let's see your craftsman block grinders

[Cruzan80]

The only really "rare" ones, I believe would be the Long C (the 1/2 is much harder to find than the 1/3, IME), and the "pre-block" with the quench tray and built in lights. I know some people think highly of the 3/4-1HP, but as Frank showed, not sure they are any more powerful than the 1/2HP early versions.

 

[ching0n]

The more hp, the more desirable(?). I believe that the 1/3 and 1/2 hp square-top models are the most common. The 3/4 and 1 hp models are less common and generally more money.

However, IMO, the earlier round-top cast-iron models should be a quest grinder.

I have and use both a 1/3 hp, 397.19391 square-top and a 1/3 hp, 115.7566 cast iron. The 7566 is my favorite, by far.




Below is a rotor assembly from a 1/3 hp square-top grinder.





Below is a rotor assembly from a 1/2 hp, 115.7575 cast iron grinder.





Here they are side-by-side. This is why I prefer the cast iron models.

this is what's available near me:
397.19590 1/2
397.19400 1/4
397.xxxx 1/3
397.19440 1/2
397.19391 1/3
397.19571 1/4
397.19340 1/2
257.192190 1 hp
397.19430 1/2
118.7561 1/4 cast iron

 

[ching0n]

The only really "rare" ones, I believe would be the Long C (the 1/2 is much harder to find than the 1/3, IME), and the "pre-block" with the quench tray and built in lights. I know some people think highly of the 3/4-1HP, but as Frank showed, not sure they are any more powerful than the 1/2HP early versions.

are the smaller and/or earlier smoother than the new ones, stuff like that?

 

[Cruzan80]

More like they over built them. If you look at the size of the windings, they get progressively thinner and pull less amps.

For the two I listed, the Long C are more Baldor-shaped, and the other one is "different" enough (quench tray built in to the middle, lights, etc.)

 

[ching0n]

More like they over built them. If you look at the size of the windings, they get progressively thinner and pull less amps.

For the two I listed, the Long C are more Baldor-shaped, and the other one is "different" enough (quench tray built in to the middle, lights, etc.)

most of these look like die cast pot metal. Some older ones look like cast iron.

 

[Outlawmws]

most of these look like die cast pot metal. Some older ones look like cast iron.

While correct, what matters is the winding and armature. the "Block" grinders are generally excellent and way better than Asian imports.

I have the 1/2" HP "Craftsman Industrial" and its one of my best grinders, if not the best.

 

[Old Radar]

are the smaller and/or earlier smoother than the new ones, stuff like that?

If by "smoother" you mean less vibration, not necessarily.
As long as the shaft is straight, you can reduce/eliminate the vibration of most quality grinders by balancing the wheels--especially wire wheels, which are notorious for their lopsidedness.

This link will show how much lead I needed to balance a wire wheel on my old 1/3hp Baldor. From there you can follow a link to my balancing method. You can also do a Google search for Balancing Grinder Wheels.

BTW, I can attest that my 1/2hp cast iron 115.7575 is much more powerful than my newer Block 1/2hp 397.19591.
Good Luck!

 

[ching0n]

If by "smoother" you mean less vibration, not necessarily.
As long as the shaft is straight, you can reduce/eliminate the vibration of most quality grinders by balancing the wheels--especially wire wheels, which are notorious for their lopsidedness.

This link will show how much lead I needed to balance a wire wheel on my old 1/3hp Baldor. From there you can follow a link to my balancing method. You can also do a Google search for Balancing Grinder Wheels.

BTW, I can attest that my 1/2hp cast iron 115.7575 is much more powerful than my newer Block 1/2hp 397.19591.
Good Luck!

I'll look through the cast iron ones and keep my eyes peeled for a 1/2 hp unit. I think I spotted one but wasn't sure due to quench tray differences. As far as I can tell on the cast iron, 1/4hp came w/o tray, 1/3 hp integral to body, and 1/2 hp w/a weird rod pivot tray? Looks like the cast iron units were made by Packard/GM. I think I read the new ones were Emerson.

Looks like 397.19441 was too but maybe that was a mistake in the db or an odd duck before switching:

Packard Electric Co. | Packard Electric Division - General Motors Corp. - Photo Index | VintageMachinery.org

 

[FrankLee]

As far as I can tell on the cast iron, 1/4hp came w/o tray, 1/3 hp integral to body, and 1/2 hp w/a weird rod pivot tray?

