Forming a radius on a diamond grinding wheel

[michiganbuck]

. One might purchase a Royal Oak Tc grinder with an optical comparator for by-hand dressing .050 (or what) radius to a dimond wheel. Also having a brake dresser mounted on an angle plate on the RO for dressing the wheel diameter to get back where the .050 rad could be made.

That would reduce the wheel dressing time to less than an hour.

Having two plate mounted wheels so one could be sent out to restore would reduce wheel dressing time to near zero.
*One can look at a hand derssed radious with a loupe to see that it is round, and check it with a radius gauge to see it is to size.
At my first grinding job I would run hunderds of single point TCT tool bits by hand on a carbide grinder to a .030 Rad with a +- .002 and never got a reject..yes I had better eyes back then.

 

[michiganbuck]

For a smaller part, perhaps 12 x 12" a CNC Tc grindrer can grind a number of features to a part with one set up. they can also be used as a wheel dressing machine for simple work like radius dressin..
In addition to making and shrpening cutters.

Tool Grinders - Star Cutter Company Tool Grining Machines

Star Cutter provides expert sales and service for the NXT Tool Grinder and UTG Series Broach Grinder.

www.starcutter.com

 

[ZEPMaine]

Hehe, I'm even a little jealous of such a complex and interesting job

We are hiring and I personally am sick of those parts. lol.

Sometimes it can be good to buy a plated wheel, that is a wheel made with the desired form. They don’t have as much abrasive thickness but are very true to desired form/shape.
Sidley Diamond wheels is one outfit.
For a radius one would order the radius on both corners of the wheel.

We use plated wheels as roughing wheels on another tungsten carbide job doing some spherical grinding, but we are restricted to resin or vitrified bond diamond wheels by specification AMS2449.

I actually just this morning received a quote from Meister for vit diamond wheels to accomplish this task and they are quoting $5500-6000 per wheel and $1300 for a hybrid dressing disc. I'm waiting on a few more quotes, but I have a feeling this price will not be too far out of line with the others. Wheels are 200 grit Ø20" x 1" x Ø8".

 

[ZEPMaine]

. One might purchase a Royal Oak Tc grinder with an optical comparator for by-hand dressing .050 (or what) radius to a dimond wheel. Also having a brake dresser mounted on an angle plate on the RO for dressing the wheel diameter to get back where the .050 rad could be made.

That would reduce the wheel dressing time to less than an hour.

Having two plate mounted wheels so one could be sent out to restore would reduce wheel dressing time to near zero.
*One can look at a hand derssed radious with a loupe to see that it is round, and check it with a radius gauge to see it is to size.
At my first grinding job I would run hunderds of single point TCT tool bits by hand on a carbide grinder to a .030 Rad with a +- .002 and never got a reject..yes I had better eyes back then.

I need to make this process easier and remove as much skill from it as possible not add more. lol. I've got to get it where a guy a couple steps better than a button pusher can run it without deviations.

 

[michiganbuck]

What tolerance on your radius.
QT: (I need to make this process easier and remove as much skill from it as possible not add more. lol. I've got to get it where a guy a couple steps better than a button pusher can run it without deviations.) Agree, less chanc to error is good.
And getting plate mounted wheels to run surface finish smoothe is not easy.

 

[ZEPMaine]

What tolerance on your radius.

+/-.010" (aka a mile). It's almost a joke too because this radius and adjacent diameter the radius is tangent to used to be coated with aluminum instead of tungsten carbide. I still haven't figured out what any of the engineers at this customer are smoking where someone thought an aluminum coating would suffice initially, but 8 years later aluminum isn't good enough and they should go straight to carbide.

 

[stephen thomas]

Recomendations for the use, truing and dressing of diamond wheels

When using diamond grinding wheels, the following instructions should be observed: Grinding wheels are to be mounted on holders or flanges and should not be removed until final usage has occurred The tools are to be mounted securely on the machine spindle in accordance with the technical...

pdt.tools

Dressing Technique for Truing Up Diamond Grinding Wheels

This tapered diamond grinding wheel dressing technique, which takes place inside the machine, is used in production of high-precision profile inserts.

www.productionmachining.com

I've dressed radii on diamond wheels with a broken stone, as someone else described. But it was not that precise a requirement, nor for rocket parts.
(It was for making custom carbide woodworking tools)

I do wonder, however, if it was necessary to do on a routine basis on vitrified bond diamond wheels, if a small grinder and green wheel could not be rigged up concentric on a regular R & A dresser. Wheel going cross ways. Then some means to dress the green wheel & find -0- at current diameter, and off you go.

smt

 

[michiganbuck]

A small radius can be added with a soft piece of steel, copper or brass because this load up a diamond wheel and diamonds are pushed off. Then a dressing stick is used to clear off the loading.
Diamond Straight wheels Type-1 that grind on the od. and plate mounted diamond wheels l should be indicated in to less than .002" so at the end of life they don’t waste .015 (or what) that was the original clearance or error in the face mount.
Good quality diamonds run very close to zero at diamonds the where they hit the aluminum or whatever the wheel body is made of.
For plate mounted wheels I just use computer copy paper for shims.
A slip of plastic can be placed to keep indicator point off the wheel,