Fastest way to dress a wheel from 1" down to 1/4" for slot

I have a 1" wide A.O. 46 grit H wheel and I want to be able to grind a 1/4" wide rectangular slot, reaching down say 1/4-1/2 deep, in a part. What is the best/fastest way to dress this profile into the wheel I have? Is it best to put it on the front, back, or middle of the wheel or does it matter?

I have seen dressing fixtures that dress from both sides of a wheel towards the center, but I am not clear on what kind of dressing tool I would put in them or how to use it. Also most I have seen don't open to 1" wide to start...

-Tom

I don't think it will matter , whatever side of the wheel is convenient. One of these will make short work out of it, these are great if you do this often.

Narrow Wheel Dresser - NWD - Hermann Schmidt Precision Workholding

RJT said:

One of these will make short work out of it, these are great if you do this often.
Narrow Wheel Dresser - NWD - Hermann Schmidt Precision Workholding

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That is a neat tool! I have a couple of unused cluster diamond dressers sitting around, so one of these days I'll make myself one of these with a couple of shielded bearings and bevel gears from the box of bits.

I'd buy the proper wheel.

Big B said:

I'd buy the proper wheel.

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I'm in this category. Why destroy a wheel when you can just buy one?

AARONT said:

I'm in this category. Why destroy a wheel when you can just buy one?

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Thanks for the pointer to the NWD, that is nice!

As for why not buy the proper wheel? Despite my best efforts I have been unable to find the proper wheel that I can afford. My grinder uses 2" arbor hole wheels. I have been able to find 10" X 1" X 2" wheels for reasonable prices ($35) and off the shelf. The closest I have come to getting a 10" X 1/4" X 2" wheel is I have a quote for a special order of a minimum of 8 wheels at $45. They will take 16 weeks.

I'd be happy to purchase, say 2 at $45, if you have them sitting on your shelf. :-)

-Tom

An easy way to change the wheel bore or OD is to cut it on a water jet cutter. I often make small wheels out of sections of bigger broken wheels or make a large bore on a standard 6" wheel. If you do not have a water jet cutter the cost for cutting one wheel should be much lower than a cost of custom one.

Wlodek said:

An easy way to change the wheel bore or OD is to cut it on a water jet cutter. I often make small wheels out of sections of bigger broken wheels or make a large bore on a standard 6" wheel. If you do not have a water jet cutter the cost for cutting one wheel should be much lower than a cost of custom one.

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Grinding wheel manufacturers are really good at producing balanced wheels. So much so that a friend who runs a precision grinding shop almost never needs to balance wheels anymore. If you cut the center hole slightly off perfect center the wheel will be unbalanced. How do you insure you are dead center on an existing hole with the water jet?

tome9999 said:

... If you cut the center hole slightly off perfect center the wheel will be unbalanced. How do you insure you are dead center on an existing hole with the water jet?

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You dress/true the damn wheel.

Hazzert said:

You dress/true the damn wheel.

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And so we come full circle...Because I can’t find wheels that keep me from having to dress/true the damn wheel, I should buy the right size wheel with the wrong size hole and cut them on a water jet and then just dress/true the damn wheel. Ok, got it.

So wise in the ways of science: YouTube

Anything over 6” should be dressed when installed anyways so this shouldn’t be a foreign concept to you.

I’m not the one who suggested cutting the wheel on the water jet but it isn’t rocket surgery to figure out how one gets the spindle bore on center.

Hazzert said:

Anything over 6” should be dressed when installed anyways so this shouldn’t be a foreign concept to you.
I’m not the one who suggested cutting the wheel on the water jet but it isn’t rocket surgery to figure out how one gets the spindle bore on center.

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I dress every new wheel installed, and once mounted on the wheel adapter I balance it and the wheel stays on the same adapter for the life of the wheel. In any case dressing the wheel is a continuing operation and I cannot image operating a grinder without a dresser. My Jones & Shipman has a built in dresser that automatically compensated for the amount dressed, but even a simple diamond point mounted on the magnetic chuck will do the job nicely.
As for cutting the wheels on a waterjet cutter, I have been doing it for almost 20 years not only for cutting the centre, but for cutting whole small wheels (for internal grinding on a jig grinder etc.) out of old wheels that are too small for the surface grinders, or that are damaged. Even when just enlarging the bore, I can get the concentricity within a few thousand by starting the waterjet cut from the original centre.
With a pile of old wheels of every kind, I can produce a special, smaller wheel in minutes without searching for a supplier, waiting and paying. And we all want to support recycling...

My lame attempt at humor seems to be leading down a dressing rat hole. My machine also has a built in wheel dresser that provides position compensation when the wheel is dressed (a very nice feature!). Of course the wheel will be dressed and re-dressed for grinding.

My concern was wheel balancing. Sure, I can balance the wheel but I’d like to not have to. If I have balanced adapters and buy balanced wheels it isn’t required. My question on the water jet method that was suggested was just asking if it was possible to do it accurately enough to maintain the manufacturers level of balancing. The answer I think I am hearing is: No, if you water jet the center hole you will need to balance the wheel. Ok, thanks. It does give me more options for finding wheels for my machine, I appreciate the info.

