Grinding wheels and HSS

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MikeC
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Post by MikeC »

Interesting about the lack of a rest. I use my big 10" grinder with the rest, as DOM says, to avoid getting hung up in the guard. The other day I was grinding a quick lathe tool, so I roughed it in on the big grinder and then looked over my shoulder at the T&C grinder sitting back there with a narrow sharp wheel on it. It is indeed pretty handy! I think I'll probably still rough out on that big 1750rpm pedestal grinder, but I'll definitely save a couple of special rocks for the cutter grinder to final finish and shape.
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Harold_V
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Post by Harold_V »

MikeC wrote:I roughed it in on the big grinder and then looked over my shoulder at the T&C grinder sitting back there with a narrow sharp wheel on it. It is indeed pretty handy! I think I'll probably still rough out on that big 1750rpm pedestal grinder, but I'll definitely save a couple of special rocks for the cutter grinder to final finish and shape.
You've grasped the point I've tried to make. A grinder with a rest is too restrictive for many of the operations that make for a better cutting tool. How you arrive at the basic tool should be done with the most comfort and confidence of the workman, and need not be done as I do mine.

Adapting to the system I use didn't come easily at first-----but as you're observation of those special rocks suggest, you get to the point where you benefit greatly by getting away from convention. It's not for everyone----some folks will never master the art of grinding tools by hand-----let alone learning to do so without a rest. However., for those that accept the challenge, mastering the process is a major step forward.

What's important is for each individual to understand the process, whether it's adopted or not. That way, when a complex grind is a necessity, you have a sense of direction in how to accomplish the task.

Harold
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BadDog
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Post by BadDog »

Speaking earlier of using "cluster diamonds", is THIS something that would be useful in that capacity? I've also seen the "cluster" diamonds where there were several distinct diamonds, but then I ran across this with a similar designation and wondered how it would work. Would this be more akin to the Norbide sticks in that it would provide a smoother dress that will be hotter, but provide a nicer finish?
Russ
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Marty_Escarcega
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Post by Marty_Escarcega »

Well, just ordered my grinding wheel, dressing stick and dual shaft motor should be here later this week. Then I get to build an arbor.

Question though for Harold. Your arbor calls for 2-3/4" flange built onto the arbor. In order to save time and material, could one start with a 2" piece of stock turn a shoulder and use 2.25" dia. x 5/16 thick washers?
Or weld on a piece of metal then turn/face the flange?

Harold, I know you were specific about the flange diameter. Just asking if there may be an alternative to buying or scrounging 3" stock.

Thanks again Harold. I've yet to decide what sort of wheel to put on the other side.

Marty
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Harold_V
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Post by Harold_V »

Marty_Escarcega wrote:Question though for Harold. Your arbor calls for 2-3/4" flange built onto the arbor. In order to save time and material, could one start with a 2" piece of stock turn a shoulder and use 2.25" dia. x 5/16 thick washers?
Or weld on a piece of metal then turn/face the flange?

Harold, I know you were specific about the flange diameter. Just asking if there may be an alternative to buying or scrounging 3" stock.
Certainly, pretty much any combination of things could work--but remember that you'll be working directly in front of a wheel that is all too capable of killing you. The large flange size is in keeping with proper flange support of the wheel----I would not recommend a reduction, although you'd be pleasantly surprised to find a flat washer under a nut would work, too. I just wouldn't want to stand in front of it. The whole idea is to promote as much safety as is possible. The large flange diameter supports the wheel properly for those times when you have to use the side of the wheel, which is often.

The advantage of making the adapter in one piece is that you have maximum rigidity and alignment. There's no reason why you couldn't turn the adapter, sans the fixed flange, from a small diameter piece of stock, providing a shoulder for what would have been the fixed flange to locate properly. The flanges would then be made from flat stock, even torch cut before machining. If you did your work well, it would serve equally as well as the one piece method I suggested. Making the flanges without soft jaws could prove challenging---but not impossible.

Welding is another possibility, but I'd do that only if I was very good at welding and knew that taking cleanup cuts to keep the adapter as well balanced as possible wouldn't challenge its integrity. It is not a choice I'd make for myself, but I have a generous supply of large diameter material, and a lathe that can reduce the stock @ ½" per pass at high speed, so I see things somewhat differently.
Thanks again Harold. I've yet to decide what sort of wheel to put on the other side.
Marty
There is likely no hurry. You may come to realize that you can use brazed carbide to advantage in the future, and can add a diamond wheel to the grinder if you do. You may also decide on a rough and finish wheel, or even a hard wheel for general use. With the second side available, you have a lot of options.

