I am bringing up a Baldor "carbide" tool grinder, a No. 500 with tilting
tables that takes plate-type wheels. I have no intention of using green
silicon carbide wheels. My intention is primarily to sharpen HSS tooling.
I have seen suggestions posted here to use diamond wheels. I am looking
at these, and at the prices they command I don't want to buy them in every
grit. I plan to do roughing on a disk/belt grinder and to do just the
finish grind on the HSS tools (mostly lathe tooling) with the Baldor. I have
1. Would these work? http://www.cdcotools.com/ (see the diamond wheels)
2. What grit?
3. Should I also be looking for a white AlOx wheel?
The wheels you looked at on the above site are not suitable for
grinding HSS at the speeds your grinder runs. The diamond will
actually combine with the HSS causing wheel dulling and accelerated
wear. BUT, I have some 5" diameter cast iron rod that can be turned
and faced and used at lower speeds for lapping HSS with diamond paste.
If you want to use tour high speed grinder with HSS you will need to
use CBN wheels. CBN is almost as hard as diamond and will grind steel
without combinong with the steel. If you want I can have my guy drop
off some slices of the cast iron (no charge) to make your own lapping
plates. But even these will need to be run slowly to avoid pulling all
the diamond out of the lap.
McMaster-Carr may be able to special order them for you if no one else
BTW, wouldn't that Glendo grinder you(?) had FS recently be good for
finishing HSS bits? Or maybe you want to "finish" a little more than I'm
It's running pretty good today, yes. The Baldor no. 500 carbide grinder
I just bought vibrated excessively so the seller knocked off about $150
and I got a really great deal. I brought it home and took off one wheel and
then it ran perfectly smooth. Today I looked at the wheel - a nice Norton
46 grit gray aluminum oxide wheel - and it looked OK to me so I thought I'd
try it again. I carefully remounted it and it ran perfectly true, no vibration.
So now I have one gray AlOx wheel and one green wheel. I would like to ask,
though, how you found out about these, and which you would recommend? - GWE
They are in a clearance flyer that was in my last MSC order, received last
week. I bought a 100 grit. I don't use HSS very much, but I am tired of
dressing that damn Norton ALO wheel every time I want to use it. I can
always hand hone if I need a bit smoother than the 100 grit will make it.
The other wheel is a diamond for brazed carbide, which I don't use very
often either. Wish there was a quick-change wheel set-up for Baldor type
Oops, my luck just ran out. MSC has no stock and isn't getting any
more, sigh. They're looking for me, they'll let me know tomorrow, but
as for now, I'm still looking for CBN plate mounted wheels.
Harold, please take it easy on me. I heard loud and clear that diamond
isn't the abrasive of choice for HSS, but lots of guys have told me
that borazon or CBN work really well for a finish grind. A Baldor No.
500 is a "carbide grinder" with tilting tables and plate-mounted wheels,
and it runs at 3450 rpm. which is *way* too fast to grind HSS with
Ok, easy it is. However, I can't see a reason to use anything beyond
aluminum oxide. I especially can't see a good reason to use a carbide type
grinder for HSS. At best, they're too restrictive to be functional.
One of the negatives of using a machine with a table is you'll *never* gain
any skill at sharpening. As long as you permit a machine to do the work,
you'll not progress. You'll also be limited as to how you can apply your
tool steel to the wheel. I refuse to use anything that gets in the way,
including a work rest of any description.
I was brought up through the trade when there was almost no insert carbide
tooling, and HSS was the order of the day, chiefly because brazed carbide
was still relatively new and not nearly as good as carbide is today. I was
on the tail end of Stellite, which damned few that are machining today can
claim. As a result, we were forced to learn to grind tools, or you had to
find different employment. One was taught the basics, then was expected to
apply them to sharpening. I can't think of any better advice for the home
shop type. Any of the dodges you use to avoid learning will simply hold
you captive. That includes the grinder of which you speak.
On Tue, 22 Mar 2005 12:03:58 -0800, "Harold and Susan Vordos"
Whoa Harold! With that logic we should throw away our milling machines
and break out the files. Forget files, we need to use stones. And have
to walk six miles back and forth through the snow. Harold, I learned
how to grind tools by hand and with a grinder and rest. The grinder
will put very nice edges on the tools and give you an example of what
a good grind looks like and and how a sharp tool cuts. The CBN wheels
used on HSS can give the tool a very smooth and sharp edge. Depends on
the grit of course. And wheel wear is negligible.
