Why CBN, or other coated steel wheels are not as good as a a matrix grind wheel......

[Odie]

One huge problem, as I see it, these days, is the great majority of turners don't want to sharpen.......the rise in popularity of the Easywood tools are testament to that. Others will grudgingly do some sharpening, but they want it to be as easy as possible, and don't want to hone.......another problem with current philosophy. Most turners will bend over backwards trying to make sharpening easy and fool proof as possible. There have been advancements, but we've known how to get a perfectly sharp edge for 100 years.......and it involves some hand dressing of the edge. Those who take honing to the next level, will do it on both sides. (This is a discussion for another day.)

Lately, we've seen the influx of coated steel wheels for lathe tool sharpening......up to about 180gt. Without honing, they will produce a sharper edge than any matrix wheel of lesser grit, and this seems to be the point of the current majority thinking. With proper honing, the edge fineness, ie: cutting ability, produced with a wheel of lesser grit (80gt, as example for discussion), far exceeds that edge that can be made with a 180gt wheel without honing. (This is also a discussion for another time.)

Why is a matrix wheel better than a coated steel wheel? There are several reasons......

A coated steel wheel cannot be dressed......pretty simple reasoning, but why is that important? A steel wheel will necessarily have a tolerance introduced between the grinder arbor and the wheel. Bushings will double this tolerance. If a steel wheel has a few thousandths discrepancy of trueness, that discrepancy is there, and will be there.....forever. When dressing a matrix wheel, it doesn't matter about the link between arbor and wheel, and how the integrity of that mating is......it's adjusted to fit one individual grinder to one individual wheel, and dressing accomplishes that.

One place where the steel wheel has a distinct advantage, is the balance of the wheel itself. Coated steel wheels can be balanced at the factory, and will be better balanced from that point. For those who use matrix grind wheels to a high degree of efficiency and integrity, balancing the wheel is an important step in that use. Avoiding balancing can be a crucial mistake, and I suspect is seldom done by anyone at all. Balancing a matrix wheel with the use of movable weights on the arbor plates can result in perfection! (See photo. This was take at least five years ago, where I've balanced nickels on the grinder housing after taking the time to balance the SG wheels with weights.)

Another advantage matrix wheels have over coated steel wheels, is the surface of the matrix wheel can be renewed through dressing. This isn't possible with the coated steel wheel.......so, the result of this is the bonded CBN, or diamond particles wear out. In the shop where I work, we sharpen carbide cutting tools on a diamond coated plate. The ability of that plate to sharpen the carbide degrades over time and use. A matrix wheel that is worn down to the point of needing replacement, will always remove material just as well as when it was new. I believe this is an important advantage to the wood lathe turner......

Currently, the newer turners spend a great deal of money and effort to eliminate, or reduce the need for sharpening, and/or the physical skills required to produce a keen edge......and, as I see it......have failed to produce the sharper edge that we've known how to make since the early days of hand tools. We've done nothing but make reasonably sharp tools much faster and easier to acquire.......but, a finely honed edge can only be had the old fashioned way. When this subject has been discussed previously, we've heard about how a fine edge doesn't last on the lathe. Yes, admittedly this is true, but how much effort is worth having that fine edge? If the object of a turner is simple shapes, it might not matter that much.......but if simple shapes are not the final destination of a turner's individual repertoire, and he desires crisp sharp corners, well executed curves, cleanly cut details, and minimal distortion because less sanding is required.....then, that fine edge is golden!

As with everything woodturning........results are the ONLY thing that matters. Everything else is secondary to that. (The only reason I find it necessary to repeat these words, is it's very apparent that the woodturning community bogs itself down in things that don't positively effect the outcome, instead of what really matters......and, that is results.)

ooc

 

[robo hippy]

Umm, Odie, you really need to take one for an extended test run. After using them for almost 10 years, I don't agree. They, by far outshine any other standard wheel available in every category I can think of except price, but when you consider value for what you get, they even excel there.

robo hippy

 

[Odie]

Umm, Odie, you really need to take one for an extended test run. After using them for almost 10 years, I don't agree. They, by far outshine any other standard wheel available in every category I can think of except price, but when you consider value for what you get, they even excel there.

robo hippy

Hiya Robo...........I didn't expect I wouldn't see any disagreement. I don't own any Easywood tools either, so does this mean I can't have a valid opinion about them, either? Saying you disagree is one thing, but let's introduce a little more conceptual thinking to the mix, ok?

