Anyone Use CBN Grinder Wheels?

[leehljp]

Jim, Don't judge every turner by others that you meet, no matter what their ranking is. I do something that a few guys do, (bowl turners) and your AAW turner could not do without some honing. I am sure your AAW guy could do lots that I cannot do. But turning segmented wood and certain metals without a razor sharp honed scraper would only produce smearing. For him to say he needs a little sandpaper - that would destroy some types of turning. He would need to learn how to sharpen his tools more if he had to rely on a little sandpaper.

When turning pens with metallic segments in it, don't even THINK about sanding it. Some metallic dust will smear like pencil lead. The pen wood/metal blanks (with certain metals) MUST be turned down so fine that it does not need sanding. After I discovered that technique on my own - because a couple of long time bowl turners said I couldn't do that, - I learned that some other bowl turners did do that also - finished turning so fine that they didn't need sanding. A finely tuned tool can cut or scrape so smooth that even 400 sandpaper would actually rough it up.

The two pens below, with the contrasting wood and metal smears terribly with sandpaper. When confronted with the problem, most people accept a smidgen of smudge, but not me. I got my scraper out and I sharpened and honed and sharpened and honed and honed for about 30 minutes on an already shaped scraper. WOW, that thing was sharp. I put it to the pen blanks and it was smooth cutting the final .001 or .002 or .003", which cleared the smudges off and left beautifully smooth wood and shiny metal. No Sandpaper needed.

Later, I learned from a few others who were bowl turners that they did the same. There were a few who said that that kind of sharp was not needed. But if they didn't want to or need to, that was their problem.

BTW, like you, I primarily use HSS tools. I have some carbide insert tools but I don't like them because they don't seems as sharp as HSS gets. I primarily use the insert tools for roughing blanks out. I have lots of turning and other hand tools that I need to shape. If you see the Japanese chisels IN the box below, they were never shaped to an edge. I was given those about 14 years ago, but the edges need considerable grinding/shaping. After spending 30 full minutes on JUST one with the Tormek like Grizzly, I knew I was in over my head. CBNs are not a single use tool for me, SHAPING and sharpening.

Add in: the Japanese chisels were given to me by a fellow who made many of his own tools. He also used to go to San Diego yearly and teach Japanese woodworking techniques at a symposium. He taught me some sharpening techniques that I still use. He went once and Sam Maloof showed up to watch him. Sam gave him one of his books, wrote a letter to my Japanese friend and autographed the book. My friend came back to Japan and asked me: "Do you know a man named Sam Maloof?" Me: "Sam Maloof? SAM MALOOF? Wood worker?"

The green bar in the box next to the chisels is a rouge compound bar of sorts that My friend uses to hone his chisels. Rub some on soft wood and hone the edge of the chisels. Long ago, I posted a picture of a ribbon of wood Maeno cut just for me. It was a ribbon about 3 ft long 2 inches wide and so thin you could read the news paper through it. Some people say you don't need that sharpness on lathe tools, but that is their problem.

Lastly, there is a guy on the pen forum that has worked in a machine shop all his adult life. Great at what he does. However, when it comes to sharpening drill bits, 90% will recommend Drill Doctors. That guy will come on every time and chastise them saying it should be and can be done by hand. No need for such equipment; a wast of time. He can not comprehend that he has years of experience and the rest do not. No one will come up to his level of drill bit sharpening in a single day, or two time. For the occasional use person in the home shop, the Drill Doctor is a great tool. Experts prevent many newbies from pursuing great hobbies by chastising them on this issue. There is another guy that chastised newbies incessantly for doing things that he did by hand (with years experience - and he is excellent at what he does) and some people quit because of his rants about the old ways. I had a run in with him about telling newbies that they didn't need to do it a certain way. "Quit being so negative to new ways" I told him. As to the "new" ways these guys have pushed pen making designs way past our old ways because they didn't stop at the limits. New technology equipment allows people to do things old technology has limits on. In some cases, it IS the tool that limits ability to accomplish things in a timely manner. But to each his own, as as one fellow said on another woodworking forum - "Time doesn't cost me anything, so the time it takes to accomplish (make) something is irrelevant." Might be when one is retired!

[woodturner]

I stupidly raised my hand and asked how he honed the tool after grinding.

