Sears Craftsman Bench Grinder - any worth?

[freebo86]

Figured I could use a bench grinder in the garage.. sourced this on marketplace. When I got there I realized this things bigger than I expected. My garage space is limited.. ‍♂

Figured since I went there I picked it up anyways, $20.

1/2HP, Sears Craftsman, I pulled one of the wheels off its 7”, arbor size 5/8s. The wheel I pulled off seems to be for aluminum, the other wheel I think says steel on it. The light even works. when I run it and turn it off it spins forever until it stops. Looking online these things are listed as 6” grinders so I’m a bit confused now why there is a 7” wheel and it looks to be original.

Should it actually be running 6” wheels? I was thinking of cleaning, and repainting the larger parts (mini-resto). Need to replace the cord on it as it’s frayed. But would like to know if it’s worth it before I dive in.

Thanks!

 

[gilbo]

You can be the judge if these are worth anything

 

[RoninB4]

The wheel I pulled off seems to be for aluminum,

-If this is the wheel you interpreted as "for aluminum" I can assure you that it is NOT for grinding aluminum. Aluminum oxide wheels are very common but used for steel and ferrous materials only. If you want to know why just ask, I'll tell you and you'll be sorry you asked.

Attempting to grind aluminum with this wheel will quickly clog the wheel with material and render it almost useless. If enough material clogs the wheel there's even a chance the wheel will explode when the aluminum expands with heat, very dangerous when that happens. There are other abrasive wheels (silicon carbide) for non-ferrous materials but I wouldn't suggest the average consumer use these as they're very soft and aimed at industrial applications. How to tell some novice has attempted to grind aluminum? The wheel begins to look like this.


The only solution for this condition is to dress the wheel until ALL the aluminum comes off. Before anybody replies that they've ground aluminum in a bench grinder with an Al2O3 wheel please spare yourself the embarrassment of revealing that you're an idiot that should not be allowed around a bench grinder without adult supervision. If you must somehow abrade a non-ferrous material (aluminum, brass, some SS, etc.) use a flap wheel, sanding belt, or some other type of abrasive. A clogged bench grinder wheel immediately confirms that there's an idiot in the shop/garage.

 

[Lassen Forge]

Um, it's not FOR grinding aluminum, the abrasive is Aluminum Oxide.

Silicon Carbide is used for non ferrous, but are a whole different animal, and can get expensive even WHEN used correctly.... I have a set of SiC wheels for my grinder, but don't mount them unless I'm working with bronze or aluminum or some other NF metal.

 

[fatfillup]

$20 for an 1/2 hp Cman block grinder.
That's approaching suckage status, many would say you do ****

I sell those from $50 to $80 depending on condition and buy every one I can.

Bought an absolutely filthy one last week at an auction for $5. Needs wheels but runs fine

Enjoy

 

[seber]

If the wheel fits and the speed does not exceed the RPM listed on the wheel, you are fine. As Ronin stated, NEVER grind aluminum on a bench grinder. And it does not matter what type of abrasive the wheel is made from. Just don't do it.

 

[freebo86]

Thanks for the info and link! So seems these are somewhat sought after.. lol.

I was tired and late, I only realized after that the aluminum was what the wheel was made of lol and not what it’s FOR! Appreciate the feedback, won’t be grinding aluminum. I may swap one of the wheels for a wire brush one, and still want to see what the other wheel actually is as I do see the wording steel on it..

I looked through the thread linked, seems that this unit is mostly complete besides the rubber feet missing.

I think I’ll strip it down, clean up the hardware, repaint in a proper “grey” tool color, lol and keep it. I think it may need to have the wheels dressed as it does somewhat move around a lot when it runs.

 

[fatfillup]

Dress the wheels outside, makes a lot of dust

 

[1982fxr]

-If this is the wheel you interpreted as "for aluminum" I can assure you that it is NOT for grinding aluminum. Aluminum oxide wheels are very common but used for steel and ferrous materials only. If you want to know why just ask, I'll tell you and you'll be sorry you asked.

