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Baldor Tool Grinder setup

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T. J.

H-M Supporter - Gold Member
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#1
I recently scored a Baldor model 510 tool grinder in an auction. Sorry, no pics yet, but I'll post some soon. It seems to be fairly new. It had some surface rust on the tables that came off easily with a soak in Metal Rescue. It's missing one of the water trays and one of the table bolts is stripped - I'll be resolving those issues soon. I've already made a new table clamp handle to replace one that was missing.

My main question is regarding the wheels. It is currently outfitted with a green wheel and a diamond wheel. I mostly use HSS tooling aside from a few cemented carbide boring bars. I've read that the diamond wheel shouldn't be used for HSS, but what about the green wheel? If I need to get AO wheels, is a 60 grit alone adequate, or should I get a coarse wheel for roughing?

Thanks as always!
 

4ssss

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#2
The green wheel is also used for carbide roughing, and will rough grind the steel the carbide is brazed to, along with the carbide, basically getting rid of the steel so you can use the diamond. You will get way with grinding HSS with it. It's true that a diamond wheel will load up when grinding HSS, and shouldn't be used. That and the cost of the wheel should make you think twice about using it for that. I'm curious why you don't use brazed carbide tools, they last longer and now that you have a way to sharpen them that would be the way to go.
 
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#3
I think 60 grit is course, I'd get a 120 for finish on hss , sometimes deals on wheels for them come up on eBay , craigslist, and other places. Green and diamond are for carbide as you said. White wheels can be used also for hss tooling. I don't remember all the types but they can be looked up online.
 

benmychree

John York
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#4
The issue with grinding HSS with diamond is not so much loading up, but that the carbon in the HSS reacts with the carbon of the diamond and causes undue wear, or so I have read; having said that, I have not been so very carful of not allowing that to happen, and have not noticed any big effect, this has mainly been on my Gorton 500 cutter grinder, where I have sharpened both HSS and carbide tipped engraving points on it, and also the carbide tipped points have a HSS shank that gets ground along with the tip.
 

BenW

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#5
It is true that diamond wheels will wear faster than normal when used on steel due to the carbon being absorbed by the steel. This is, however, usually negligable as far as I've heard. Diamond wheels are quite cheap on ebay and for a hobbyist they will last very long. They have the big advantage of wearing much slower than aluminium oxide etc. I would just use diamond wheels for everything, they cut steel very nicely and leave a great finish, and you almost never need to dress them.

Sent from my SM-G930F using Tapatalk
 

JohnG

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#6
With high speed grinding wheels, the temperature can get hot enough to set off a metallurgical reaction between the iron in the steel and the carbon in the diamond. The diamond can be eroded and tool steel can be embrittled by absorbing the extra carbon. It isn't an issue at lower speed. 300 rpm sticks in my head as an old rule of thumb for grinding tool steel with diamond abrasive.
 
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