A lot of turners don't hone, and that works for them. Personally I hone my lathe tools to get a better cut and extend the life of the tool. I think most miniatures turners do as well, it's hard to get clean, sharp definition on tiny details without a very sharp tool.

[Carlos]

I guess I don't really consider myself a turner, and I have very little skill for sharpening tools. Mostly I prod the wife to do it for me. She rarely hones, and says it works well for pens and bowls. She does it on a variable-speed grinder with a white wheel and some tool rests. I'm a flat wood guy and just turn something once a year when I get the itch or am making something round to match furniture and other things.

That all said, would replacing her wheel with CBN provide any benefit? The wheel is in decent shape, despite being many years old.

[leehljp]

I guess I don't really consider myself a turner, and I have very little skill for sharpening tools. Mostly I prod the wife to do it for me. She rarely hones, and says it works well for pens and bowls. She does it on a variable-speed grinder with a white wheel and some tool rests. I'm a flat wood guy and just turn something once a year when I get the itch or am making something round to match furniture and other things.

That all said, would replacing her wheel with CBN provide any benefit? The wheel is in decent shape, despite being many years old.

IF she has a bench grinder, yes, a CBN wheel will provide faster grinding, smoother grinding and cooler grinding. Downside is very fine particles emitted and face mask an absolute necessity.

A lot of turners don't hone, and that works for them. Personally I hone my lathe tools to get a better cut and extend the life of the tool. I think most miniatures turners do as well, it's hard to get clean, sharp definition on tiny details without a very sharp tool.

I hadn't given this much thought until your mentioned it. I did turn a few bowls back in the early 90s and stopped. Then after I got into pens, honing became a fixture with my tools precisely for the reason you mentioned about miniature turning - clean tiny details. Then when I started bowls my last couple of years in Japan and back here, I just kept on honing after sharpening. After using honed tools for a while, they just feel different in turning. I have some .3micron, 1 micron, 5 micron and 15 micron sandpaper strips on tempered glass next to my lathe. After turning for about a minute, I stop and take a swipe or two on the .3 micron sandpaper; about every two to three minutes, I swipe the 1 micron a couple of times and then the .3 micron a couple of times.

What you wrote makes complete sense. Many bowl turners came into pen turning and never mention honing; But fellows who started pen turning first and went to bowls usually honed and continued to hone. Honing does give a better edge. I could not have made those pens without honing the tools.

One strange thing I read about 5 or 6 years ago and cannot find the link now - While most might think like the fellow at the event that Jim attended, this had to do with the Tormek. The renowned turner said the equivalent of this: "I don't care if you DO have a Tormek, (and he did - which is why I was searching on sharpening with the Tormek) a turning tool is not finished in sharpening until you hone it. NO tool comes off of any grinder that does not need hand honing."(He showed the difference between a "Tormek grind" and a "Tormek grind after honing" under a microscope; Big difference.) Totally the opposite of what the fellow said to Jim. Your comment made me remember that.

By The Way - I just posted review of my 20 minutes with the CBN grinder under Blogs/reviews.

[Jim Frye]

I must confess that I also hone the edge after grinding, but it's only on a cotton wheel charged with some honing compound. My grinder has the requisite 80 grit white wheel on one end and the 2" wide cotton wheel on the other end. Low speed for grinding, high speed for honing. Again, since my grinder can be mounted next to the headstock, I sharpen quickly and get back to the spinning work piece. I agree that pen turning does necessitate a very sharp and acurate edge. I used to work with a pen turner, but we never discussed the craft much. I did give him some books/magazines on it and he repaid me with one of his pens. One of these days I'm going to do a bowl and that will bring a whole new set of skills, tools, and fixtures to bear.

[leehljp]

Jim,
To me, honing can be done in different forms and all of it works great if one is used to it. Cotton wheels charged with honing compound will knock the ridges down and whip up the edges, IMO. I can buff with wheels but I end to over feed (both in buffing and honing, which wears the edges down and for pens cause flat spots. I know this is my weakness with cotton wheels but I always want to go one more touch and overdo it. Still, most people with cotton wheels do excellent. That is just my weakness. I do better by hand with buffing and better by swiping on micron sandpaper on glass plate for honing.

[Carlos]

under a microscope; Big difference.

