Craftsman pre-Block Grinder resto

[torqueman2002]

Here's my first attempt to get in on the CM Block Grinder fan club craze.

This 'lil Brownie was a CL find about a year ago.

I searched for parts for 'lil Brownie and wound up with a 3/4 HP CM Block Grinder purchase intended for parts: wheel cover end caps. The 3/4 HP Block grinder was put in line ahead of this 1/3 HP older brother.

Anyway here's what 'lil Brownie looked like when I brought it home.

Some parts after sand blasting.

Painted up with Rust-Oleum 249081 - Espresso Brown Ultra Cover Satin Finish. Colors are a bit off, due to blue canopy.

7715 - Aluminum Bright Coat Metallic Finish

Better picture in direct sun.

Bearings installed.

RH motor cover with start-capacitor start-up switch.

Motor ready for assembly.

Detail of centrifugal weight assembly that opens the start-capacitor switch.

At rest the black plastic bushing is extended, note inner spring. The bushing presses on the capacitor start-up switch, closing it's contacts (just like breaker points) and electrically connecting the field winding (white wire) to the start-capacitor.

As the armature spins-up, the weights swing out against the force of the small diameter springs (1 on each side). This pulls the bushing away from the start-capacitor switch, opening the contacts and the circuit.

Armature-eye view of switch.

When I disassembled the grinder, the ON/OFF switch was connected to the power cord's neutral (white) wire.

I wired the power cord's hot (black) wire to the ON/OFF switch instead; and the neutral to the capacitor where the hot had been.

The motor seems to work the same with this change. I am not a motor wiring expert - is this OK?

Red-->White = 9.2 Ohms
Black-->White = 8.1 Ohms
Red-->Black = 1.4 Ohms

Winding, power cord, ON/OFF switch, capacitor, and capacitor start-up switch wiring details.

Assembled, electrically tested, and powered-up - OK.

Next on the to-do list:
mount buffing wheels
find a goose-neck light and wire it up
think about changing the silver cover to copper

Thanks for looking.

 

[NAYLOR]

I want that. Great job!

 

[Stevedore]

Pretty thorough resto, nice job!

 

[torqueman2002]

I want that. Great job!

NAYLOR, thank you.

It makes nice whirring and clicking sounds as the mechanism opens/closes the capacitor start-up switch.

I haven't seen another like this one. I've looked for pictures, Owner's/Parts Manuals, or any reference material. Nada.

So, I thought I would put this on the forum in case someone else is looking for information on one of these guys.

Thanks again!

 

[torqueman2002]

Pretty thorough resto, nice job!

Hi Stevedore; thank you for the kind words.

I am happy to have this guy off the bench and in operation. I got side tracked with the 3/4 HP Block resto, documented elsewhere on the forum.

This one involved more in the way of updating; the bearings were marginal, the capacitor was replaced for good measure, the switch was replaced, and crimp connecters replaced soldered on connections.

It was a challenge and enjoyable.

This will do it for my grinder line up; but I'm still looking on CL. This time for one to restore for my brother.

Thanks again.

 

[throttlejunkie1]

Nice! What is that your using for a stand? Looks well suited for the job.

 

[itsvegas]

harbor freight most likely?

http://www.harborfreight.com/bench-grinder-stand-42986.html

 

[krupanut]

Very nice resto!

 

[kbkna]

WOW! Incredible restro. You sure do nice work!!

 

[Crizzle]

I have never seen one of those block grinders on CL here in Indy. Would love to find one.

 

[kissmeimgerman]

Great Work!

 

[torqueman2002]

Nice! What is that your using for a stand? Looks well suited for the job.

junkie - thanks for looking and the kind words. The stand is a Sunex grinder stand. I don't recall where I got it from, could be through tooltopia - the seller listed on this Amazon link. It's been waiting in it's box for over a year, until I completed this resto and the 3/4 HP CM Block grinder that cut-in line, ahead of 'lil Brownie.

http://www.amazon.com/Sunex-Bench-Grinder-Stand/dp/B000KQ6LXY/ref=sr_1_4?ie=UTF8&qid=1309216623&sr=8-4

 

[torqueman2002]

Very nice resto!

WOW! Incredible restro. You sure do nice work!!

I have never seen one of those block grinders on CL here in Indy. Would love to find one.

Great Work!

Man, you guys are making me blush.

I love the compliments, it did turn out nicer than I had hoped. It's fun and not overly difficult. I think stripping the paint and rust down to good bare metal makes a big difference.

