Grinding Wheel Wear

[rdhem2]

I am all new to grinding so I will post this here. Recently acquired a Cincinnati #2 T&C grinder. When grinding how do you account for wheel wear? Does not the wheel wear down as you grind? How do they account for 4 and 5 decimal accuracy? Consistently!

I once ask a machine shop owner the same question and his answer was don't worry about it! Being ignorant on the subject I did not question further. So what is the scoop?

""MERRY CHRISTMAS TO ALL""

 

[xalky]

Well yes, the grinding wheel does wear. The amount of wear is dependent on the depth of cut and the amount of Y feed per pass. (How aggressive or not you are.) Also the leading edge of the wheel will wear more than the trailing edge. With all these things in mind, less y feed per x pass, and less depth of cut, will provide a nearly, dimensionally perfect, surface.

If you have to take a lot of material off, redress the wheel before your final surface pass, and make that last cut very shallow and feed less per pass.

Like any thing else, You kinda get a feel for it after you've done a few parts on your surface grinder.

Marcel

 

[Philco]

rdhem2, thanks for asking this question. This is something that has crossed my mind several times before.
There was a video that I saw ( possibly on this site)where the grinder operator ran the machine fast & hard. This almost seemed abusive to the machine & the part being machined. I'm pretty sure that it was Tony Wells that responded in a post related to the video that is the way that he grinds also.
Thanks Xalky for the reply. I learn something every time I get on this site. I guess in a production type of operation it's quicker to run fast & hard for the bulk of the material & recut the wheel for the final cut.
Phil

 

[mcostello]

If You have the items at hand or cannot watch, just touch a piece of steel to a Silicon Carbide-green wheel. The way it disappears has to be seen to be believed.

 

[Mark_f]

My drill bit grinder I built has a diamond wheel. I (in my opinion) think they hold up better and wear better. They are expensive though. Much more than the white cup wheels. I also don't abuse it. I take light cuts. I have sharpened a lot of drills and still haven't had to adjust the wheel. ( when the wheel wears, it will show on the drill points and they are still right on the money.


Mark Frazier

 

[Geezer]

Just my $.02.

Grinding wheels are designed to wear out. They are made up of two elements, the "Grit" and the "Bonding Agent"
The "harder" the metal is that you want to grind requires a "softer" wheel which means the bonding agent is softer and releases the grit at a high rate. That is why a "Green" Wheel wears down quicker than a "Gray" or "White" one, it's bonding agent release dulled grit so sharper grit can continue to work.
Gray and white wheels are used for general work and have a tougher bond to hold the grits on longer because they will not dull as quick with regular steel and each one can produce more work. The green wheels are generally used for carbide which dulls the grit very quickly. To address this the green wheel will drop the grits off quicker because it knows they have gotten dull in a hurry.

Just my $.02

 

[Bill Gruby]

Your Machine Shop Man was correct, you don't worry about it. As each pass sparks out you move the wheel down a bit more. The first pass at a setting is a slow one. At the same setting makes a few more passes. The amount of spark will get less. This is called "Spark Out" here. Just before the finish pass you redress the wheel and make the last cuts till no spark appears. You're done.

"Billy G"