You must have had it good! I had to walk ten miles each way, and the snow
was deep---almost up to my hips.
Harold, I learned
So did I. Then I learned how to do it better from guys with proper
experience. I didn't close the door on learning.
I do that free hand. *Anyone* can do it, all it takes is a little
The CBN wheels
I don't see that as a positive thing. If you're doing repetitive grinds
on a production basis (cutter grinder), maybe it has its place, but I can do
free hand that which you mentioned, and I don't have to invest a large
amount in a wheel that is restrictive. I have no doubt these wheels are
good-----damned good----but they do not lend themselves as well to offhand
grinding as do aluminum oxide wheels. There are times when you simply
must dress a particular configuration into a wheel. CBN for that, too?
Why limit yourself to an expensive wheel that can't perform all functions?
There are no advantages, and it's far more expensive.
The point I'm trying to make is that all the fancy gadgets in the world
won't substitute for learning the basics. Learn the basics-----the rest
The best lathe men I ever worked with, one of which was likely the finest
man on a lathe of our time, (from South America, and spoke English poorly)
all sharpened tools free hand, for the same reason I do and did. Any rest
simply gets in the way. That's not to say you can't learn to grind tools
with them, but you'll never achieve the level of excellence that others do
without them. Grinding proper chip breakers is a good example of one of
the limitations when a rest is employed.
I respect Harold's opinion. But I find it very hard to hand grind
toolbits with consistant angles and I also tend to generate
multi-facets. Also it takes a very talented person to hand grind
a 1-2 degree relieve angle for a groove cutting tool.
If you can hand grind toolbits great, but I can't and I don't have
the time or inclination to destroy expensive mo-max toolbits.
So I use a carbide grinder with AO wheels to grind HSS toolbits.
I can very consistantly grind toolbits and touch them up.
Maybe I've lost track of the fact that I may have a little talent! I have
never paid for a grooving tool in my life, nor have I used any kind of guide
to hand grind them. It's not difficult for me to hit width, which I do with
the wheel, not by stoning, and I can do it with a single face grind, it's
not chopped up. I also hand grind all my parting tools (typically made
from 1/2" square HSS blanks), and did so when I ran my machines for gain.
I never felt I had any particular gift, although not all the guys I worked
with could hand grind them equally.
One of my friends ran his own shop for years, selling out when a skin
condition became more trouble than he could deal with. He always relied on
insert tooling or had his custom tools done by a shop with a cutter grinder.
He lacked the confidence to do them manually.
Under those circumstances, I agree. You're likely not trying for the
exotic designs that can be accomplished freehand, so your method likely
serves your needs to your satisfaction.
I'd compare this entire concept to using a computer. Many of the readers
here are very adept at running theirs, and rely on systems that would likely
be well over my head. I'm content to limp by using Windows and IE, if
for no other reason, they do what I expect of them. Maybe if I was
better educated in computers I'd have higher expectations.
I see no right or wrong way where it comes to grinding toolbits. My
position in that regard is if you learn the basics and apply them well,
you'll be set free. It gets down to how important it is to each
individual-------just like computers.
I've stood on the shoulders of some giants (to me, anyway) in the machining
industry, so I think I can understand what you're saying. Had it not been
for some outstanding guidance early on in my career, I doubt seriously that
I would be able to do the things I learned to do. You can carry yourself
only so far without additional input. I am the product of those that went
before me, I don't claim to know anything that I've created.
You're welcome to pay a visit any time you'd like----and I'd gladly spend a
day or two with you showing you how I go about grinding toolbits.
I'd better bring a big pile of toolbits for practice though!
Lets see, I got about 90 1/4 inch Rex AAA. Hate to mutulate them so we
better butcher the box of 100 1/4 inch chinese import toolbits first.
I will save the mo-max and tantung for the final exam.
What size toolbit is the easiest to grind? I find it 1/4 inch the easiest
to grind but not nearly as useful at 5/16. 3/8 works ok on my rockwell
lathe but I find they take a lot longer to grind than a 1/4.
On 24 Mar 2005 15:31:50 GMT, email@example.com (Charles A.
Rough em out on a belt sander. It goes pretty quick
Lathe Dementia. Recognized as one of the major sub-strains of the
all-consuming virus, Packratitis. Usual symptoms easily recognized
and normally is contracted for life. Can be very contagious.
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