Bench Grinder Restoration (Belt driven)

[Greased Throw Out Bearing]

Hello all

I recently found a Grinder in the shape of a yoke. I have no information about it like age or date but I will get some hi resolution photos up here tomorrow. I have experience as an auto mechanic but none as a machinist.

I decided to use this grinder as my first project because of the unique characteristics. But this isn't a precision machine to learn, it was free and it's simple. The perfect learning experiment,

Lead (I assume by the grey color) babbit bearing, no simple press in ball bearings, no sire bob! There are oil cups on top, one of which is broken. All of which I've never used. The arbor shaft has square threads, not even acme threads! My friend and I are debating if we should turn the shaft down and get oversize bearings or turn a completely new shaft (without square threads). The top surface of the base is curved, preventing a bolt from securing down.

The base was pretty uneven so I pulled out my dad's old files. I've already learned to file in one direction, how to position my arms and boy, how to clean files with a file car or piece of brass to clean between the teeth, and even how to pickle files. Already I've learned quite a lot.

 

[Bob Korves]

It is an antique. Treat it like one... Gently.

 

[Greased Throw Out Bearing]

https://goo.gl/photos/XiNAeEayqphXfxQV7

https://goo.gl/photos/aLJ9AmRH65acVuDd8
This is an clear shot of the yoke without the spindle. The only markings I found on it were "C O". I found it in a Chicago lumber mill and wood shop that's over 100 years old. A group of young hip gentlemen have kept it as a business that restores old lumber furniture and building materials. Kudos to them.

https://goo.gl/photos/1nd9RFiei3fgSXhY8

https://goo.gl/photos/UUz5JZJE6NAgMUe49

https://goo.gl/photos/3hoJZ9e5TsqPHNUj9
These shots show the clamps, oil cups, and grey metal bearings. One of the oil cups is missing a spring, maybe I could rig some spring up because I have no idea how to replace this oil cup, there's no threads. The hole for the oil goes right through the lead babbit bushing, which looks terrible.

-I am very confused about the clamps and screws. The grain pattern of the metal appears to be cast, which doesn't have a lot of flex. So why would there be a screw to clamp it downs?​

 

[Greased Throw Out Bearing]

https://goo.gl/photos/8JoAGrdM76y3QBK76 This is the 10 1/2 inch arbor shaft. You can see it's square threads https://goo.gl/photos/QxYYbYLCjchC8WHg7 I'm not sure if I should turn down the shaft or turn a completely new shaft (with conventional threading).https://goo.gl/photos/rcA6259hSCFc3xQz8 You can see the pitting and scratches from the bushing that needs replacement.

You can see this is where the washer and bolt would sit. https://goo.gl/photos/bTjUhEQ2fGXsFoTt8 It's not really a flat surface. The yoke is directly above the hole otherwise I'd put it under the drill press with an abrasive or stone disk to grind it smooth. I can't think of anything other than using a copper washer.

Here's the base https://goo.gl/photos/3yTibSksnWWuy8aL9 I have started working on it. Initially, the casting was so uneven that the base would actually rock on a flat surface. My welder friend advised me to put it in a vise and file it.

Now my father left me with an extensive set of files, but I didn't know anything about files. I found Nichol's "File Filosophy" http://www.wewilliams.net/docs/1920 - File Filosophy by Nicholson File Co.- 11th Ed.pdf Cut on the forward stroke, position my body, arm and hands in a perpendicular position to the work piece. I cleaned my files with a weak acid, a brush, and scrap piece of brass. Man can they cut now! I even sought out advice how to file this wishbone shape, and I followed a pattern to flatten out the piece.

I wonder how flat should the bottom be. The base is about 3/8 inch thick. The deepest casting imperfection is 1/4 of an inch into the base. The base no longer rocks and, the top of the yokes where the arbor sits appears level in both directions.


*I tried uploading images but that didn't work so I linked them. They're worth seeing, I took them with a good Canon SLR.

 

[dlane]

Bunches of red x's , probably a good grinder though.

 

[Greased Throw Out Bearing]

Hey I've links to everything but I tried uploading the photos with no luck. I'm using google photos. Do you know how to upload them?

 

[tweinke]

That is certainly an old piece! A nice restoration would be in order if it were mine. Even if it sat on a shelf when done. I did follow the links you provided, its too bad its kind of a pain to get photos on here until you get the hang of it which I have not accomplished successfully either.

 

[Cavediver]

I wonder how flat should the bottom be. The base is about 3/8 inch thick. The deepest casting imperfection is 1/4 of an inch into the base. The base no longer rocks and, the top of the yokes where the arbor sits appears level in both directions.

I would vote for "flat enough not to rock" and call it good. Preserve the original casting character.
Have you considered re-pouring the babbit? That would be a neat experience! For a piece that size you wouldn't need serious hardware; a propane or mapp torch and a small steel pot or small casting ladle would do the trick.

 

[Greased Throw Out Bearing]

Cavadiver, I never realized that babbit was poured in! I certainly can gather all of the material i don't yet have, babbit ingot, cleaning solvent, clay to plug the bottom and optional tin and flux.

How would I align the shaft in the yoke? I could try to do it one bushing at a time and use one of the old bushings to hold the new one. However, the bushings are extremely worn out. On each bushing, the inside of the yoke is intact https://goo.gl/photos/1nd9RFiei3fgSXhY8 while the outside by the grinding wheel is worn https://goo.gl/photos/3hoJZ9e5TsqPHNUj9

 

[Rockytime]

Pix came out fine on Google photo. Anxious to see how this works out. Crossing my fingers for a great finish!