OK, you feel the CBN wheel excels.......I just told you why I feel the opposite, and gave reasons. Might I expect the same?

Say, about 4-5 years ago, you told us you were working on a web site so we could see your current works......ever get-er-done? Sure would be nice to evaluate your input by cross referencing it with your results on a continuing basis.

ooc

 

[Bill Boehme]

One huge problem, as I see it, these days, is the great majority of turners don't want to sharpen.......the rise in popularity of the Easywood tools are testament to that. Others will grudgingly do some sharpening, but they want it to be as easy as possible, and don't want to hone.......another problem with current philosophy. Most turners will bend over backwards trying to make sharpening easy and fool proof as possible. There have been advancements, but we've known how to get a perfectly sharp edge for 100 years.......and it involves some hand dressing of the edge. Those who take honing to the next level, will do it on both sides. (This is a discussion for another day.)

I am almost afraid to ask, but wondering how you came upon your facts ... or is it just speculation? Or just poking a stick in the hornets nest? My observation from interfacing with club members, what I see at the SWAT symposium, and discussions on this forum as well as several others leads me to think just the opposite. And, I am guessing that bending over backwards to make things easier seems contradictory. It may possibly be that most turners are smarter than you give them credit.

I have the same model Delta grinder that you do (23-725) with two Norton 3X stones (a step below your SG stones) and it runs incredibly smooth compared to the typical grinder in which the stones haven't been trued and balanced. However, it isn't as smooth as the grinder running without any stones mounted. The only other thing that needs to be done to a wheel besides truing it, is to correct for side to side wobble (do this before truing). I don't have CBN wheels, but I have used them to sharpen a few tools and will say that they are something to behold. However, as you already know, I am a stinkin' Tormek sharpener which might qualify me as being even more pedantic than you are about sharp edges.

Why is a matrix wheel better than a coated steel wheel? There are several reasons......

A coated steel wheel cannot be dressed......pretty simple reasoning, but why is that important? A steel wheel will necessarily have a tolerance introduced between the grinder arbor and the wheel. Bushings will double this tolerance. If a steel wheel has a few thousandths discrepancy of trueness, that discrepancy is there, and will be there.....forever. When dressing a matrix wheel, it doesn't matter about the link between arbor and wheel, and how the integrity of that mating is......it's adjusted to fit one individual grinder to one individual wheel, and dressing accomplishes that.

From what I have read, it appears that diamond "stones" aren't as durable as CBN. That may be because the nickel plating process that holds the particles bonds better to CBN while the diamonds are basically being "trapped" within the nickel plating. There is another more significant difference: diamond abrasives are much smaller than the CBN particles so the two materials serve different purposes. Also, with smaller particles, the nickel plating is thinner so as the nickel wears away, diamonds are sloughed off.

The CBN steel wheels are much more precise in their machining tolerances that you presume. The bushing don't double tolerances as you claim. In fact they have a snug fit to both the arbor hole in the wheel and to the motor shaft. While the concentricity and wobble in a matrix wheel can be seen by eye, it would take a micrometer to measure the same parameters on a quality CBN wheel.

When you are talking about the cutting surface itself, the question is irrelevant because of surface roughness -- where do you make your measurement? Each particle is going to give a different result regardless of the type of wheel.

One place where the steel wheel has a distinct advantage, is the balance of the wheel itself. Coated steel wheels can be balanced at the factory, and will be better balanced from that point. For those who use matrix grind wheels to a high degree of efficiency and integrity, balancing the wheel is an important step in that use. Avoiding balancing can be a crucial mistake, and I suspect is seldom done by anyone at all. Balancing a matrix wheel with the use of movable weights on the arbor plates can result in perfection! (See photo. This was take at least five years ago, where I've balanced nickels on the grinder housing after taking the time to balance the SG wheels with weights.)

No argument with what you say here.

Another advantage matrix wheels have over coated steel wheels, is the surface of the matrix wheel can be renewed through dressing. This isn't possible with the coated steel wheel.......so, the result of this is the bonded CBN, or diamond particles wear out. In the shop where I work, we sharpen carbide cutting tools on a diamond coated plate. The ability of that plate to sharpen the carbide degrades over time and use. A matrix wheel that is worn down to the point of needing replacement, will always remove material just as well as when it was new. I believe this is an important advantage to the wood lathe turner......