But that doesn't necessarily tell us what the result will be when put to wood. I feel like this is not a science, but 50/50 art and science. A machine milling a piston is a science; a human holding a tool on a spinning piece of wood has an incredible number of variables. I've found this to be true of resawing also; everyone has a different feel and technique, therefore, there are variations in the details like blade choices. I will never ever have anything on my bandsaw other than a Woodslicer. Period. It changed my life. Others say they always have problems with them. My guess is that we have so much variety in wood, technique, environment (dry/wet), etc etc etc.

I'm always looking to improve things so I'll take a look at some CBN wheels. With some medical and family challenges, the wife has barely touched the shop for a couple years. She's just getting back into it, and I sure would love to erase any impediments to that. We have two grinders, she uses the variable speed one on low, and some kind of jib/holder set to keep angles perfect (some big brand, but I can't remember what).

I have to say that her pens are fantastic, because she's fastidious on details and sanding. She says honing doesn't help her at all. We're all different.

[leehljp]

But that doesn't necessarily tell us what the result will be when put to wood. I feel like this is not a science, but 50/50 art and science. A machine milling a piston is a science; a human holding a tool on a spinning piece of wood has an incredible number of variables.

You are right on this. It still is subjective to individuals. However when you take into account a few old timers didn't have the calipers and measuring devices and still made things that were precise and down to 1/1000 of an inch by hand, and then look and compare it under a microscope, for sure you don't have the measurements, that does not mean that it isn't more precise.

There is a story behind this link:
https://www.sawdustzone.org/forum/di...her-poofteenth

Maeno-san dropped by my house in the suburb of Osaka and heard me using a router in my garage. We got to talking. (He was hard to understand although I was fluent in Japanese, his Japanese was just different.) I asked him what he did and he said he made wood planes. I saw him a few weeks later and he said he was making hand chisels. I figured he was a blue collar worker in a tool factory. About 6 months past and he dropped by again. (He lived about 1/2 a kilometer past my house.) When he dropped by this time, he was all excited. "I have been to Palomar College in San Diego" he said. Me: What did you do at Palamar College? Maeno: I taught Japanese woodworking techniques. I was a little puzzled. Then he pulled out a book and a letter. "Do you know a man named Sam Maloof?" He asked. Me: Sam Maloof? Woodworker? Maeno: Yes. He wrote me a letter but I can't read it because it is in English. He gave me a book that he wrote, and he signed it for me.

I am really puzzled at this time. He invites me to his house. I meet his wife. He takes me to the basement and shows me his basement wood working shop. I was floored at the 2 inch wide ribbons so thin you could read a magazine or news paper article through! The links to the pictures in the above link is long gone. I lost the pictures since then too. I commented to Maeno how perfect those 1 meter long ribbons were. Maeno commented back: You need to come back after I have sharpened the hand plane.

The next week, I see his wife in the neighborhood and greeted her, I asked her, What does your husband do for work? Oh, He is an art professor at the Jesuit University in Osaka. He likes to express his personal art in wood. Some of the finest cabinets I have ever seen was in his house.

Later, he called me and said, I have sharpened my plane, come over. When I got there, he said, Do you understand how wood moves with humidity changes? It took me a couple of times questioning him to figure out was he was saying. But I understood. Then he said, I planed this board two days ago, the humidity changes have caused dimensional changes in the soft wood between the hard wood. The soft wood sticks up probably 1/1000mm where as two days ago it was level. He took his plane, took a small hammer, adjusted the depth an angle of the plane blade by tapping the plane, not by turning a knob. After sighting it in, he took one swipe on the board. Instead of one wide sheet that you could see through, there were a dozen STRINGS that came through, it shaved off the soft wood that raised up during the humidity increase.

Now back to your comment, a photograph doesn't prove anything, but sometimes photographs show things that we do know know what they mean or just how right it is.

This brings us to a point: personalities: Some personalities want everything quantifiable absolutely for it to be true;
Some personalities see absolute quantifiables developing way before enough is there to prove it. There is always a tension between these two. Neither are wrong and both are beneficial to each other if we will only let it.

NOTE: WoodTurner gave me a link for trying to find the photo for the web page above. http://archive.org/web/web.php. I tried it with the link from my original and it came back saying that page was unavailable. My picture was hosted on an external site that went out of business.