Diamond wheel tool grinder

IIRC the used Baldor tool grinders I've examined generally had a well- worn carbide face wheel on the right side and less-used diamond on the left. I don't recall aluminum wheels on any but freehand grinders, again with the coarse wheel on the right and fine Al or SiC on the left. I was never willing to bid anywhere near the price the tool grinders went for.

I don't want to argue with Harold and/or Susan, but using the SiC wheel to lightly polish HSS and carefully finish wood tools hasn't seemed to injure it for carbide lathe bits.

Jim Wilkins

What's that Lassie? You say that Doug White fell down the old rec.crafts.metalworking mine and will die if we don't mount a rescue by Wed, 22 Oct 2008 00:15:57 GMT:

We have one of those at work. I use it to make custom tooling from standard brazed carbide inserts. I also use it to turn standard inserts into wiper inserts. They are expensive, but worth it for a job shop.

rounded quickly,

How can this wheel be repaired? Any easy way? Even possible? phil

Resinoid bonded diamond wheels are commonly dressed with aluminum oxide dressing sticks. They're quite fine, something like 180 grit, and are generally large. You're likely to find one that's one inch square and six inches long. I've seen them white in color, and also black, which I suspect is made of silicon carbide. Do a search for dressing sticks for diamond wheels. Major machine shop supply houses sell them.

They restore the wheel readily, but you lose a little of the wheel in the process. Use it sparingly, and avoid grinding steel so you get maximum life from the wheel. A small portion of the bonding agent is removed, freeing the dulled diamond bits and exposing new ones. There is little you can do to restore the dulled diamond bits aside from removing them.

A decent wheel, 100% concentration and 1/8" thickness should last a person for a life-time, assuming it's used in the hobby shop. They last several years when worked commercially, assuming they're well cared for.

Harold

Jim Wilkins

It isn't a matter of injuring the wheel. It can be dressed to restore it's cutting capabilities. It's a matter of understanding that the wheel is not cutting properly. Said another way, it's bad practice. On the other hand, it's your wheel and your material -----so if you feel it's serving a purpose that couldn't be better served by applying what is considered better practice, by all means continue the course.

My purpose in commenting is to alert readers that silicon carbide wheels are not advised for steel. They perform poorly when so applied, but if you don't know the first thing about grinding, you likely don't understand they're not working properly.

Were you to apply the wheel to carbon steel, it would border on the impossible to keep the wheel from drawing the hardness. You're fortunate to be grinding on HSS, which is difficult to anneal.

I still don't recommend the process.

Harold

possible?

aluminum oxide

grit, and are

inch square and six

black, which I suspect

sticks for diamond

the wheel in the

you get maximum life

removed, freeing

little you can do

them.

should last a person

They last several

cared for.

Thanks Harold. I have one of these sticks and was wondering if they were really the right thing to use. I've caught visitors grinding their pocket knives on it while I was welding something for them. Spank spank! Grrrrr.... phil

I can grind a plane blade or wood chisel on it, just to finish the edge after shaping them on the A36 wheel, without burning. Maybe it works because I grind steel on SiC so rarely, lightly and briefly and the usual carbide lathe bits maintain its condition.

If I had the space for another grinder I wouldn't do it. This grinder is IN the doorway to the shop, pushed back against the door frame.

Jim Wilkins

I can grind a plane blade or wood chisel on it, just to finish the edge after shaping them on the A36 wheel, without burning. Maybe it works because I grind steel on SiC so rarely, lightly and briefly and the usual carbide lathe bits maintain its condition.

***That's entirely possible. If you use it very briefly, it will act more as a burnishing tool than a grinder. The surface finish will not be ragged because it doesn't cut well. The dulling comes almost instantly----very evident if you're trying a cut on a surface grinder, for example. If you can keep the heat down, I sure as hell don't see a lot wrong with the operation. I commend you for your ability----it's not easy even with an aluminum oxide wheel. If it ain't broke, don't fix it.

Harold

I always pick up mine with trepidation, knowing full well it's taking life out of the wheel.

Contrary to what you might expect, the diamond wheel cuts the dressing stick quite rapidly. After all, it is diamond. It takes only a brief encounter to restore the wheel surface, so go sparingly and use light pressure, and try to present a broad surface to the wheel to avoid cutting a groove.

Once you've used it, you can clearly see the benefit. The ability of the wheel to perform undergoes a shocking transformation. Just rein in your desires to do it often. Run coolant and keep the wheel surface clean and free of contact with steel and you don't have to. A loaded wheel is no better than a dull one.

Harold

wondering

it's taking life

the dressing stick

brief encounter to

pressure, and try

groove.

The ability of the

Just rein in your

surface clean and

loaded wheel is no

Oh man, good thing you weren't here yesterday when I 'cleaned' mine, you would've kicked my butt! harhar.... I'll go more lightly next time, eih? I'm old but I can still learn this. I'll be 62 next April and retired then. Gonna still chase this hobby though, so much fun!! phil

Come to think about it, Drill Doctor uses a diamond wheel quite successfully. Gerry :-)} London, Canada

Chuckle!

Old, eh? I've been retired since '94, albeit at an early age. I'm 69 now and feel every damned one of those years.

Harold

Actually, the wheel in Drill Doctor is not diamond, I believe that it is CBN (Carbon Boron Nitride). The reason is exactly what Harold stated.

I do, however, have a diamond manual knife sharpener that works beautifully, I owned it for many years. The difference is that it is a slow speed, manual process, without heat.

Somehow I got the impression it was diamond, probably from the discussion here several years back when they were first introduced. Whatever it is, I am quite happy with mine.

I have several diamond plate sharpeners that I haven't used all that much - too much time on the computer, not enough time being creative. At least that's what SWMBO says. Gerry :-)} London, Canada

Copy cat! You're my twin 9 May '39 Gerry :-)} London, Canada

I am very happy with mine, that is, since I understood how to use it.

She might mean by that something other than pulling the knife back and forth on the sharpening stone.

The hell you say! July 14 for me.

How you holding up, Gerry?

Harold

Well, you're 11 yrs. older than me, but almost 20 younger than Dad. He's finally slowing down. Transient ischemic attacks are blowing little chunks of memory, but he still gets outside to cut limbs, kill weeds, and mow.

Pete Keillor

I'm only as old as I feel, so I only count every other birthday. Next year, Junior (born 10 10 74) and I will be the same age! Seriously, I am thoroughly enjoying second childhood - don't know how I ever found time to earn a living. SWMBO and I just celebrated 46 years of living our separate lives together. Gerry :-)} London, Canada