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Random diamond tip question

Subw00er

Plastic
Joined
Jun 1, 2021
In a $5 lot of machinist tooling, I came into possession of a Rockwell hardness tester bit. It looks a lot like this (even in the original case):
Rockwell Wilson Hardness Tester Penetrator / Indenter Brale “N” | eBay

Penetrators-Diamond.jpg
Rockwell Penetrator "N" brale, "superficial hardness tester, Wilson Machinist Co."

In my research I see its for a hardness test rig, but I don't have that, nor will I ever purchase one. I am wondering if I could potentially use this little diamond tipped bit as a grinding wheel dresser. Do you think it will handle those lateral, shearing loads? I suppose there is some vibration in there too.

I was thinking about making a little jig for it for my bench grinder, and I am on the lookout for a bench surface grinding machine, so I'll have one of those at some point.
 
The indenters, AFAIK, have a specific conical diamond tip vs pyramid as on the diamond dressers. Although it can, probably, be used for dressing, it would be sort of a waste.

I can buy it from you to use as a spare for my hardness tester if it's in a decent shape.
 
I would say the same. Sell it and buy several dressers... I've got one of these kicking around too, been sitting new in the little package for donkeys years. Got it from an old acquaintance who had it sitting around the same way.
 
Ah, ok thanks for the info.

Michael, here are some pics. I did my best to get a closeup with a magnifying glass. My eyes are not the best these days. Upon closer inspection it looks like some clearance grinding was done to the tip support, but the diamond appears untouched. Pm me your info if interested.

IMG_3288.jpg

IMG_3289.jpg

IMG_3290.jpg

IMG_3291.jpg
 
If it looks like that other one you probably won't find any takers. New one looks like so:

5MamHG0.jpg
 
Ah, ok thanks for the info.

Michael, here are some pics. I did my best to get a closeup with a magnifying glass. My eyes are not the best these days. Upon closer inspection it looks like some clearance grinding was done to the tip support, but the diamond appears untouched. Pm me your info if interested.

View attachment 328031

View attachment 328032

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That once-precision lapped diamond has been used as a grinding wheel dresser and is no longer of use on a hardness tester. As I said before, bigger dressing diamonds are very cheap.

Larry
 
Likely it may work OK, but a shame to waste a special purpose diamond for a wheel dressing diamond.

and like larry said it looks like it has already been used as a dresser.

A Norbide stick makes a good bench grinder wheel dresser...even an old brazed carbide lathe tool bit
 
There's no way to tell if it would be any good as a penetrator anymore without a microscope. Under the microscope mine has a smooth and uniform conical shape with a very small spherical radius at the tip - that 0.2mm noted by dian sounds about right from what I saw. The diamond is also completely lapped/polished such that it's crystal clear and I can see right down through it to its base like looking through still water or glass.
 








 
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