Grinding rock

[threeputt]

I just noticed today that for the last 30 years I have been using a 6 inch grinding rock on a 7 bench inch grinder. Is this something I need to change ? It has worked great all these years. Nobody around my parts stocks the 7 inch rock and that's why I probably changed it way back when and didn't pay attention.

 

[larry4406]

I would think that your 30 years of service has proven it works and leave well enough alone.

 

[seber]

You can use a wheel down to as small as you can stand it but the bigger diameter will grind faster. It will also produce more heat.

 

[threeputt]

I was planning on using that one. Back when I installed it I probably didn't know about this being a 7 inch grinder. Long time ago for sure when I installed it.

The other old ( 1964 ) craftsman I bought a few months ago needs a rock and only 6 inch ones are available around here.
The one I just bought ( 7 inch ) passed the ring test but someone that had this grinder before me used the side of the rock for grinding and I am told that could damage it. I found a 7 inch X 1 Forney online but I know it's made in China. Not sure which one would be the safest ?

 

[neophyte]

The major issue with using a smaller wheel than the bench grinder is made for, is that there is extra space around the wheel in the blade guard, which can make it easier for stuff(clothing, tool bits, whatever) to accidentally get pulled in between the wheel and the guard, which can cause safety issues.
A smaller wheel also might wind up further away from the tool rest, leaving a wider gap between the tool rest and wheel, making it harder to grind/sharpen stuff, and again making the grinder less safe, although this might not be as much of an issue depending on the tool rest design, and how adjustable it is.
Lastly, a wider space between a wheel and the wheel guard leaves more space for stuff caught between the wheel guard and wheel to accelerate, and makes it easier for that stuff to get flung out towards a user. This could also be an issue if the wheel fractures in use.

 

[threeputt]

You think its ok using the 7 inch old rock being someone looked like they used the side to grind with ? Not terrible but definitely not smooth like the other side of it. Other than that it looks ok and does pass the ring test. The rock is a Craftsman and might even be the original. I am going to bring that grinder home to use on occasion because most of the time I am at my shop 5 miles away.

 

[neophyte]

If the side was used for grinding, it really depends how much.
Most users probably grind on the side occasionally, and some of the thin vitrified wheels used for sharpening chainsaw blades, are also used on equipment for sharpening circular saw blades, which means side grinding, so a bit of side grinding on a thicker wheel isn’t going to be an issue.
Just stand to the side as you turn the grinder on, to make sure you’re not in the way if s wheel fractures.

 

[kelpaso1]

Uhh, it's called a grinding WHEEL not a rock. Never heard of that term.

 

[Tools4Me]

You think its ok using the 7 inch old rock being someone looked like they used the side to grind with ? Not terrible but definitely not smooth like the other side of it. Other than that it looks ok and does pass the ring test. The rock is a Craftsman and might even be the original. I am going to bring that grinder home to use on occasion because most of the time I am at my shop 5 miles away.

Some of the older drill bit sharpening jigs used the side of the grinding wheel for drill bit sharpening. That might be why the side has wear on yours. I say it's fine as long as the wear is shallow and doesn't affect the overall balance/vibration of the wheel when its' spinning. If your wheel passes the ring test I say use it. I use older wheels that I come across at garage sales whenever possible. As long as they pass the ring test they shouldn't break apart on you during use. Some of the older wheels actually last longer and require dressing less often than the newer stuff.

The only other consideration I can think of, would be as your grinding wheel wears down the side groove in the wheel will eventually become the leading edge corner of the wheel. When that happens, you won't be able to have a really nice sharp right angle on your wheel's edge unless you also dress the side of the wheel or grind your way through that section of the wheel. Not a big deal usually, but it might matter to some depending on what the grinder is used for.

 

[gnpenning]

Grinding wheels wear down with use, that is one reason why tool rests are adjustable.

 

[Walkers]

Wheel or stone is accept, rock is not.

 

[threeputt]

Here is close up of the wheel in question. I ordered a new one . Even though it passed the ring test I don't trust it. This one is going to the scrap. I have worked in a shop for way over 50 years and would like to make it a few more without serious injury.
Also I have a grinder that has been in my shop for ages just like this one and never had a tool rest on it. I took the tool rest off the wire brush side on this one and put it on my other. Never going to ever use a tool rest on a wire wheel side after what happened to me the first of the year.

 

[seber]

Along with the tool rest, you might want to remove the outer cover. I wire it to the back of the stand so it stays with the grinder.

 

[threeputt]

Good idea on where to put it. I had already removed it because of the injury got in January. Here is how it was when I bought it. I was in a hurry one day and just had to turn it on for a second instead of walking to the other side of my shop to use my other one . My other one has been removed for 50 years .