The 1/4 hp did not have quench tray, side wheel covers or lamp.

The 1/3 hp did not have quench tray or lamp.

The 1/2 hp had a quench tray and tool rests built into a separate base. The lamp was threaded into the rear of the left motor end cap.

 

[ching0n]

The 1/4 hp did not have quench tray, side wheel covers or lamp.

The 1/3 hp did not have quench tray or lamp.

The 1/2 hp had a quench tray and tool rests built into a separate base. The lamp was threaded into the rear of the left motor end cap.

this is the 1/3 hp cast iron one I'm seeing. It also appears the cast iron ones are more affectionately known as "tombstone/mailbox" and not "block". So maybe the real question is tombstone vs block, which one's better?

More resources:

Craftsman Block motor Bench Grinders - What's the Fuss (with resource information)

Due to Photo Buckets change in 3rd-party hosting policy, many/all images below may not appear. December 30, 2017 Due to a complete system failure at other sites, some of the threads, as well as pictures are not active/available. I regret the inconvenience. Other CM Block grinder related...

www.garagejournal.com

 

[FrankLee]

I forgot about that model. (1948? to 1953)
Yeah, that 1/3 hp has all the features.

 

[Old Radar]

cast iron ones are more affectionately known as "tombstone/mailbox" and not "block"

You and @Caveman613 should get together and hammer out the names we can all recognize them by.

 

[Outlawmws]

I'll look through the cast iron ones and keep my eyes peeled for a 1/2 hp unit. I think I spotted one but wasn't sure due to quench tray differences. As far as I can tell on the cast iron, 1/4hp came w/o tray, 1/3 hp integral to body, and 1/2 hp w/a weird rod pivot tray? Looks like the cast iron units were made by Packard/GM. I think I read the new ones were Emerson.

Looks like 397.19441 was too but maybe that was a mistake in the db or an odd duck before switching:

Packard Electric Co. | Packard Electric Division - General Motors Corp. - Photo Index | VintageMachinery.org

From my Notes:




I Don't have dates for Delco/397:

 

[FrankLee]

The round-top model first appeared in the 1948? catalog and lasted through the 1975/75 catalog.

The square-top first appeared in the 1974/75 catalog for the 1/2 hp model.

The cast iron grinders last appeared in the 1963 catalog. Thereafter they were cast aluminum.


(post-block, block, pre-block, pre-pre-block - wgaf)

 

[ching0n]

...

(post-block, block, pre-block, pre-pre-block - wgaf)

it goes to the question of "who made them" and was the design different enough to prefer one over the other is all. Cast iron has much better damping properties than aluminum for instance. You seem to have recognized the rotors were also different. They can be called toasters for all I care.

 

[IRQVET]

Asking the experts, dude is selling this locally with the iron stand, won't budge from $100.

Is it worth it?

 

[Cruzan80]

From the exterior, I would be worried about how well it will work long-term. Looks like it was exposed to a lot of moisture

 

[JMP]

Asking the experts, dude is selling this locally with the iron stand, won't budge from $100.

Is it worth it?

It has the matching stand. The stand alone can sell for that or more to the right buyer. It's a shame that the grinder is so roached. Does it work? Maybe not a great deal but I wouldn't say it's a bad deal. Just depends on what you are after. Something to use, parts, or a restoration project.

 

[IRQVET]

It has the matching stand. The stand alone can sell for that or more to the right buyer. It's a shame that the grinder is so roached. Does it work? Maybe not a great deal but I wouldn't say it's a bad deal. Just depends on what you are after. Something to use, parts, or a restoration project.

Use mainly. I can strip and repaint it, but not a full restore. It's a little rough, but I have two concerns . . .

1/3 HP might be underpowered for metal grinding?
And of course cause I haven't seen it run, is the running condition. To say it runs is one thing, running well, that's different.

 

[IRQVET]

From the exterior, I would be worried about how well it will work long-term. Looks like it was exposed to a lot of moisture

It's Florida, our humidity is a killer, unless things are stored in climate controlled environments 24/7.

 

[Cruzan80]

I grew up in GA, so understand the humidity. Even with that, it looks like it was rode hard, IMO.

 

[JMP]

Use mainly. I can strip and repaint it, but not a full restore. It's a little rough, but I have two concerns . . .

