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Choosing between 2 block grinders

Leadberry

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Akron, OH
So I came into two CM block grinders today. I plan on keeping one and flipping the other. Which would you choose?

They're both 1/2 HP, 7". Both grinders start up without problems and purr like kittens.

Grinder #1: 397.19590. Made in 1964. Brass nameplate. Pulls 4.4 amps. Steel/glass eyeguards, work light, and quench tray. This grinder has a bit more rust, and some of the internal wiring is starting to lose insulation in chunks. Tiny bit of bearing noise on slow down.

Grinder #2: 397.1949. Made in 1973. Commercial model. Pulls 5.2 amps. Plastic eyeguards. Missing spark arresters and rubber bushings/feet. I can cannibalize these parts from the other grinder if I need to. This grinder never had a light, and possibly never had a quench tray. This one has a bit more bearing noise, and the motor is a bit noisier too.

The grinders are in pieces in the pics because they're in the process of being inspected/cleaned.

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jakemac

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I'd keep them both, but that's just me. :dunno:

But if you only want to keep one, then keep the first one. Only because I think it needs less work, and the switch is easier to replace if it goes bad. The second one has the rectangle hole for the switch, and those are harder to find. The round hole on the first one will take any similarly rated switch from the local hardware store.

As for the rotting wire insulation - You could replace the wires with something new.
Or - If you don't want to go to all that trouble, as long as the stranded wire underneath is still good, just slip some shrink tube over the wires and heat it with a hair dryer. It will hold the insulation together, and keep the wires from shorting.
 

Thumper68

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Yup keep them both, I just picked up a second one today and plan on adding it to the arsenal.
 

Lookin4'67Galaxieconv

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I'd say keep both as well, only b/c if one goes bad and you need the other, you got it...you don't have to worry about finding one again.

That being said, I like the older one though what jakemac said makes sense.
 

Tronyadorable

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Grinder one. Coarse stone/fine stone
Grinder two. Coarse wire/fine wire(or buff--or mod the right side into a belt sander)
 
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drivesitfar

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unless you need the money i'd keep both and have 4 different wheels on them like has already been mentioned.

there is plenty of rebuild threads on these Craftsman blocks if you want to spend the time. of all the posts I've read on the Block thread i'd have to say i haven't seen one member disappointed after doing a rebuild on one of these old dependable grinders.

the commercial version can be wired for 220 if you choose to do so and i think i have the manual for mine showing how to do so if you would like to try that option.

they both look like great grinders.
 

Davefr

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It's a no brainer. Keep the commercial version if you can only have one. Higher amps, one less tool rest to make, 220V capability and the commercial versions usually have guards that will accomodate 6" and 7" wheels.

However it's nice to have dedicated grinders each for grinding, wire brushing, buffing and knife sharpening.
 

jakemac

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The first one is an "Industrial". The second is a "Commercial". This seems to be indicative of how the early -vs- later higher end machines were labeled. For all intents and purposes there is no difference that's been found between the two. They're both built like tanks.

Both motors are dual voltage.

Except for the age difference, a few material changes, and a slightly higher amp rating on the second one, they're the exactly the same machine.
 
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Leadberry

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Akron, OH
I guess I'm keeping both...I like the idea of sticking wire wheels on one of them. I'll have to make up another stand though, or maybe one stand that I can mount both grinders on.

However, I'm running into a couple snags cleaning up the first one:


1. This is the wire with the rotting insulation:

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As you can see, it's coming out of the stator, and I'm not sure I can replace it. This is the only wire that's rotting--all the others are in great shape. What would be the best way to handle this? I'm debating using insulating glue/epoxy (hot glue?) to keep it from shorting against the windings, then using heat shrink tubing along the rest of the wire. I don't know how long the wire would last without being replaced.


2. For anyone who has pulled the bearings from the rotor shaft, how do you get those suckers off of there? They're on tight, and I don't want to risk damaging the shaft.
 

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jakemac

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Just slip the shrink tube over the wire and try to work it down the wire into the stator as far as you can get it.
 
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