Isn't that apples and oranges. You're talking about diamond abrasives and tungsten carbide. We can't draw any conclusions about CBN and HSS from that. CBN isn't new. Its primary market is industrial and not woodturning. Apparently it has found a place or it wouldn't still be around and gaining favor. I don't have any insight on how long a CBN wheel will last, but there are other things besides longevity that make it worthwhile: not continually needing to put up with with truing and balancing saves money in industrial uses and the elimination of that noxious cloud of dust which is the hallmark of a matrix wheel make the CBN grinding wheel very attractive.

..... When this subject has been discussed previously, we've heard about how a fine edge doesn't last on the lathe. Yes, admittedly this is true, but how much effort is worth having that fine edge?....

I would say that it DOES last longer. A sharper edge cuts with less force which implies less wear. Starting off with an edge that hasn't been honed is where the honed edge will be after it has already cut a considerable amount of wood. Trying to quantify how long an edge will last can be an exercise in futility because hardness of species, green/dry differences, mineral content, grain patterns, roughing/finishing cuts, and countless other things can muddy the waters.

Keep on tilting at windmills.

 

[Odie]

Hello Bill.......Can you tell me how the multi-quote function works?

I'd like to reply in the same way you've responded to me.....breaking down my post to respond to specific areas.

ooc

edit: Will have to be later, as my son and I are leaving shortly for the afternoon. OK, I see the multi-quote function isn't what you've used, but would like to know how to break down a post to respond to individual points, as you have done......

Later......

ooc

 

[hockenbery]

I have not bought a CBN wheel yet.

I actually planned on buying one at the AAW symposium in Tampa last June. But I was dissuaded by a couple of professionals and a sharpening expert whose opinions I sought as to whether they were using them and why, why not.

General consensus was.

1. If you use mostly particle metal tools the CBN puts a better edge on them than the ceramic and AO wheelies.

2. If you know how to dress a wheel a freshly dressed wheel will put as good an edge on m2 and m4 steels.
The freshly dressed wheel will also do an adequate job on the PM steels.

3. As to cost effectiveness. When I was turning a lot, an 8" AO wheel would last about 18-20 months up until it was 6" in diameter and I would replace it.
I now have 2 Norton 3x wheels on the grinder for 3 years and I might get another 2 out of them.
It is unlikely I will be turning long enough to make it a cost effective decision. This is true I a lot of 30 year old hobbyists too.
Also I use a course wheel on my bowl gouges. So I would need two CBN wheels.

Most of the new tools I buy are PM. So I will probably buy a CBN wheel in the next year or so.

From all accounts, the CBN wheels work as well a freshly dressed 3x wheel of the same grit.


Al

 

[Bill Boehme]

Hello Bill.......Can you tell me how the multi-quote function works?

I'd like to reply in the same way you've responded to me.....breaking down my post to respond to specific areas.

ooc

It requires some copy and paste, but it's pretty simple once you do it.

edit: Will have to be later, as my son and I are leaving shortly for the afternoon. OK, I see the multi-quote function isn't what you've used, but would like to know how to break down a post to respond to individual points, as you have done......

Later......

ooc

First copy the beginning of a quote -- the part that has the square brackets -- including the brackets by highlighting it and clicking CONTROL-C.

[QUOTE=name and number]​

Then paste it at the beginning of everything that you want to quote by putting the cursor at the desired spot and hitting CONTROL-V.

Next, copy the closing quote tag by highlighting [/QUOTE] and clicking CONTROL-C. Then put the cursor where you want to end the quote and hit CONTROL-V.

Finally, delete any part that you do not want to quote. Sounds harder than it actually is.

 

[R Henrickson]

Hello Bill.......Can you tell me how the multi-quote function works?
OK, I see the multi-quote function isn't what you've used, but would like to know how to break down a post to respond to individual points, as you have done......

To have something formatted as quoted text, all you have to do is start any block of text to be formatted as a quote with [ QUOTE ] (remove the spaces either side of QUOTE) and end the block with [ /QUOTE ] (same change) -- if I had submitted this with the two commands in proper format (without internal spaces), they would be implemented and become invisible.

Or another way to see how to use the QUOTE formatting commands -- just hit "Reply" for any message and see how the two QUOTE format commands appear. That will format the entire original message as a quote, but inserting the appropriate commands can create separate blocks of quotes.