1/3 HP might be underpowered for metal grinding?
And of course cause I haven't seen it run, is the running condition. To say it runs is one thing, running well, that's different.

Yeah if you just need one to use right now I would maybe keep looking. In parts though it maybe makes sense to some. Most of these bench grinders are missing the lamp, stand, or quench tray so in parts it definitely could make sense to someone. I have a 1/3 and a 1/2 and the 1/3 is probably overkill for me but I'm not some heavy duty metal worker. Doesn't hurt to have more power I guess.

 

[rockinacummins]

My first Craftsman Block. Been quietly looking for one since I joined GJ and saw this thread. $25 at an estate sale.

 

[Toolguybak]

So maybe the real question is tombstone vs block, which one's better?

Different factors to consider.
The Packard built cast iron "tombstone/mailbox" grinders are rugged and smooth. The last iterations used a start relay in place of the centrifugal switch. As previously mentioned, only the largest 7" grinder had a quench tray and lamp.
The subsequent Delco built die-cast (tombstone/mailbox) aluminum grinders mimicked the cast iron machines but couldn't absorb vibration like the previous models, especially with larger wheels. They are still nice, rugged grinders. Lamps and quench trays were available on all sizes. (Side note: the early model 1957 1/4hp 6" basic machine had a 2-wire power cord and no off/on switch.)
The Delco built die-cast aluminum "block" grinders (appearing in the mid-1970s) improved the vibration characteristics with shorter rotor shafts and stiffened end bells. These are nice, rugged grinders. Like the previous models, quench trays and lamps were available.

 

[ching0n]

Different factors to consider.
The Packard built cast iron "tombstone/mailbox" grinders are rugged and smooth. The last iterations used a start relay in place of the centrifugal switch. As previously mentioned, only the largest 7" grinder had a quench tray and lamp.
The subsequent Delco built die-cast (tombstone/mailbox) aluminum grinders mimicked the cast iron machines but couldn't absorb vibration like the previous models, especially with larger wheels. They are still nice, rugged grinders. Lamps and quench trays were available on all sizes. (Side note: the early model 1957 1/4hp 6" basic machine had a 2-wire power cord and no off/on switch.)
The Delco built die-cast aluminum "block" grinders (appearing in the mid-1970s) improved the vibration characteristics with shorter rotor shafts and stiffened end bells. These are nice, rugged grinders. Like the previous models, quench trays and lamps were available.

Thank you for the input. Do you think the later Delco block grinders rival the cast iron units in vibration? What about the guts, it seems to be from what I'm reading that the cast iron units had beefier comps and more perceived power.

 

[JMP]

Thank you for the input. Do you think the later Delco block grinders rival the cast iron units in vibration? What about the guts, it seems to be from what I'm reading that the cast iron units had beefier comps and more perceived power.

I have both types but have not used my cast iron one yet since it's in pieces as I attempt to recondition it. One of the things I have found is that the arbor washers on both of my grinders are just cheap stamped pieces of metal. The outer arbor washers used on my WW2 era cast iron grinder look they are putting uneven pressure on the stones blotter paper so I am looking to have these parts replaced with CNC made parts to in theory reduce vibration and potential stone damage. I am hoping with these new parts along with some brand new freshly dressed stones and maybe new bearings I'll have the smoothest running Craftsman cast iron grinder in town. I have seen some machinists/hobby machinists face their arbor washers and nuts perfectly flat with a lathe for their fancy industrial Baldor grinders. Another thing I have seen are custom machined arbor washers with an inner track filled with ball bearings. Apparently this helps with self balancing, especially when used with way off balance wire wheels. In short there are things you can do with even the cheapest grinder to help them run smoothly.

 

[DrFeelGood]

I didn't get around to posting my grinder find this last summer but I found one (397.19440) on FB for $15 . A retired fellow said it was an extra he had when he closed his tire shop. By the time I got there, (45min) he said had had received 20+ requests.



I add the above now, because I grabbed another (397.19580) $20 one this week.



One goes to my dad for his new house and the other goes to my neighbor.
Thanks for looking.

 

[harley jim]

I hope I don't get smacked for this but I had to have a grinder!

This was given to me several years ago and I had intentions of restoring it, but I needed one to add to a project I'm working on.

It runs great, as do most of these, but the guards are missing. I was able to find part of one guard about a year ago.