Good luck, Marty. Keep the board advised of your progress when you get started. It's always interesting to see how these projects unfold.

Harold
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Post by Marty_Escarcega »

Harold, I should have mentioned the washers I was looking at are actually machined washers, not the stamped variety, machined to tolerance. Though they were only 2.25" in diameter. I could machine the relief as called out in your drawing.

How much of the front of the wheel do you feel is reasonable to be exposed? (I will make gaurds, along with a side cover).

Hmm, perhaps I will try and take pictures along the way......

Marty
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Harold_V
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Post by Harold_V »

Marty_Escarcega wrote:How much of the front of the wheel do you feel is reasonable to be exposed? (I will make gaurds, along with a side cover).
I just gave mine a visual---and found it to be approximately 120° of opening, 60° above center and 60° below center. It's important to have a generous amount of the wheel exposed so you can manipulate the tool when grinding chip breakers. Keep that in mind when you make the side covers, too. If they get in the way, you defeat the purpose of the grinder.

While I don't promote the idea, I have no cover on the outside of my grinder for that reason.

No, it's not safe.

Harold
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millman5
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HSS grinding

Post by millman5 »

Firstest & mostest!!!!! THANKS Harold. I have been grinding my own HSS for years, most of it a good grade US M-42. I agree that free handing them, once learned is best.

I have used many different manufacturers of Al. Oxide wheels. Everything form USA to Imports with widely varied success. After reading your post on grades, I went out to my "wheel storage cabinet" & dug out an old Norton wheel I've saved back for several years. It was an 8" wheel that was wore to about 7.125" My grinder being 7" I decided to try it. I gave it the ring test, & mounted it. Of course it had been well rounded on the corners. Once properly dressed I started to grind some of my shaper bits.

HOLY COW, WOW, I CAN"T BELIEVE IT!!!!!!!! The performance of the correct grade wheel is astounding to say the least.

I usually man 1 section of my shop which is dedicated to making the parts shown in the attached pic. I most usually keep My VTL & (3) 24" shapers running at the same time for these. I mill the taper on the back side of these parts on the shapers. .200" depth of cut & .040 feed per stroke. You can imagine how much tool grinding there is per day.

I feel so stupid for not researching this before. I've always known there are different grades for different jobs. I've purchased them for valve grinders & tool post grinders. When It came to a standard bench grinder I've just purchased standard bench grinder stones!!!!

AGAIN THANKS!!!!
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Harold_V
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Re: HSS grinding

Post by Harold_V »

millman5 wrote:Firstest & mostest!!!!! THANKS Harold.
;-)

Harold
steam4ian
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Post by steam4ian »

G'day Harold et al

Just read Harold's opening post, a revelation as to why I am recently finding tool grinding less than easy. Out there and reface the wheel. Thanks Harold.

On the other hand I have had some success with an (ouch!) angle grinder. You hold the tool blank in the vise. Good for roughing out with the final grind on the wheel then finish on an oil stone.

Regards
Ian
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Harold_V
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Post by Harold_V »

steam4ian wrote:G'day Harold et al

Just read Harold's opening post, a revelation as to why I am recently finding tool grinding less than easy. Out there and reface the wheel. Thanks Harold.
Welcome!

Please do pay attention to the wheel hardness, too. If you have to bear down on HSS to accomplish the grind, the wheel is likely too hard.

Welcome to the forum.

Harold
knudsen
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Re: Grinding wheels and HSS

Post by knudsen »

Is there any special technique to bring an out of round wheel back to life? I inherited an old Craftsman grinder from the early 70's and I have the original wheels with it. Wheels were pretty rough, clogged, rounded corners and the course had a "V" in the center. Probably my father's son messed them up when he was a kid :oops: Bought a couple of Weiler wheels locally for it, but don't like those at all. They are going back to the store to kill someone else. Dang things have a stack of plastic arbor size adapters and have to use them all to get down to 1/2" and it's sloppy. So I remounted the old Craftsman wheels and hit them with a dressing stick, the type described at the beginning of this thread. They are in a lot better shape now, but the coarse one is still out of round. Do I need to just keep grinding more off? They say type "N", if that matters to the fix. I've got a star type dresser somewhere if I can find it, maybe I need to use that? Or a diamond?
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