Attempting to grind aluminum with this wheel will quickly clog the wheel with material and render it almost useless. If enough material clogs the wheel there's even a chance the wheel will explode when the aluminum expands with heat, very dangerous when that happens. There are other abrasive wheels (silicon carbide) for non-ferrous materials but I wouldn't suggest the average consumer use these as they're very soft and aimed at industrial applications. How to tell some novice has attempted to grind aluminum? The wheel begins to look like this.


The only solution for this condition is to dress the wheel until ALL the aluminum comes off. Before anybody replies that they've ground aluminum in a bench grinder with an Al2O3 wheel please spare yourself the embarrassment of revealing that you're an idiot that should not be allowed around a bench grinder without adult supervision. If you must somehow abrade a non-ferrous material (aluminum, brass, some SS, etc.) use a flap wheel, sanding belt, or some other type of abrasive. A clogged bench grinder wheel immediately confirms that there's an idiot in the shop/garage.

I've bought and sold a LOT of used bench grinders. My hypothesis based on years of field research is that all Grinding wheels must have come from the factory with aluminum in them.

 

[RoninB4]

-Just for additional info, the silicon carbide wheels are often a green color. They can also be used for rough grinding carbide (cemented carbide lathe bits, insert touch up. carbide end mill relief, etc.) but they don't leave a very good finish for a cutting edge. The edge will be rough and serrated under magnification. Just thought someone would want to know.

 

[RoninB4]

My hypothesis based on years of field research is that all Grinding wheels must have come from the factory with aluminum in them.

-I can see where your field data might have led to your conclusion. You'd also have to include the sheer number of idiots out there in with access to those wheels. I've run into them in machine shops where they ought to know better (but didn't seem to).

 

[freebo86]

Pulled the other wheel, same type of wheel. I managed to preserve the tag on this one, grit #36.

I’ve dismantled the unit fully. The bearings seems solid, no odd noises or movements from them.

 

[Nutria]

when I run it and turn it off it spins forever until it stops.

That is not necessarily a good thing. People assume that this means that the bearings are in good shape, and they might be. More likely: the bearings are bone dry-- the original grease either gone or turned to stone-- so there's no resistance. I'd have a look at the bearings and verify. It's sometimes possible to regrease if the originals are high-quality. Otherwise, order in some good replacements from Accurate or elsewhere.

Nice grinder; good luck.

 

[sk farmer]

somebody picks up a nearly 100% complete 1/2 hp block grinder that has original wheels meaning almost no use for 20 bucks and doesn't get a you ****?

 

[1982fxr]

That is not necessarily a good thing. People assume that this means that the bearings are in good shape, and they might be. More likely: the bearings are bone dry-- the original grease either gone or turned to stone-- so there's no resistance. I'd have a look at the bearings and verify. It's sometimes possible to regrease if the originals are high-quality. Otherwise, order in some good replacements from Accurate or elsewhere.

Nice grinder; good luck.

This is essentially advising everyone with a good running grinder that has a long spin down time (whatever that might even mean) thar they need to do a teardown to inspect bearings.

Totally ridiculous. He didn't even say how long forever is. That could mean anything to anyone. Again, totally ridiculous.

 

[freebo86]

So I looked closer at the bearings, while in hand there is zero resistance and the bearing when armature rod spins. The bearings are 6203Z Nachi NB Japan.

Being a smart a&& I removed one of the bearings. I’ve had luck in the past greasing metal shield bearings by drilling a small pilot hole in the shield and then injecting grease using my needle adapter. Well did that and now there is a ‘notch’ felt when I spin it..

Would these Timken be good replacements?

2PCS TIMKEN 6203-ZZ Double Metal Seal Bearings 17x40x12mm Ball Bearings : Amazon.ca: Industrial & Scientific

2PCS TIMKEN 6203-ZZ Double Metal Seal Bearings 17x40x12mm Ball Bearings : Amazon.ca: Industrial & Scientific

www.amazon.ca

 

[Nutria]

So I looked closer at the bearings, while in hand there is zero resistance and the bearing when armature rod spins. The bearings are 6203Z Nachi NB Japan.

