# Grinding Wheels For Hss?



## Kroll (May 30, 2015)

Guys today I pick up couple of used bench grinders,since I have finally learn that my small lathe is not for carbide.I been watching few Utubes grinding HSS but none said anything about what wheels is needed.I was wondering if someone could provide alittle information on what I need to purchase.I do have some wheels but they look like their just for general grinding.I guess one wheel for roughing to shape then one to put the finishing touches on it.Grinding is new to me,so I guess its done all free hand.If you have pics,links,website,or just general information please let me know-----kroll


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## Karl_T (May 30, 2015)

The literature says to use softer AL O2 wheels...

I just use the standard gray wheels that came with the bench grinder. One ruff and one smooth to finish. YMMV

I do use the AL O2 on the tool and cutter grinder


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## Charles Spencer (May 30, 2015)

Tubal Cain has a three part youtube video that I like a lot:






He does a good job of explaining the angles.  I don't know if I got the idea from this series or from the one he did on sharpening drill bits, but I coated the rest on my grinding wheel with Dykem.  I then marked a couple of angles on it.  Now I use it as a guide to grind bits until they are close to the right size.  I use a gauge to finish it, but having the angles marked means I only have pull the tool from the wheel for the finish.


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## Rex Walters (May 31, 2015)

Take any advice from me with a grain of salt (I'm pretty new at machining) but I use HSS tool bits almost exclusively and have finally gotten the knack of grinding them freehand. It's a very useful skill to acquire. Watch and re-watch the Tubalcain videos or Tom's Techniques for knowledgeable instruction.

The wheels for general grinding are just fine. I don't think the wheel material matters much: gray, blue, or white should all work fine. Doubtless some will wear more quickly and cut cooler than others, but for home hobbyists it shouldn't matter. Do almost all your grinding on a *coarser* wheel: it cuts quicker and cooler. Buy a wheel dresser and keep the wheels dressed. A 6" wheel is fine (you'll want a slower grinder for 8" wheels).

You kinda have to get a feel for the actual grinding, but the only hard part is re-acquiring the same angle after taking a tool off the wheel to examine it. Some things that helped me:

Good lighting and an optivisor to help me see what I'm doing. Seriously: this helps a LOT.
When re-acquiring an angle, start the grind by lightly (!!) touching the part furthest from the cutting edge to the wheel, then rotating the part until you can feel you've re-aquired the bevel (you can tell by touch, but the optivisor helps). A little extra relief usually doesn't hurt, but if you start from the cutting edge and rock back you might risk damaging the edge and having to grind more than you really needed to.
A small handheld diamond hone is also a very useful investment
The best article I've seen on the subject of lathe tool sharpening is: http://conradhoffman.com/advancedsharp.htm


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## GK1918 (May 31, 2015)

Just my habit to save time and hot fingers is to basically mark the blank with a sharpie, clamp the
blank in a vise and hog off most of it with an angle grinder then to finish with a fine wheel. Four inch
grinder wheels are cheap and last. Bench grinder wheels are getting pricey. Another benefit is you
won't have to dress the wheel as often.  I also use a air die grinder with a cut off wheel  for my
so called second stage then the bench grinder.. And I hardly ever stone these, its all in the
proper fine wheel and a surgical hand....
sam


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