CM Block Grinder power switch - replacements

[torqueman2002]

Jan. 21 2018 - Because of PhotoBucket'c change in 3-rd party hosting, this thread has been edited to post pictures directly. Therefore, the first post has been split and continued begning in post #22 , below.

The Craftsman vintage grinders with Block-style-motors have a number of different switch styles, depending upon HP and year of manufacture.

For broken switches with plastic bodies and toggles like the one below, I have adapted a switch with a metal toggle.

Link to restore --> http://tinyurl.com/CM-0-75HP-397-19350-Berry

While the above fix works very well, it does take some time, material, and effort.

I want something that is a 'snap-in' solution.

I found that 3 power switches to some Bunn coffee makers will work.

The test dummies:
Left - flat-top 1/2-HP m-397.19441 with a red/black power switch,
Right - round-top 1/3-HP m-397-19581 with a black/*********** switch.

The power switch (PSW) cut-out details.

Slight narrowing in the center.

Continued on post #22, below.

 

[JZiggy]

Great resource, Dr. Block! Thanks for putting this together.

 

[torqueman2002]

Great resource, Dr. Block! Thanks for putting this together.

You betcha.

I have more related pictures I will post.

One of the terminals pulled away from the rivet. This is the same failure recently reported on 1 of the 3 sites I visit - probably OWWM/VM.

Link to thread 'CM Block Grinder power switch - repair' -->http://www.garagejournal.com/forum/showthread.php?t=310516

 

[torqueman2002]

A thread on OWWM pointed out another source for replacements switches - Graingers.

2LNA7
$12.32
Tab Terminals
https://www.grainger.com/product/PO...s:+0.250"+Quick+Connect+Tab&suggestConfigId=8

2LNA6
$4.10
Screw Terminals
https://www.grainger.com/product/PO...ctions:+2,+Terminals:+Screw&suggestConfigId=8

Link to OWWM thread.
http://owwm.org/viewtopic.php?f=77&t=166976&hilit=Craftsman+7+Bench+Grinder+Updated

 

[McBrownie]

TM,

Who made the original black/red and black/white switches? It should be embossed on the housings.

 

[torqueman2002]

TM,

Who made the original black/red and black/white switches? It should be embossed on the housings.

McB - I'll check. The OWWM poster said his search found they were not available, but maybe he just checked searsParts and eReplacemetparts.

 

[McBrownie]

McB - I'll check. The OWWM poster said his search found they were not available, but maybe he just checked searsParts and eReplacemetparts.

Here's my thought. I worked for a power tool switch company years ago. We didn't make that style, but had boxes of old stock stored away "just in case". It's a long shot, but contacting the company directly (if they still exist) might land some NOS. You never know.

 

[torqueman2002]

I forget who posted about the switch from Grainger, but here's an option.
https://www.grainger.com/product/POWER-FIRST-Rocker-Switch-2LNA7?nls=3&ssf=3&searchQuery=2LNA7

2LNA7 $10.20 / each (Jan. 22, 2018)

 

[harleybuilder]

I had forgotten about this thread , thanks Doc.

 

[torqueman2002]

You're welcome, I hope one of these work for you.

 

[StillTooManyHobbies]

Surplus center has many switches available at reasonable prices. Would either of these work for this application? I did not see the Craftsman hole size listed in the thread. These are similar in size to the Grainger unit listed.

http://www.surpluscenter.com/Electr...ches/SPDT-CO-15-AMP-ROCKER-SWITCH-11-2477.axd

http://www.surpluscenter.com/Electr...witches/SPDT-20-AMP-ROCKER-SWITCH-11-3125.axd

 

[torqueman2002]

Surplus center has many switches available at reasonable prices. Would either of these work for this application? I did not see the Craftsman hole size listed in the thread. These are similar in size to the Grainger unit listed.

http://www.surpluscenter.com/Electr...ches/SPDT-CO-15-AMP-ROCKER-SWITCH-11-2477.axd

http://www.surpluscenter.com/Electr...witches/SPDT-20-AMP-ROCKER-SWITCH-11-3125.axd

TooMany - Good information. I want to take a more detailed look at the site, to see what they offer.

I did notice that the 2 switches above are single-pole, double-throw (SPDT) center-off maintained. or ON-OFF-ON.

I added additional size information in the 1st post, picture 9.

Great find on these switches.

 

[6PTsocket]

McB - I'll check. The OWWM poster said his search found they were not available, but maybe he just checked searsParts and eReplacemetparts.