If you do that, it is always a good idea to preview your message to make sure that every 'start quote' command (QUOTE within brackets) is balanced with a 'end quote' command (QUOTE preceded by / ). If I'm not mistaken, it is simply HTML.

 

[Bill Boehme]

I have not bought a CBN wheel yet.

I actually planned on buying one at the AAW symposium in Tampa last June. But I was dissuaded by a couple of professionals and a sharpening expert whose opinions I sought as to whether they were using them and why, why not.

General consensus was.

1. If you use mostly particle metal tools the CBN puts a better edge on them than the ceramic and AO wheelies.

2. If you know how to dress a wheel a freshly dressed wheel will put as good an edge on m2 and m4 steels.
The freshly dressed wheel will also do an adequate job on the PM steels.

3. As to cost effectiveness. When I was turning a lot, an 8" AO wheel would last about 18-20 months up until it was 6" in diameter and I would replace it.
I now have 2 Norton 3x wheels on the grinder for 3 years and I might get another 2 out of them.
It is unlikely I will be turning long enough to make it a cost effective decision. This is true I a lot of 30 year old hobbyists too.
Also I use a course wheel on my bowl gouges. So I would need two CBN wheels.

Most of the new tools I buy are PM. So I will probably buy a CBN wheel in the next year or so.

From all accounts, the CBN wheels work as well a freshly dressed 3x wheel of the same grit.


Al

That is all good information to know, Al. Since my Norton 3X wheels still have a long way to go before they are worn out, I don't have any plans to replace them with CBN, but I do like them. I actually only have one tool that a CBN would make a big difference in sharpening -- that tool is the big Alan Lacer slab of steel skew which I don't use very often. The CBN wheel puts a beautiful smooth bevel on that tool that my 3X wheels can't touch and the Tormek would take forever to achieve. Now that I have put a good bevel on the skew, I can use my Tormek to touch it up for a long time before any more full bevel grinding is needed.

I saw the Doug Thompson video where he actually favors the 3X wheels that are out of round and bounce a lot, but his situation is unique because he starts with a gouge that is flat on the end and wants to put a grind on it in just a few seconds. He uses heavy pressure and goes through wheels like they're going out of style. Meanwhile, the rest of us are interested in touching up a dulled edge where we have already given it the shape that we want.

One more question for Odie: Do you freehand sharpen or use jigs or both. I could be mistaken, but I got the impression that you somewhat disapproved the use of jigs. With a Tormek, jigs are a necessity. As for freehand sharpening, Johannes Michelsen can do it as well as any fixture, but the great majority of what I have seen generally has more facets on the bevel than there are facets on the Hope Diamond. But, the proof of a pudding is in the eating (or as you say, it's the results that count) and the many faceted tools seem to perform well enough to get the job done. Also, knife makers say that a convex bevel is better than a concave one. BTW, the grind that Johannes Michelsen puts on a gouge is for all practical purposes convex except for perhaps a very thin flat bevel at the cutting edge.

 

[Bill Boehme]

To have something formatted as quoted text, all you have to do is start any block of text to be formatted as a quote with [ QUOTE ] (remove the spaces either side of QUOTE) and end the block with [ /QUOTE ] (same change) -- if I had submitted this with the two commands in proper format (without internal spaces), they would be implemented and become invisible.

Or another way to see how to use the QUOTE formatting commands -- just hit "Reply" for any message and see how the two QUOTE format commands appear. That will format the entire original message as a quote, but inserting the appropriate commands can create separate blocks of quotes.

If you do that, it is always a good idea to preview your message to make sure that every 'start quote' command (QUOTE within brackets) is balanced with a 'end quote' command (QUOTE preceded by / ). If I'm not mistaken, it is simply HTML.

Thanks for adding clarification. Sometimes trying to explain things without drawing pictures or waving my hands makes it harder for me to describe. It's not exactly the same as HTML, but BB code closely emulates HTML most of the time, but not always. BTW, I had a heck of a time figuring out how to get the square brackets without turning it into something that was interpreted by the editor as BB code. I finally figured out that inserting something after the square bracket that isn't interpreted as a command would work (such as your use of a space character). What I did was enclose it inside of bold tags and then put separate bold tags around the enclosed text. Another trick could be to misspell quote as qoute. Using the ASCII string for one or more characters works in some BB editors, but not this one.

