Surface Grind 101

I have found that the cheapest no name import wheels are not worth a damn. Out of balance, wobble, tend to burn the metal, just awful. Sometimes used wheels can also be out of balance from coolant settling down to one side and then drying there. If you are using coolant, let the spindle run for a few minutes after stopping the coolant to let it get thrown out of the wheel.
 
"The first wheel I bought for my SG was one that would serve as a general purpose wheel and also be a good selection for dusting my magnetic chuck. I decided on a 32A46-HVBE from Norton. "

And your go-to, medium and fine grinding wheels of choice? Or, can you use this wheel for multiple applications?
I assume 7" x 1/2" on all?
Thank you!

I only use the one grit - 46. If I want a finer finish I will dress the wheel finer, take lighter cuts, use oil on the surface and a smaller feed rate across the surface. I have another wheel besides the above which is a Norton 38A46I8VBE and the only reason I have that is because I got it new when I bought my SG.

For my hobby work, the only reason I can see buying another wheel would be if I wanted to grind into a sharp corner or maybe needed to grind a radius. Then, a harder wheel would hold up better especially in the corners. I do have some worn Norton cup wheels that I plan on using for side grinding. They were discards at a place where I used to work, but will work well for side grinding on a SG (for my use anyways).

As I learn more, I might change my mind, but currently, the one wheel works fine for all my uses. Using the variables I mentioned above can get you very different results.

I actually think proper dressing is more important than wheel selection, but others with more experience might feel differently.

Ted
 
I have found that the cheapest no name import wheels are not worth a damn. Out of balance, wobble, tend to burn the metal, just awful. Sometimes used wheels can also be out of balance from coolant settling down to one side and then drying there. If you are using coolant, let the spindle run for a few minutes after stopping the coolant to let it get thrown out of the wheel.

Yep . And when you start the wheel up , start the rotation of the wheel with your finger . The torque of the machine will sometimes throw the wheel out of balance . ( this is not a beginners practice , so take caution )
 
Wow, 36 grit. You would think that would leave a rough surface.
Coarse wheels do not get filled up with swarf so easily. A really fine wheel fills up quickly, and then the swarf ruins the finish. With a coarse wheel and looking for a good surface finish, slow down the traverse and cross feed table feeds and speeds somewhat so the coarse grit has a chance to find all of the surface. The finish can be very good.
 
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Not to hijack the thread I think it’s relevant. How does one store their wheels? Mounted and unmounted?
Lay flat ,upright, peg board?
I have a decent amount of wheels new and used and right now I lay the unmounted flat. I have about six wheels mounted on hubs and I stand those upright. I don’t like it.
I’ve been pondering what type of storage to make for the wheels to keep them together and preferably something hanging on the wall. Now their just stacked in the grinders base cabinet and I don’t like that either. If something goes wrong with the coolant tank they’re in the line of fire.
Was thinking maybe a 8x6 box like 3’ tall. Shelves every 8” and adjustable and maybe make triangle horizontals pcs. to cup the radius of wheel so they don’t rock. Then maybe put a plexi glass door to keep it semi sealed? What do you guys do?
 
I hang the wheels on a peg board by size and grit just like we did at work.. In total there are about 3 dozen wheels with many of them being multiples of the same grit and hardness. When hanging several wheels on one peg I put a piece of cardboard between them to keep them from banging into one another. Categorizing them with the labels in plain view makes it easier to find the correct one.

As for hubs I currently have only 1. It's an older Sopko without any internal balancing weights. Mine is a 7" machine and I've never had any trouble with wheel balance. Whenever I need to change wheels I leave the hub attached to the spindle and just replace the wheel. A quick dressing and on to the work.

As an FYI I always warm up the machine by leaving it run for a minimum of 10 minutes before starting to grind. This helps normalize the bearing temperatures and insure there will be no change in surface finish from the start of a job to the finish.
 
I have off today so I have some time in the garage. Just a example of grit and finish. Here’s some pics of a v block I’ve been doing. 46grit aluminum oxide. Don’t know if it’s right but that’s what I picked. First pic is manufacturer finish second and third are my finish.
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6C6372BF-ED97-43B2-AF17-4CC8F86CE3F7.jpeg13E2D237-7A91-4611-8BE5-C62978EF3466.jpeg
All three taken with zoom on iPhone. Kind of hard to get the look but my finish has more of a reflective,polished look. Fingerprints make it look bad. Kind of funny looking at the pictures how grainy they all look but yet you don’t see that unless magnified. Smooth as glass.
 
Not to hijack the thread I think it’s relevant. How does one store their wheels? Mounted and unmounted?
Lay flat ,upright, peg board?
I recently made 2 wall mounting boards for my grinding wheels out of plywood I had laying around and hung them behind my surface grinder. I put hardwood dowels covered with clear shrink tubing into holes drilled 7 degrees upward from horizontal to match the adapter taper and to help keep them from falling off. I put screws into the dowels from the back side of the boards to expand the dowels tightly into the plywood. The racks are hung with some galvanized sheet steel I had laying around. Zero money was spent on the project. Designed to use what I had on hand.

5 of the wheels on the rack have adapters mounted to them, they are my "go to" wheels for the time being. I have three more loose adapters I can use on wheels I think I will use much less often, can dress them round after mounting for each use, if and when needed. Seemed like the best solution for now without blowing the budget on wheel adapters. Overflow wheels, unmounted adapters, and other surface grinder accessories are kept in the carbide grinder stand that is opposite the surface grinder controls.

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Looks great Bob!
How do you center the adapters on the wheels?
Isn't there 1/8" adjustment?
 
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