The fact that there are so many interested in replacing this switch should tell you something about the quality of the original switches. I have replaced a couple of Craftsman switches myself.While the original may neatly fit the cutout, that does not change the fact that they were low quality, cheap switches. Even if I could get one, I would not want it. I just find a quality brand that is as big or a little bigger and file a little to make it fit. Making a plate for a toggle switch is good too but a bit more work. Having a gap really looks bad to me.

Sent from my SM-G900V using Tapatalk

 

[tool_scrounge]

The grainier one look good. You would need to file the opening a bit larger, but it will fit nicely.

 

[smokey0810]

Maybe I'm missing something, but if you're not OCD on the color you can get the white one cheaper...

https://www.grainger.com/product/compare#compareSkus=2LNA7,2LNA9

 

[StillTooManyHobbies]

Thought I would post my block switch replacement. I had to file my switch opening to about 13/16" x 1 7/16" and it fits and works fine. The switch is a Carling Blodgett 1429R I bought off Ebay for about $12. It can be had for less if you like a blue rocker. It's marked as being good for 3/4hp or 20 amp 250V. It has a nice positive "snap" when it switches. I think it has a nice "vintage" look as installed.

 

[6PTsocket]

Thought I would post my block switch replacement. I had to file my switch opening to about 13/16" x 1 7/16" and it fits and works fine. The switch is a Carling Blodgett 1429R I bought off Ebay for about $12. It can be had for less if you like a blue rocker. It's marked as being good for 3/4hp or 20 amp 250V. It has a nice positive "snap" when it switches. I think it has a nice "vintage" look as installed.

I used an almost identical Carling switch I got from ebay to replace a bad one on a Sears battery charger. Same color but no ON/OFF, which was good because it is for MANUAL/AUTOMATIC. I had to file a bit, too. I already replaced the one on my grinder. There seems to be a pattern here.

Sent from my SM-G900V using Tapatalk

 

[smokey0810]

Got my white switch from Grainger installed tonight. Works like a champ!
Had to splice the main wire for the light into the power wire. About 30 min worth of filing to get it just right. Thanks for the help!
Grainger P/N: 2LNA9. $4.08 compared to $12.73 for the red which is 2LNA7

<a href="http://s1265.photobucket.com/user/jearl0810/media/IMG_2149_zpsy2qn29cy.jpg.html" target="_blank"><img src="http://i1265.photobucket.com/albums/jj505/jearl0810/IMG_2149_zpsy2qn29cy.jpg" border="0" alt=" photo IMG_2149_zpsy2qn29cy.jpg"/></a>

 

[torqueman2002]

Got my white switch from Grainger installed tonight. Works like a champ!
Had to splice the main wire for the light into the power wire. About 30 min worth of filing to get it just right. Thanks for the help!
Grainger P/N: 2LNA9. $4.08 compared to $12.73 for the red which is 2LNA7

Thanks Smokey!

Good find.

 

[Bogash]

Maybe I've missed it in these posts or maybe I'm not as sharp as you all. I have several wires to my switch. One I know is the light, no big deal there. But you all are using 2 pole switches? Can someone explain how there are converting from the cheap (broken!) switch to the 2 pole?? I have a 1/2 horse April 1973 model 397.15591. Thanks in advance!!

 

[torqueman2002]

Maybe I've missed it in these posts or maybe I'm not as sharp as you all. I have several wires to my switch. One I know is the light, no big deal there. But you all are using 2 pole switches? Can someone explain how there are converting from the cheap (broken!) switch to the 2 pole?? I have a 1/2 horse April 1973 model 397.15591. Thanks in advance!!

Sears sold bench grinders, Blocks included, for many years.

I am not familiar with 1/2 horse model 397.15591; but I have information on several 1/2-HP m-397.19591. It is a dual voltage 115V/230V model, and uses a DPST power switch.

The Block models in this thread are single voltage models - 115V, and use SPST power switches.

I would post some pictures, but PhotoBucket is not playing nice right now.

 

[torqueman2002]

Continued from post #1, above.

Measurements.



Links to each switch and editors recommendations at end.

All switches are rated:
1/2-HP 125-250 VAC
10A-250 VAC
20A-125 VAC


1442 R | BU04225.0002



1514 R | BU01186.0000

Continued in post #23, below.

 

[torqueman2002]

Continued from post #22, above.

1148 R | BU01186.1000



I tested each switch, first in the flat-top (ftop) Block.
Flat-top Block

1442 R | BU04225.0002
There is a (~1/8") gap, when the PSW is fully seated against the left hand (LH) side of the switch cut-out.


With the PSW centered in the cut-out, there is no noticeable gap.
Outside view.