Well, you'll certainly have lots of options for 6203 replacements-- super common. I like to replace bearings in machines that will see abrasive dust with sealed bearings (2RS), even though there is slightly more drag with the sealed bearings. Others prefer the ZZ shielded bearings. Probably not a big deal either way.

Nachi and Timken are both fine names. I think that the COO has changed for both, but I think that quality control remains good. I personally would prefer not to buy bearings from Amazon, though you might have good luck there. Consider contacting the competent and pleasant folks at Accurate Bearing-- family business, and they may well have a competitive price for you. I've probably purchased over a hundred bearings from them. They pay attention to their product, so you can trust what they sell you.

Enjoy your project and using that cool grinder.

Bearing Supplier Leader In USA & International | Same-Day Shipping

Top US & international bearing supplier of electric motor bearings and power transmission parts with no minimum orders and same-day shipping. Accurate Bearing Company is the industry's value leader.

www.accuratebearing.com

 

[fatfillup]

somebody picks up a nearly 100% complete 1/2 hp block grinder that has original wheels meaning almost no use for 20 bucks and doesn't get a you ****?

See post 5, I more or less did

 

[1982fxr]

Well, you'll certainly have lots of options for 6203 replacements-- super common. I like to replace bearings in machines that will see abrasive dust with sealed bearings (2RS), even though there is slightly more drag with the sealed bearings. Others prefer the ZZ shielded bearings. Probably not a big deal either way.

Nachi and Timken are both fine names. I think that the COO has changed for both, but I think that quality control remains good. I personally would prefer not to buy bearings from Amazon, though you might have good luck there. Consider contacting the competent and pleasant folks at Accurate Bearing-- family business, and they may well have a competitive price for you. I've probably purchased over a hundred bearings from them. They pay attention to their product, so you can trust what they sell you.

Enjoy your project and using that cool grinder.

Bearing Supplier Leader In USA & International | Same-Day Shipping

Top US & international bearing supplier of electric motor bearings and power transmission parts with no minimum orders and same-day shipping. Accurate Bearing Company is the industry's value leader.

www.accuratebearing.com

Congratulations on getting a guy to tear down a perfectly running machine with total ********.

I hope others don't follow.

 

[mreisner]

Congratulations on getting a guy to tear down a perfectly running machine with total ********.

I hope others don't follow.

My dad brought one of those grinders new in 1974 and I remember as a kid marveling how long it would take for it to spin down once it was shut off. It's been bolted to the same spot since that day in 1974 in an unheated shop and saw a lot of rough use for half a century and still takes forever to spin down. I buy every one of those grinders I see at estate sales garage sales Etc. I've got probably a dozen of them and I don't think I have paid more than $25 for any one. I don't need more than two or three of them, but I like to know I'll never run out of them, and anything new with the Craftsman name on it in a grinder is ****.

 

[freebo86]

Well I pulled the shield off the bearing I drilled the pilot hole. The shield had pushed in a bit where the hole was drilled so maybe it was catching on the ball bearings a bit. I used a small grinding stone and got rid of the burr on the inside of the shield also flattened the shield with a socket.

Put the bearing in some diesel overnight to see if I can get it to break down whatever is inside of it and then I’ll add some new grease and see if I can preserve it. Hate getting rid of Japanese bearings.

 

[freebo86]

I ordered the Timken on Amazon, will see what arrives. The Nachi bearing is still in diesel I’ll try to grease it tomorrow and see if it’s smooth again.

The power cord on this unit was cut and spliced, bare wire was exposed, lol. Grabbed new cabtire 16/3c cord today, wanted 18/3 but they didn’t have any so went up a gauge. The plug end will be non original of course..

Got the covers wire wheeled and washed in dawn soap. Applied a coat of primer this evening. The housing will be Krylon Metalic Dark Metal, the center piece that has the sticker - not sure yet.