I had a set off something else so I redrilled them,

Had to make some spacers.


It works! I'm going to put a fine stone on in place of the wire wheel and make a jig for sharpening drill bits.
I'll keep looking for the right guards and put it back to stock someday.

 

[harley jim]

Finished the grinder/polisher today.

Grinder on this side.

Polisher on this side!

 

[seagiant]

Hi,
Picked up a FB Buy, Craftsman Block Grinder for $25...

Decided to make a Lathe Tool Sharpening Station for my Machine and Wood Lathe tools.

Rebuilt the Grinder with new Bearings, and then made some Rests from Scrap Steel I had, not in the best shape but usable.

Nothing fancy but works great and I can set the exact angle I want now.

Have a Green Wheel for Carbide and an AO Wheel for HSS..

Worth the effort and should of been done sooner!

 

[ching0n]

picked up a '1/4 hp' cast iron unit for 15$. It's missing the eye guards but has a new chord and runs pretty smooth. Fairly rusty so may give rust reforming paint a shot instead of removing the rust. Any "upgrades" one ought to consider for these units? Mine's like this one basically:

 

[LNKMK8]

I came across this nice all original 3/4 HP Craftsman Commercial unit last month... it cleaned up well. I dressed the original wheels but there is still a fair amount of vibration present. Has anyone found an effective way to smooth one out? I've had some that have run perfectly smooth and others that vibrate quite a bit.

 

[Old Radar]

Have you tried running the grinder without the stones? This will tell you whether the stones are the real culprit. If it settles down without the stones, get new stones (you really should anyway...). If not, check the spindles--they may be bent or something may be riding on one. In one of my tune-ups I found two oversized steel washers inboard of one stone, spinning loose on the spindle--you never know what a previous owner might have added to "improve" performance...

 

[JMP]

I came across this nice all original 3/4 HP Craftsman Commercial unit last month... it cleaned up well. I dressed the original wheels but there is still a fair amount of vibration present. Has anyone found an effective way to smooth one out? I've had some that have run perfectly smooth and others that vibrate quite a bit.

Try running one stone at a time to try and isolate. Is the blotter paper in good shape on these stones? I bet the paper is pretty torn up by now if those are the original stones. Also these flanges are just stamped parts. Precision grinding machines often have CNC made / faced flanges and nuts.

Also wow that machine looks brand new.

 

[LNKMK8]

Thanks guys, I'll do a little more investigating when I find some time. I did take a quick look at one side and everything appears to be very clean and orderly, but hard to say until I actually pull it apart.

 

[FrankLee]

I came across this nice all original 3/4 HP Craftsman Commercial unit last month... it cleaned up well. I dressed the original wheels but there is still a fair amount of vibration present. Has anyone found an effective way to smooth one out? I've had some that have run perfectly smooth and others that vibrate quite a bit.

Do your wheels have those ribbed plastic nesting arbor spacers? I never had confidence in those to maintain wheel balance.
Some adapters are better than others. I would use these before those plastic bushings.
https://m.media-amazon.com/images/I/61TrtLH+r7L._SL1316_.jpg

 

[LNKMK8]

Do your wheels have those plastic nesting arbor spacers? I never had confidence in those to maintain wheel balance. Some are better than others.
I would use these before those plastic bushings. https://m.media-amazon.com/images/I/61TrtLH+r7L._SL1316_.jpg

I'll have to take a look.. I'm guessing not since they are original. I agree, I don't care for them either. I have used some metal ones on my other grinder with success.

 

[ching0n]

Can someone confirm if 397.19430 bearings are 6203 2Z C3 17x40x12 mm? Any other part numbers that may fit?

Thank you,

 

[Bobioz1]

Can’t believe nobody answered your question yet. There’s a block grinder resource thread on here somewhere. Find it and it will answer any questions you have.

 

[torqueman2002]

Can someone confirm if 397.19430 bearings are 6203 2Z C3 17x40x12 mm? Any other part numbers that may fit?

The arbor size is 1/2" and it does use a 17x40x12 mm bearing.

Here's a NTN bearing look-up link.
https://bearingfinder.ntnamericas.com/advanced/all-categories

I've used these, from AZ. (~$13ea + shipping)
https://www.amazon.com/dp/B00DBOIX7E?tag=atomicindus08-20