Inside view.


Continued in post #24, below.

 

[torqueman2002]

Continued from post #23, above.

1514 R | BU01186.0000
There is a (~1/8") gap, when the PSW is fully seated against the left hand (LH) side of the switch cut-out.


With the PSW centered in the cut-out, there is no noticeable gap.
Outside view.

Inside view.


1148 R | BU01186.1000
There is a (~1/8") gap, when the PSW is fully seated against the left hand (LH) side of the switch cut-out.


With the PSW centered in the cut-out, there is no noticeable gap.
Outside view.

Inside view.


Continued on post #25, below.

 

[torqueman2002]

Continued from post #24, above.

Round-top Block

1442 R | BU04225.0002
There is a (~1/8") gap, when the PSW is fully seated against the left hand (LH) side of the switch cut-out.


With the PSW centered in the cut-out, there is no noticeable gap.
Outside view.

Inside view.


1514 R | BU01186.0000
There is a (~1/8") gap, when the PSW is fully seated against the left hand (LH) side of the switch cut-out.


With the PSW centered in the cut-out, there is no noticeable gap.
Outside view.

Inside view.

Continued on post #26, below.

 

[torqueman2002]

Continued from post #25, above.

1148 R | BU01186.1000
There is a (~1/8") gap, when the PSW is fully seated against the left hand (LH) side of the switch cut-out.


With the PSW centered in the cut-out, there is no noticeable gap.
Outside view.

Inside view.


Evaluation - None of the 3 power switches are an exact fit; they are (~1/8") narrower than the tested flat top and round top Block grinders.

With the PSW centered in the cut-out, there is no evident gap.

Each PSW was cycled ON/OFF at least 25 times. All of the PSWs have a firm and positive action. The spring clips that hold the PSW in the cut-out, keep the PSW held in place while cycled ON/OFF 25+ times.

To permanently mount the PSW, use 3-4 dabs of epoxy at the back of the PSW/cut-out interface.

Recommendations
Any of the 3 switches are suitable as 'snap-in' replacements for up to and including 1/2-HP Blocks.

You may want to use 3-4 dabs of epoxy to keep the PSW centered.

Best-Buy
1/4" Spade Terminals
1442 R | BU04225.0002


Editor's-Choice
Screw Terminals
1514 R | BU01186.0000

I like the feel of the switch, it was a bit more positive. Additionally, the screw-on terminals are my preferred motor electrical-connector.

Thanks for looking.

Ordering information.
http://www.partstown.com/

1442 R | BU04225.0002
=================
BU04225.0002
SWITCH, TGL ON/OFF BLK-SPST
$4.10

==================================
1514 R | BU01186.0000
=================
BU01186.0000
SWITCH,ON/OFF TOGGLE-BLK
$4.60

==================================
1148 R | BU01186.1000
=================
BU01186.1000
SWITCH, ON/OFF TOGGLE-BLK 3PK
$13.70
==================================

 

[kenc184]

Just had the switch die on my 1/2HP block. I got this replacement from McMaster, cost about $14, it's motor rated, 16A. Had to file a tad vertically, then needed a small square of sheet metal behind to fill the 1/8" gap horizontally. It's a MUCH nicer feeling switch than that God awful OEM thing.

High-Starting-Current Rocker Switch, Wire Leads, Spst-No, Horizontal Line/Circle

7194K53

 

[Left-tilt]

Maybe I've missed it in these posts or maybe I'm not as sharp as you all. I have several wires to my switch. One I know is the light, no big deal there. But you all are using 2 pole switches? Can someone explain how there are converting from the cheap (broken!) switch to the 2 pole?? I have a 1/2 horse April 1973 model 397.15591. Thanks in advance!!

Did you ever get an answer to this question? I bought the two pole switch from Grainger as recommended but I have several wires to connect. If anyone has a diagram or instructions on making a 3 pole, a two pole, that would be great.

 

[torqueman2002]

Sears sold bench grinders, Blocks included, for many years.

I am not familiar with 1/2 horse model 397.15591; but I have information on several 1/2-HP m-397.19591. It is a dual voltage 115V/230V model, and uses a DPST power switch.

The Block models in this thread are single voltage models - 115V, and use SPST power switches.
...

Left,
What model grinder do you have? Pictures of original wiring & switch would be helpful.

You can use Single Pole Single Throw switch above on a Dual Voltage grinder wired up for 115V, but the grinder cannot be used/wired for 230V.

I have several schematics/diagrams of Block wiring. If you post the model number, I will be able to choose the appropriate one.