 

[robo hippy]

Odie,
The reason I didn't go into more depth was that I have done it so many times before when questions come up about the electroplated wheels. So, once again:

Metal plated wheels can not be dressed. Well no, they can't be dressed, but then they do not need to be dressed, ever as near as I can tell. Because CBN is an abrasive material that is specifically used for grinding hardened steels and as near as I can tell, they just plain don't wear out. Dave is still using his original set and he does way more sharpening than I do. They do go through a break in period, but still seem to cut faster and more cleanly than standard wheels. There can be minimal problems with loading up if you try to grind soft steel, aluminum, or brass on them. I have done this just to see what happens. I can actually see small flakes coming off as compared to the fine metal powder that you get from grinding hardened steel. There can be some loading up of the wheel. To clean it up, just sharpen a standard M2 HSS tool or one of the harder ones on the wheel, and it is pretty much back to normal. After a couple of sharpenings, it is gone. I do get some load up of gunk from the stuff left on my gouges and scrapers from turning sloppy wet wood. A lot of it grinds off as I continue to sharpen other tools. Even with it being slightly loaded up, they still cut very well. If they look really ugly, I take them into the kitchen sink, get them wet and hit them with a plastic bristle brush and some Ajax. Good as new. It is suggested by all the makers that you do not grind soft metals on this wheel. I have done it out of curiosity. Same with grinding carbide on them, it can be done, but I would not make a habit out of it.

Breaking down of abrasive particles is always a question. Diamond is great for carbide, ceramic and similar materials. They do not work on hardened steels like the V10 and M2 HSS. I am not positive about the why, but it has to do with heat. Diamond breaks down way more with heat than CBN does. The only thing harder than Boron is diamond. I have found my diamond hones all seem to load up and can not be cleaned. That has not happened with my CBN wheels, with over 2 years of use.

There is no problem with run out or wobble with the steel wheels. They come with either a machined arbor or bushing. They also come spin and bubble balanced. If you mount them on your grinder and you are getting run out, the problem is with the grinder, not the wheel. The plastic bushings on standard wheels are junk, and should be replaced. I do have one set mounted on an old blue no name grinder from Woodcraft. There is only a tiny bit of run out on one side. It is so minimal that it makes no difference. This range of tolerance is easily with in what you can accomplish with a carefully dressed standard wheel.

There is never ANY risk that a metal plated wheel will blow up.

There is no aluminum oxide dust to deal with.

You do not need a balancing system.

You do not need a cleaning stick/dresser.

The metal dust can be swept into your shavings.

The CNB wheels run a lot cooler than standard wheels, even when dirty.

The 1 1/2 inch width is great. I have never run off the side of the wheel when sharpening. I used to to this on occasion when using jigs and free hand sharpening.

The burr produced from a CBN wheel is by far superior to the ones from standard wheels. This is especially useful if you are a psycho scraper user like I am. No need to burnish a burr at all.

All that being said, many people try them out and then go, 'oh, now I know what the other turners are talking about'. This is why I said that you need to take one for an extended test drive. You can have opinions on tools you haven't actually tried out, but you never know till you have tried them out.

I did have a start with a web site, but had 'issues' with the host. Another one is in the works and will be up in some form before the Symposium. I do have a number of clips up on You Tube, and will grab my link on grinders and grinding wheels and get it over here.

Bill, I hope you come by to harass me in Phoenix. While I don't use my Tormek for any thing other than my kitchen knives, I found I could do a pretty good job of platform sharpening with it. The biggest problem with platform sharpening on it, as well as any other platform sharpening is not the actual sharpening process, it is being able to easily set the exact angles. Maybe I need to make one of my robo rests that will fit the Tormek.

https://www.youtube.com/watch?v=aDYdo1IoyRY


robo hippy

 

[Bill Boehme]

..... Breaking down of abrasive particles is always a question. Diamond is great for carbide, ceramic and similar materials. They do not work on hardened steels like the V10 and M2 HSS. I am not positive about the why, but it has to do with heat. Diamond breaks down way more with heat than CBN does. The only thing harder than Boron is diamond. I have found my diamond hones all seem to load up and can not be cleaned. That has not happened with my CBN wheels, with over 2 years of use.....

From what I have read, CBN is a good conductor of heat while diamond is a very poor conductor of heat. What this means to me is that there is probably a more significant difference in thermal expansion between diamonds and the nickel substrate than there is between the CBN and nickel. The other more obvious part is that the diamond abrasive particles are much smaller (typically 600 grit and finer) than the CBN particles (180 grit in this case). This means that the plating has to be thinner in diamonds because it is normally about 2/3 of the particle size in thickness.

