View Full Version : Grinder modification idea.

J Tiers
03-01-2017, 11:03 PM
I have a Baldor grinder that I bought for $5 at a sale. I also have a bunch of wheels, including some metal backed ones, probably but not surely green carbide. I had the idea of putting a side table on it, similar to the typical "carbide grinder".

Problem is, that with the standard setup, that leads to a long "nose" sticking out, that makes it somewhat non-useful and problematic to use with a side table.

http://img.photobucket.com/albums/0803/jstanley/machines/baldor/IMG_3961_zpsxtb3aw85.jpg (http://smg.photobucket.com/user/jstanley/media/machines/baldor/IMG_3961_zpsxtb3aw85.jpg.html)

I could modify the shaft, by cutting it off and re-threading it at a shorter length. That would be a one-way street.

Or, I could add a section between the motor body and the wheel guard, to bring the wheel and guard out about one inch, which would bring the nut to a better place relative to the wheel, etc.

OK, that adds "stickout" to the shaft, but in reality, not much more than the nut thickness, since you can put a wheel on it now that fills up the entire space and needs no outside spacer. When I got the thing it had a really wide recessed wheel on it that prompted the owner to remove the outer guard, and probably got used as a side-grinding wheel. Picture below.

Adding a spacer does not seem any worse than the pic, as far as added propensity to go into a "whip" mode.

http://img.photobucket.com/albums/0803/jstanley/machines/baldor/newBaldor_zpse17a86e1.jpg (http://smg.photobucket.com/user/jstanley/media/machines/baldor/newBaldor_zpse17a86e1.jpg.html)

Plus, the existing shaft would need a larger sleeve on it to provide the driving recess for the inside flange, and that sleeve when the nut is tightened, will give added support to the shaft. As-built, there is a sleeve with a recess, but that would be well inboard of the wheel guard after a spacer was added.

Any thoughts?

03-01-2017, 11:37 PM
I made one using a table from a old disk sander with a 3450 RPM motor. Made a hub for the diamond wheel, and wired a reversing switch in and made brake for it


03-01-2017, 11:42 PM
The wheel guard is outside of the outer bearing? If so then it would be an option to space it out as you say.

You would likely need to make up new inner flanges for the wheels. Something with a top hat like shape to let the stub sit against the shoulder and long enough to move the flange out so it mounts the wheels where you want. That's likely a positive thing though because with a nice precise fit, maybe even a light press fit, it will ensure the flange face runs nice and true.

There would be more overhang so wheel balance would be a more important factor. Out of balance wheels might tend to get the shaft whipping a little. But if balanced well there shouldn't be any issue.

And best of all as you say it's totally restorable.. with a touch of help with a pulley puller depending on the fit of the new top hat style flange.

J Tiers
03-02-2017, 12:32 AM
So I made the adaptor....

http://img.photobucket.com/albums/0803/jstanley/machines/baldor/IMG_3963_zpsyhgzknjp.jpg (http://smg.photobucket.com/user/jstanley/media/machines/baldor/IMG_3963_zpsyhgzknjp.jpg.html)
http://img.photobucket.com/albums/0803/jstanley/machines/baldor/IMG_3964_zpst0ja5czv.jpg (http://smg.photobucket.com/user/jstanley/media/machines/baldor/IMG_3964_zpst0ja5czv.jpg.html)

It has to fit against the motor housing and the wheel guard just as those two fit each other.

Here you can see the end of the motor housing, and also the drive recess on the existing sleeve, with the drive stud on the wheel flange.

http://img.photobucket.com/albums/0803/jstanley/machines/baldor/IMG_3965_zpsaapweuuq.jpg (http://smg.photobucket.com/user/jstanley/media/machines/baldor/IMG_3965_zpsaapweuuq.jpg.html)

The wheel guard is set up like this to fit into the motor housing, so I just duplicated the two sets of features.

http://img.photobucket.com/albums/0803/jstanley/machines/baldor/IMG_3966_zpsviigaesr.jpg (http://smg.photobucket.com/user/jstanley/media/machines/baldor/IMG_3966_zpsviigaesr.jpg.html)

J Tiers
03-02-2017, 12:32 AM
And fitted together. Should look good if painted. I still have to make the extension sleeve to fit the wheel flange with drive stud. The wheels I have do not have 4 mount holes, they have a center hole to fit the grinder shaft, and are otherwise driven by the flanges.

http://img.photobucket.com/albums/0803/jstanley/machines/baldor/IMG_3962_zpsqt7f9ocr.jpg (http://smg.photobucket.com/user/jstanley/media/machines/baldor/IMG_3962_zpsqt7f9ocr.jpg.html)

03-02-2017, 01:03 AM
I suppose you could stick an additional bearing in the spacer to help, just a thought but the job looks a good un, proof will be to see how it runs, provided the shaft is stiff enough ( I know an age old, or old age problem) then vibration should be manageable with a dressed wheel.
I think it's a good idea myself. Nicely done

Tundra Twin Track
03-02-2017, 01:15 AM
What HP is that grinder

J Tiers
03-02-2017, 02:01 AM
I'd have to look at the data plate. Maybe 1/3 or 1/2 HP, it has a 5/8" shaft, IIRC, so probably 1/2 HP.

03-02-2017, 07:11 AM
Nice job on the adapter, that should work just fine. That looks similar (but older) to my 1/2 hp Baldor with 5/8" shaft. Its a workhorse.

http://i1277.photobucket.com/albums/y493/ndnchf/Baldor%20Grinder/Bd2_zpsl5mfylmp.jpg (http://s1277.photobucket.com/user/ndnchf/media/Baldor%20Grinder/Bd2_zpsl5mfylmp.jpg.html)

J Tiers
03-02-2017, 11:35 AM
Mine is in fact 1/2 HP.

I do not really need it as a carbide grinder, I plan to get it an aluminum oxide plate wheel, for use sharpening HSS tools, large drills and other uses that are less convenient to do on a curved surface. I already have another similar (non Baldor) plain wheel grinder for general use, as well as a disk/belt sander.

J Tiers
03-05-2017, 12:07 AM
The remaining parts needed to make the grinder modification solid and able to run the wheel. It runs with almost no vibration. Smooth and nice. Now I need to make a table for it.

Leftmost: Adapter bushing from 5/8 to the ID of the wheel plate hole.

Top: Drive extender bushing, fits recess in the drive bushing, and accepts lug on wheel flange It really needs to be kissed off with a surface grinder on the side that has the tab. There is a tiny wheel wiggle that I am pretty sure is due to a couple thou variation on the milling of the tab.

Bottom right: The other wheel flange. It only came with one, apparently the P.O. lost both the wheel guard cover and the outer flange when he put that big fat wheel on it.

http://img.photobucket.com/albums/0803/jstanley/machines/baldor/IMG_3970_zpsyduf0itz.jpg (http://smg.photobucket.com/user/jstanley/media/machines/baldor/IMG_3970_zpsyduf0itz.jpg.html)