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metalmagpie
04-25-2012, 11:33 AM
I have a bench grinder with a tilting table setup. The table has a slot in it 0.2x0.5" just like a Baldor tool grinder does. I also have a Baldor clone tool grinder and I want to put an AlOx stone on one side.

I'm looking for a simple to make jig for truing aluminum oxide grinding wheels with a diamond point. I have a little box with 10 or 12 diamond points in it, lots of those, but I need something to hold one and slide it across the slot, then advance it a few thou controllably and do it again.

Plans? Ideas? Someone sell these?

Toolguy
04-25-2012, 11:54 AM
Just make a block out of some mild steel that has the .2 X .5 key milled out on one side. Make a hole for the diamond to go in 90 degrees to the key. Make a hole in the bottom of the diamond hole threaded for a 1/4-20 or some other fine thread. Drill and tap a setscrew or thumbscrew hole in the side of the diamond hole.
To use, put the bolt in the fine threaded hole, slide the diamond in on top of the bolt and tighten the setscrew to hold the diamond from rotating. Swipe across the grinder stone, loosen the setscrew, advance the bolt (and diamond), tighten the setscrew and repeat. If you want to get fancy you could use a cheap micrometer head instead of a bolt to advance the diamond.

lakeside53
04-25-2012, 12:00 PM
Sidewall: simple pivoting carrier that runs in the slot; Thead/bolt to adjust the lateral position of the point.

Swing point around to true the outer edge if required.

dian
04-25-2012, 02:23 PM
lakeside, would you have a picture of link or better description, please?

metalmagpie
04-25-2012, 07:25 PM
lakeside, would you have a picture of link or better description, please?

What he means is a block milled TWO ways. One for a traditional key which would slide in the slot. Also with a blind hole drilled to accept the diamond shank, plus a set screw to clamp it. At the bottom of that hole is a fine-threaded bolt to advance the diamond a small amount between passes. Also, make a 2-way key, consisting of two pieces of key stock fastened together at right angles. To face the periphery of the wheel just fasten in the regular key and slide it sideways. To face the side of the wheel, clamp in the 2-way key, remove the traditional key from the block, and slide the block along the perpendicular key.

Or something like that. Lakeside53 is a brilliant guy who is capable of very precise technical communication but he thinks so fast that often what comes out is difficult to comprehend for us mere mortals. But I work with him a lot so I kind of get what he means.

I think. :-)

metalmagpie

J Harp
04-25-2012, 09:12 PM
I made one a couple of months ago, for use on the HF carbide grinder.

I have a picture but I have absolutely no luck posting pictures. If someone would care to post it I can email it to them.

If it would help, I can take it apart and get pictures of the parts makeup.

Theiskell
04-25-2012, 09:36 PM
Is this what you are looking for?

http://i224.photobucket.com/albums/dd295/theiskell/IMG_4859.jpg

metalmagpie
04-26-2012, 12:54 AM
Is this what you are looking for?

That is indeed what I was looking for. A way to true the periphery of the wheels as well as the face would be nice too .. but thanks!

Forrest Addy
04-26-2012, 04:34 AM
I've been making and using gizmos like Toolguy proposed and Theiskell depicted since 1968 when I went to the heavy tool section. Made dozens of those keyed dressers mostly from cast ion as it behaves better in a dust storm of loose abrasive.

Some HSS tool steels like T-15 crack easily if overheated and it polishes aluminum oxide. Thus you have to dress frequently.

Grinding wheels are consumable cutting tools, my friends. You sharpen them by dressing off the dull abrasive. The better the dress (not the smoothest, a good dress has texture suited for the material being ground) the better the ground surface.

Lew Hartswick
04-26-2012, 08:28 AM
The diamond insert should not be perpendicular to the wheel, but
angled so it can be rotated every few uses to equalize the wear on
the diamond. The commercial ones for the bench grinders we have
at school are about 20 degrees off. The same as when using the
similar dressers on a surface grinder they are tipped off vertical.
...lew...

Toolguy
04-26-2012, 09:08 AM
On those grinders you can have the diamond 90 degrees and tilt the table to create the angle.