.....All that being said, many people try them out and then go, 'oh, now I know what the other turners are talking about'. This is why I said that you need to take one for an extended test drive. You can have opinions on tools you haven't actually tried out, but you never know till you have tried them out.

Everybody has an opinion. Its validity depends on what it's based on. My exposure to them is very limited, but I like what I see.

.....Bill, I hope you come by to harass me in Phoenix. While I don't use my Tormek for any thing other than my kitchen knives, I found I could do a pretty good job of platform sharpening with it. The biggest problem with platform sharpening on it, as well as any other platform sharpening is not the actual sharpening process, it is being able to easily set the exact angles. Maybe I need to make one of my robo rests that will fit the Tormek.

I haven't given much thought to attending, but given the opportunity to harass, I might need to reconsider. Any chance of talking you into attending SWAT? After about fifteen years, I think that I have finally gotten the knack of quickly setting the platform angle. But, you are right -- the angle generally wants to move in steps. I finally fixed the problem of scrapers wanting to grab the wheel by putting a radius on the bottom edge.

 

[robo hippy]

I do need to get down there some time, but not this year. I have a Labor Day 34th annual event to go to, then after that, I am getting a knee replaces. So, 2 hips done, one knee coming, and that should hold me for a while. I should probably send a robo rest or two down there for the event for door prizes/raffle prizes. Can't remember, but think I did that last year.

Opinions: Well, thinking I was being pretty clever, I mentioned to my dad (91+ and still goes into work every day), 'Opinions are like rear ends, every one has one.' Dad, not losing a second came back with 'Yea, and some of them stink!'

I would love to see you in Phoenix, if not, then some other time.

robo hippy

 

[Bill Boehme]

Now I understand the name robo hippy.

My dad is approaching 93 and if it wasn't for his back, he would be in pretty good health.

 

[Sergio Villa]

I have a dry Baldor with a CBN 80 grit and a grey norton that came with it and a Tormek. I do the shaping with the CBN wheel for turning tools and with the composite wheel for carpenter chisels and carving gouges and sharpen all my tools with the Tormek and hone some of them them.
For carpenter chisels and gouges, honing, which basically removes the burr, is a must. In a sharp edge burr is a dulling element unless it is used as the cutting edge like in cabinet and turning scrapers. Scrapers do not scrape, they cut! They just do it with the burr.
No carving gouges are made with HSS or powder steel. These facts should by themselves show that honing produces a better edge and carbon steel allows to be sharpened to a sharper edge.

Now the point is why turners use HSS or powder steel if they cannot be sharpened to the best edge.
This is because of the speed that power lathes allow and which would ruin the temper of carbon steel and dull it quickly whereas the steels used for turning tools are harder and resist the heat.

Why then turners do not usually hone their tools? I believe for two reason, first because sandpaper takes care of the this (something that would ruin a carving in which real crisp cuts are a must) and second because honing a not super sharp HSS tool is partially useless at least with gouges.
But have you tried a skew or a bedan with and without honing? The difference is enormous and this because the shape of the blade of these two tools allows a cut like that of a cabinet maker chisel. The same is true, in my opinion and little experience, also with the so called german spindle gouges that the old artisan was using in a recent video posted on this forum. This tool cuts the wood like a skew and needs to be honed to reach its best.

A good test to judge the edge of a tool would obviously be the starting grit of the sandpaper but then the skill of the turner, the type of wood and other factors would make even this test useless.
The only thing I can say is that even a six hundred grit sandpaper dulls the cut of a well honed skew on red maple. By pure coincidence I used a skew this morning on ambrosia red maple used for a pepper mill.

 

[hockenbery]

I haven't given much thought to attending, but given the opportunity to harass, I might need to reconsider. Any chance of talking you into attending SWAT? .

Bill,
Phoenix is going to be a great time. Hope you reconsider.
Phoenix and SWAT will be a great 2014.

Bet they sell a lot CBN wheels at both.

