Grinder tips

[Tony Wilkins]

Bought an 8” grinder a while back and finally got it out of the box. I hate to admit I’m slightly nervous to use it. First thing I need to get done with it is putting a 10” radius on a plane blade for some hogging work.

What tips do y’all have for me before I apply iron to CBN wheel?

here’s the beast…
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[chuck van dyck]

I’d mount it in a base with tool rests at minimum! After that there’s not much to it but to do it. Practice on something first.
Such a useful tool. Opens up some many possibilities beyond just sharpening. Shaping tools to meet your needs will be a game changer.

[Tony Wilkins]

I’d mount it in a base with tool rests at minimum! After that there’s not much to it but to do it. Practice on something first.
Such a useful tool. Opens up some many possibilities beyond just sharpening. Shaping tools to meet your needs will be a game changer.

It came with tool rests, just need to put them on. What kind of base? Was just going to bolt it onto the workbench it’s on.

[Kevin Jenness]

That is a nice grinder! It won't hurt to bolt it down but I bet it isn't necessary. Just take your time and don't burn the steel. I keep a water vessel nearby.

You'll probably find yourself changing out that gray wheel after you use the grinder a while.

[chuck van dyck]

I have mine on a chunk of 1” europly with little rubber feet. That can then be moved around as needed. I also use the wolverine tool rests. Not necessary but nice to have the extra surface. The steel is very thick which can act as a heat sink. They don’t attach to the grinder but to a surface below.

But like Kevin said, should work great as is and none of the wolverine stuff is really necessary. Enjoy!

[Stephen Rosenthal]

Nice grinder! Anyone ever tell you you look like Bruce Arians, Tampa Bay Buccaneers head coach?

[Tony Wilkins]

Nice grinder! Anyone ever tell you you look like Bruce Arians, Tampa Bay Buccaneers head coach?
No but if I put my hat down in public people give me change.

[Tony Wilkins]

Here is the tool rest that comes with it (picture from suppliers website).
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[Stew Denton]

Tony,

First I set the tool rest at a 90 degree angle to the stone. Next, I spray the iron with lay out blue, let it dry well, and then use a square and an awl, or something similar, to scribe a 90 degree angle across the iron if it needs to be squared up. I then grind to that line holding the blade at a 90 degree angle and grind a small flat on the end of the iron. I place the scribed line as close to the edge as possible which takes off the minimum length of iron but yet still squares things up.

This will give you a small flat on the end of the iron. There are two purposes for this "grind to the line" step. First it squares up the iron, and two, it creates a surface to look at to see how the actual radius you are trying to achieve is coming along. The best way to follow your progress is to look at the edge fairly often, and look at a good light holding the iron between you and the light to see the reflection of the light off the flat on the end of the iron.

Next I use a small piece of heavy cardboard cut to the angle that I want to grind the iron to, and use this to set the tool rest to the correct distance and angle to the grind stone to give the correct angle to the iron as grinding progresses. To set the rest, I eyeball the angle where the cardboard (or popsicle stick or whatever) hits the stone is what is needed. If you want an angle of 30 degrees, the angle you cut on the popsicle stick must be 150 degrees (which is 180 degrees minus 30 degrees.) Remember you want the tip of the iron to be at 30 degrees not the base of the angle at 30 degrees, so the place where the correct angle with the stone and popsicle stick should be a little ways up the stick, not the corner of the angle.

For the actual grinding as you proceed I hold the iron, after the tool rest is set at the correct angle for the radius, with my thumb on top of the iron and my fingers holding the bottom of the iron. I fiddle with the iron until is against the stone to give the needed angle on the business end. This is done with the grinder turned OFF! I then adjust the iron in my hand so that my first finger is parallel with the edge of the rest and laying against the back edge of the rest. This is to act as a guide and as I move the iron across the stone I use my index finger, which is holding the bottom of the iron at a 90 degree to the iron, as a guide to keep the iron at the correct length from the stone and at the correct angle.

I then use very little pressure as I move the iron across the grind stone, dunking the iron in a container of water that I put right beside the grinder after every pass or every other pass, depending on how much of the iron appears to be heating up. Also, I use the index finger of my left hand (I am right handed) to check the iron to check the temperature of the end of the iron.

Again, as I grind I pay attention to the temperature of the iron with the index finger of my left hand against the iron, which also helps me to not overheat the iron. I dunk the iron after every pass, or at least every other pass as I REALLY do not want to over heat the iron. The index finger of my left hand tells me when to dunk. As the flat on the end of the iron gets thinner I dunk more often. When the flat is still somewhat wider it is not necessary to dunk as often, as the critical point is when the flat starts to become very thin. This is followed by a quick with a paper towel to dry the iron before going back to the grinder. I never change the hand position of my right hand holding the iron as such can change the depth for grinding that you have established.

I also only take off only tiny amounts of steel each pass as I get close to the end and check the "flat" on the business edge at the front of the iron very often to make certain that I am taking off equal amounts at all places of the blade. The best way I have found to see the flat is to hold it underneath a good light, and then look down at the reflection of the light off the "flat." I grind the iron down until the "flat" is very thin. I don't try to get the flat on the iron to completely disappear, as this is almost certain to over heat the edge, at least it does for me. Again, I don't like to live dangerously when sharpening with a power grinder for fear of taking the temper out of the iron. Thus I quit grinding when the flat is small enough that it should not take a lot of time to finish it up on a stone by hand.