-Tom

PS: Speaking of lame humor has anyone else ever pointed out the irony of Abrasive Machining” as a forum name and the “abrasive” responses sometimes given in this forum? No offense intended to anyone who is about to use their keyboard to rid themselves of more grit ;-)

To buy a close to size wheel in the case of low-priced wheel like a 6, 7 or 8” diameter. Choose wisely so to know the corner radius can be made with the chosen wheel. A 46 grit wheel might give a .025 corner, and a 80 grit might give a .010 radius corner, and A 100 might give .007 on a good day.
It may be that the radius achieving wheel is too Hard or too Fine for taking the ½” depth in reasonable time. Perhaps a 46 k might take the stock quickly and a 80L for the corner tweek. it is not uncommon to take .495 in a ½” slot, then go in with a 3/8” (or what) harder finer wheel to tickle the .005 depth and .002 sides to finish size and corner.
Dressing side doesan't matter but most often you make one side straight and the other side. To the width needed and the flat dressed side is the side to measure from to best serve your part needs.
Dressing to perhaps 14 and less wide needs a sharp point diamond and much care.. you may need to back brace the wheel .001/.002 at the other side to dress less than a 1/16 x 1” wheel dress..yes they make double diamonds dressers for this.

QT somebody: If you cut the center hole slightly off perfect center the wheel will be unbalanced. How do you insure you are dead center on an existing hole with the water jet?

Wheels should fit the hub close, perhaps .005 or less. One can slip a shim in if needed to better the fit.. The wheel marked .003 shim(if the case) All wheels (new and old) should be marker for *Mount Up.. the every time that wheel is replaced on a mount the mount up is mounted up. This saves dressing amount/ diamond and wheel.

Very large new wheel may have .010 clearance at the hub fit , they are balance and trued with the added clearance down and the the wheel set at the Mount Up notation on the wheel and locked in that position...Tightened with the Mount-Up wrong and they run poor and out of balance until dresses.

An over size hole doesn't matter much once OD dresses but will be way out next time mounted with not having a Mount-Up mark...and so need much dressing again.

If you cut a new hole even a 1/4 inch off center it seems to me that you then dress the outside to that hole.
Once again making a perfect doughnut so why care?
Bob

tome9999 said:

My lame attempt at humor seems to be leading down a dressing rat hole. My machine also has a built in wheel dresser that provides position compensation when the wheel is dressed (a very nice feature!). Of course the wheel will be dressed and re-dressed for grinding.

My concern was wheel balancing. Sure, I can balance the wheel but I’d like to not have to. If I have balanced adapters and buy balanced wheels it isn’t required. My question on the water jet method that was suggested was just asking if it was possible to do it accurately enough to maintain the manufacturers level of balancing. The answer I think I am hearing is: No, if you water jet the center hole you will need to balance the wheel. Ok, thanks. It does give me more options for finding wheels for my machine, I appreciate the info.

-Tom

PS: Speaking of lame humor has anyone else ever pointed out the irony of Abrasive Machining” as a forum name and the “abrasive” responses sometimes given in this forum? No offense intended to anyone who is about to use their keyboard to rid themselves of more grit ;-)

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I still did not get burnt here on any abrasive topic, coolant or not...
I consider balancing a must for any serious operation, and, of course, all jobs are serious jobs....
I find that I must balance any new wheel I buy, and that includes even diamond wheels that are pretty close but no perfect. With use a wheel might need re-balancing. The balancing operation is really simple and not very time consuming - just a few minutes extra work can mean hours saved later. Jones & Shipman wheels adapters have balancing segments in a circular slot that makes the job really easy. My other grinders wheel adapters (Boyar-Schultz and Ingar) did not have this feature but I did add a simple washer (with 12 M3 holes) under the wheel nut. Various thickness and size wights (separated from round blanks) are attached to this disc as needed. Sometimes just a small M3 screw in one hole is all that is needed.

Certainly, there is nothing wrong with wishing better balance. The weight washers are a great idea. I don’t always balance wheels but do side dress some wheels needing better surface finish.

Mach B was originally in Warren Michigan just a mile and a half north of Detroit, and was our source for wheel alterations. It was one of my tasks to take wheels there for altering and speed testing if a wheel needed to be certified for another speed, came in with no markings, and/or reshaping.

Vitrified wheels were crushed to make steps and other alterations like width and diameter. I can’t remember ever having them a wheel but likely that was also a service provided. A small mild steel cup was mounted to a spindle and pushed hard against the wheel. Vitrified being melted glass holding the wheel grits together would let loose and the new wheel shape would be made.

Back to thinning it is good to consider the diamond position and angle to not thin the diamond shank to not loosen the diamond, to dress on the down side so pushing the diamond hold down to the chick or holding fixture, to up feed the diamond a few times so using the point/not the side of the diamond.

Testing the slot width is important because some material may expand into the wheel and some wheels tend to cut wide or narrow to the measured width, so giving a wider slot than desired. Often I would keep a clay wheel for finishing the bottom. corners, and sides to print needs.
Good to test the slot with a jo-block so location and size can be monitored.

Tweaking the wheel width with a cross feed is tricky. Wheels don't cut well with pressure to the side. Often very fine feeds are needed, perhaps only few tenths or microns with each feed and the perhaps a few free passes to spark out..Burning also comes with side grinding a fine grit whee so it doesn't hurt to use coolant for the task. blue-up or grease pencil up is often good.

It is good to consider the slot bottom corner (s) so adding extra depth for the corner radius even if it is only a few microns..many if not most deigns are better served with extra clearance at the bottom of a slot..Yes the mating part can be beveled so adding another operation

Mach-B Grinding Wheel Shaping & Resizing – Winona, Minnesota

Anatomy of a Grinding Wheel : Mach-B Grinding Wheel Shaping & Resizing

(PS ask them if anyone remembers Buck}

Cool thanks. Looks like Mach-B can basically modify wheels to my specs, nice.
-Tom