6 working this afternoon. I had a loud sqeeling noise from the idler roller on the belt. As you know, bushings not available. I found some bushings from another sander turned theem down to press onto the bore on the roller then bored the inside to fit. Put it back togeather. It worked like new.

[@DustinRogersinMO]

Greg Darling nice. My idle roller squeals like crazy too. Any idea what bushings you used?

[@gregd.88]

The bushings I used came out of an older craftsman belt sander I bought at a yard sale. No model number was found on that unit though.

[@zackarysena4366]

I suspect solutions in repairing these are easy (even if parts can't be found through regular channels). Buying one of these older ones tomorrow for making small accent parts for vintage trim restoration work? Thanks for this heads up (and will be proactive finding minor repair solurions).

[@paulcotesr5623]

I have a sander like that .when i turn it on it sits and hums if i help it by pushing the belt to get it to go it works . Any idea what it night be the contact in the relay are clean please any help ty Paul

[@DustinRogersinMO]

I’d suspect a bad capacitor which is typically required to give a little “boost” to get it started.

[@paulcotesr5623]

@@DustinRogersinMO sorry it dont have a cap ,all it has is a switch ,relay and motor the relay sound like it connecting i look inside the the relay all like new

[@skchen83]

Nice job. You see combo sanders like these on Craigslist all the time.

[@DustinRogersinMO]

Thanks. Unfortunately in my area, people assume everything is trash and they pitch it. I could fix stuff like this all day long if people would just list it instead of tossing it. Thanks for watching.

[@danthemakerman]

Thank for sharing man, its a good feeling when you can fix something!

[@jbrondos]

I get a hum when I turn on the power switch, but the motor won't turn. the belts turn freely - but the motor doesn't spin. One difference between your sander and mine seems to be a fairly large capacitor in line. Could that fail?

[@DustinRogersinMO]

jbrondos it’s possible. Certain types of motors require a start capacitor. It uses the stored energy in the cap to give it a little boost to get going. There are tools that can test capacitors, but they’re usually cheap enough to just replace. Get one that has the same capacitance rating and is rated for at least as many volts as the current cap. You may also pay attention to any positive/negative markings as some capacitors are polarity specific.

[@dennisr1683]

Great video - many thanks!

[@evanthompson8925]

Great video. Wonder is the sander would properly function is the relay was bypassed?

[@DustinRogersinMO]

Evan Thompson not sure.

[@darcyvaughan4884]

Generally you don't want to bypass a relay. The motor draws a high amperage current through it, particularly when starting up. The relay is used to prevent this high current from passing through the switch as it will burn it out eventually. Certainly could be done as part of troubleshooting however.

[@sixtyfiveford]

Nice fix.

[@realbay2po]

Did this model have a capacitor? We have a Delta that is very similar, and has the exact same relay.

[@DustinRogersinMO]

Jeff Sheley I don't remember there being a capacitor on this one.

[@MrUltimate49er]

Nice work!

[@zipbentley920]

How do you set the tension?

[@DustinRogersinMO]

Zip Bentley tension for the belt? The tensioner arm is on the side of the belt part, opposite the disc sander side. I believe there’s an adjuster for that tensioner arm too, if the belt isn’t tight enough with the arm tensioned.

[@orsonkart9886]

Great help, thanks.

[@brendawaokforagingandadven4129]

Good to know, thank you👍😀

[@JonalistTwitMe]

What about a stuck motor?

[@DustinRogersinMO]

Michael Jones could be motor bearings are seized?

[@JonalistTwitMe]

It turns on, sounds like a fan when it seizes up due to dirt being crammed into a bearing without oil or grease. Maybe the motor could burn up so I will not turn on again till I disassemble and check out the motor completely and clean it up, still looks new hardly used, someone maybe used some metal to sand in it but the papers do not show wear, I see the dust at the small air outlet piled up. I have come across a lot of fans with the same issue and fixed then to run a few more years before them doing it again. So your suggesting I remove the bearings and clean them out using a air gun and plenty pressure then oil and replace to see if that works just as well. I will do that, I was thinking of magnetism within the motor causing the issue so you might be right on the money on this issue.

[@whitag01]

Info on why the relay between the switch and motor and why you don't want to bypass it: electronics.stackexchange.com/questions/207648/what-is-the-purpose-of-a-relay-between-a-switch-and-motor. I'm looking at one of these on Craigslist and stumbled on this video while researching it. Then I found the link above and figured I'd pass it on. Hope it helps someone. Edit: just found the manual: www.searspartsdirect.com/manual/4u8kw07lr9-000247/craftsman-113226431-power-sander

[@michschep7601]

The motors on these are notorious for burning the start windings up, and craftsman/sears offers NO replacement.........

[@myvenusinuranus]

I did it and it worked for 10 mins and then blew up