At this point I turn off the grinder and go to a hand stone to take the edge down the rest of the way to sharpness. In this way I avoid over heating the edge. I would rather quit grinding on the power grinder a little bit early rather than to try to get the flat too thin and thus risk disaster.

Regards,

Stew

[Patrick McCarthy]

Did it also come with a light and plastic shields? i would recommend installing those as well.

On the exhaust side i put loose fitting peanut butter jars (plastic) so i did not end up with the grit all over the place.

[Tony Wilkins]

Great write-up, thanks!

[Tony Wilkins]

Plastic shields, yes. Light, no (at least I don’t think so.)

[scott lipscomb]

Dang Tony, thats a really nice grinder. I have my old Baldor 10" grinder set up with a 180 cbn on one side, and a 1/2" cotton buff on the other side and I can take stuff from blunt to plenty darn sharp with just those two wheels. I like to use my stones, though, because I feel like I am cheating on the grinder.

[Stew Denton]

Tony,

You might want to read my note again, as I went back several times to edit it, and did not finish until about 8:40.

+1 on it being a nice grinder. I may get a CBN wheel eventually also.

Stew

[Patrick McCarthy]

Stew, nice tutorial. Thank you, sir. Patrick

[John K Jordan]

It came with tool rests, just need to put them on. What kind of base? Was just going to bolt it onto the workbench it’s on.

The rests that came with all my grinders were not high quality. I bought several of the OneWay Wolverine bases and rests and threw the others away (well actually, threw them in a box). The Wolverine is very sturdy. This shows the basic base and platform, available from many sources.

https://www.woodcraft.com/products/oneway-wolverine-flat-tool-sharpening-platform-kit

For repeatable angles I make plastic gages to hold against the wheel and very quickly adjust the rest to the precise angle I want, for example:

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I made this one to set the rest for 90" to sharpen curved hand (card) scrapers. I learned to paint the back side of the plastic to better see the gauge.

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I have several of the original rests that come with the Wolverine but for most grinding/sharpening I prefer the mini platform rest. Bought several from Amazon.

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My sharpening station continues to change but this is an earlier picture. I've since added a second Tormek and two more bench grinders in another room. Each is for a specific purpose.

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JKJ

[Charles Guest]

Bought an 8” grinder a while back and finally got it out of the box. I hate to admit I’m slightly nervous to use it. First thing I need to get done with it is putting a 10” radius on a plane blade for some hogging work.

What tips do y’all have for me before I apply iron to CBN wheel?

here’s the beast…
472468

Create the radius freehand on a coarse oilstone and then grind in behind it (NOT all the way to the edge you created at the oilstone, leave a sliver for your fine media) if you want a hollow ground blade. You can scratch in the radius on the flat face with a carbide scriber and then work to it on the stones. Make a template. You're going to have to maintain that shape on stones anyway, might as well learn how to create it there in the first place. What you are describing might take ten minutes, tops. And you won't burn the steel.

There is never a need to grind to a feather edge. Once you understand this, and you'd be surprised how many people don't, then you'll have a real understanding of the process. And once you do understand it, there's no need for water-cooled wheels, special dry wheels that run cool, etc. A plain coarse grindstone is all you need. The one that came with your grinder will work just fine.

[Keegan Shields]

This is genius. Thanks for sharing!

[Kevin Jenness]

Create the radius freehand on a coarse oilstone and then grind in behind it (NOT all the way to the edge you created at the oilstone, leave a sliver for your fine media) if you want a hollow ground blade. You can scratch in the radius on the flat face with a carbide scriber and then work to it on the stones. Make a template. You're going to have to maintain that shape on stones anyway, might as well learn how to create it there in the first place. What you are describing might take ten minutes, tops. And you won't burn the steel.

There is never a need to grind to a feather edge. Once you understand this, and you'd be surprised how many people don't, then you'll have a real understanding of the process. And once you do understand it, there's no need for water-cooled wheels, special dry wheels that run cool, etc. A plain coarse grindstone is all you need. The one that came with your grinder will work just fine.

What's the point of having a grinder if not to save time shaping steel? Friable AlOx and CBN wheels cut tool steel much cooler than the stock wheels, why not use them? Burning is completely avoidable with care. Turners routinely grind to the edge (granted that is typically high speed steel, but still can be done without bluing the steel).
Not saying your way is wrong, but it is not the only way.

[Tom Bender]

Fastening down - if needed you could try just two bolts on the front with wing nuts underneath so it is easy to move when you need your bench for other tasks.

Dust out the back - best to not connect it to your dust collector, don't want to set it on fire (though I have never heard of that happening)
- but then it will shoot dust and sparks onto and behind your bench, I covered the outlets on mine with metal tape

Learning to use it - start out with lawn mower blades

Scrub plane - when I converted my #4 to a scrub it was life changing, you are going to love it. 10" should be plenty, even larger may be good enough.