RUST-OLEUM and Valspar Tractor & Implement Spray Paints do a great job of flowing and covering the metals.

Crizzle - from GF: "The "Block Motor" grinder can be readily identified by the Sears manufacturer prefix of 397 or 257 (as in 397.XXXXX); which is stamped on the front label. Popular models include 1/4HP, 1/3HP, 1/2HP, 3/4HP, and 1.0HP Industrial units."

Here's a link to the decoder-ring: http://vintagemachinery.org/Craftsman/manufacturers.aspx?sort=1

It's a site with a wealth of info; but a little tricky to navigate at first.

Enjoy!

Thanks again.

 

[bc'z]

nice re-do of a garage mainstay. That 115 prfix in the model number marks it as a Sunlight Electrical Mfg. Co. product produced for Sears & the Cman line. Great color combo.

bc'z

 

[torqueman2002]

nice re-do of a garage mainstay. That 115 prfix in the model number marks it as a Sunlight Electrical Mfg. Co. product produced for Sears & the Cman line. Great color combo.

bc'z

Well, now that's interesting. While I was composing/posting the above link to the OWWM's page saying 115 is a code for Rixon, you found info. saying it is a code for Sunlight.
Here's a link to a OWWM page saying that also!?
http://vintagemachinery.org/mfgindex/detail.aspx?id=2013

I wonder what gives?

6/28

Found this info. in the Discussion Forum regarding late 40's Craftsman grinders. May explain some of the 'mystery'. See posts 8 & 9.
http://www.owwm.org/viewtopic.php?f=77&t=97673

 

[nine4gmc]

Bumping a nice resto thread from way back!!

 

[Farmall450]

Amazing, looks MINT!

 

[hard12catch33]

Anyone know what gauge wire these grinders use to connect all the internal wiring?

 

[pendragon1998]

BUMP to the top...I know this is an older thread, but I'd like to hear a little more about the replacement wiring and the capacitor replacement.

 

[torqueman2002]

dragon,

Take a look at this restore for condenser details, http://www.thegaragegazette.com/index.php?topic=18119.msg231198#msg231198 post #17

It is OK to go up in mFd by about 10%.

Suppliers - Graingers, MSC (?), https://www.google.com/?gws_rd=ssl#q=ac+motor+capacitor+suppliers&revid=131037599

As far as replacement wiring, if the original is not brittle or cracking I leave it alone, alternatively slide on insulation or heat shrink would work where wire replacement is not possible.

Replacement wire, of course, needs to be the same gauge. Soldering is tricky on old, oxidized wire. Prep and flux are needed for a good solder joint.

I trust this answers your questions.

You can also find lots of posts and help in the let's see your craftsman block grinders thread. http://www.garagejournal.com/forum/showthread.php?t=157794

 

[pendragon1998]

Torqueman,

Thanks for the tips. I ended up tearing into my motor start capacitor and beneath the cardboard, I found it to be marked as a Mallory 70 MFD 125 VAC.

I think an appropriate replacement is this BMI 72-86 MFD 110 / 125 VAC motor start capacitor.

More pics from my restoration here (link is to my post about the capacitor).
http://www.garagejournal.com/forum/showpost.php?p=4319680&postcount=33

 

[torqueman2002]

Torqueman,

Thanks for the tips. I ended up tearing into my motor start capacitor and beneath the cardboard, I found it to be marked as a Mallory 70 MFD 125 VAC.

I think an appropriate replacement is this BMI 72-86 MFD 110 / 125 VAC motor start capacitor.

More pics from my restoration here (link is to my post about the capacitor).
http://www.garagejournal.com/forum/showpost.php?p=4319680&postcount=33

That will work, very similar to what I have used.

 

[torqueman2002]

The USPS delivered a much sought after part for Lil Brownie, today.

The missing LH wheel guard cover. Thanks to nicpw6 at OWWM!

Just a coat of Brown paint and they will be good to go.

 

[Ss95003]

So based on screen name and color and im pretty sure I just bought the RH guard of this pair off ebay. wish it was a pair as now I need the LH guard.

 

[torqueman2002]

So based on screen name and color and im pretty sure I just bought the RH guard of this pair off ebay. wish it was a pair as now I need the LH guard.

Any pictures of your grinder? It would be fun to see it.

I wish you luck, don't give up.

I'm not sure how I missed your original post, I know it's been awhile.