Al

 

[robo hippy]

robo hippy: actually the name came many years ago. I have always been a fan of cult classic movies like The Adventures of Buckaroo Bonzai, Repo Man, Brother from Another Planet, and of course the original Robo Cop. Death Race 2000 was so bad it was good, but that is another story... Well, I used to twirl my hammer around my finger like Robo Cop did with his gun, and stick it in my tool belt. I was wearing a big knee brace at the time from having ACL surgery (on the knee that is getting replaced), and a guy on the crew commented, 'Hey, it's robo hippy'. I liked it, and when I first started on the forums, it made a good alias.

Now, the latest Robo Cop movie, it was good, but they left out the gun twirl. That is sacrilege.... That is like trying to make The Princess Bride without Andre the Giant playing Fezzik (who was an actual person, but that is still another story......

robo hippy

 

[Bill Boehme]

You didn't mention Attack of the Killer Tomatoes or Gargoyles, those were so bad that nothing can change rhat.

BTW, I forgot to mention earlier that diamonds are no longer the hardest abrasive. A new allotrope of Boron Nitride with a 3D hexagonal structure called Wurtzite Boron Nitride (w-BN) is actually slightly harder.

 

[Odie]

I have a dry Baldor with a CBN 80 grit and a grey norton that came with it and a Tormek. I do the shaping with the CBN wheel for turning tools and with the composite wheel for carpenter chisels and carving gouges and sharpen all my tools with the Tormek and hone some of them them.
For carpenter chisels and gouges, honing, which basically removes the burr, is a must. In a sharp edge burr is a dulling element unless it is used as the cutting edge like in cabinet and turning scrapers. Scrapers do not scrape, they cut! They just do it with the burr.
No carving gouges are made with HSS or powder steel. These facts should by themselves show that honing produces a better edge and carbon steel allows to be sharpened to a sharper edge.

Now the point is why turners use HSS or powder steel if they cannot be sharpened to the best edge.
This is because of the speed that power lathes allow and which would ruin the temper of carbon steel and dull it quickly whereas the steels used for turning tools are harder and resist the heat.

Why then turners do not usually hone their tools? I believe for two reason, first because sandpaper takes care of the this (something that would ruin a carving in which real crisp cuts are a must) and second because honing a not super sharp HSS tool is partially useless at least with gouges.
But have you tried a skew or a bedan with and without honing? The difference is enormous and this because the shape of the blade of these two tools allows a cut like that of a cabinet maker chisel. The same is true, in my opinion and little experience, also with the so called german spindle gouges that the old artisan was using in a recent video posted on this forum. This tool cuts the wood like a skew and needs to be honed to reach its best.

A good test to judge the edge of a tool would obviously be the starting grit of the sandpaper but then the skill of the turner, the type of wood and other factors would make even this test useless.
The only thing I can say is that even a six hundred grit sandpaper dulls the cut of a well honed skew on red maple. By pure coincidence I used a skew this morning on ambrosia red maple used for a pepper mill.

Hi Sergio.......nice to see some other opinions, here......

Yes, a scraper does cut, and it cuts cleanly, if done properly. "Properly" is the key word. The edge on a scraper doesn't last long, but that can be said about any lathe tool.

It would be hard to deny the use of sandpaper, but it's important to limit it's use. The main reason for this, for the purpose of bowl turning, is to keep as perfect a shape as possible. Sandpaper removes wood quicker on the long grain than it does on the end grain. Virtually everything that I feel is important about my turnings, corners, details, curvature......is directly the result of eliminating as much need for sanding as possible. This is why honing is extremely important to me. The super sharp edge won't last as long, and this will be unsatisfactory for some other turners......but, maintaining a perfect geometrical shape, while requiring minimal sanding is key to the kind of results that grab the eye of the onlooker.

========================

Bill.......I guess it's just best to allow you your say without engaging. There are many opinions on woodturning, and we are all entitled to them.

I'll say one thing, though.......you are absolutely right that I'm one who takes great pride in "tilting at the windmills"! Without the ability to see what others don't see, and to "dream the impossible dream", I would neither be who I am, nor do what I do......

ooc

 

[n7bsn]

Odie,
....
The burr produced from a CBN wheel is by far superior to the ones from standard wheels. This is especially useful if you are a psycho scraper user like I am. No need to burnish a burr at all.
....


robo hippy

Robo, try the following, set a platform at say -20 (or 110 on a RoboRest) and place the scraper upside-down. Then sharpen the scraper, I believe that this produces a more consistent burr then the conventional method sans burnishing.

On my "round to it" list is putting a 110 setting on our RoboRest

But I think you did a fine job of demolishing Odie's straw-man arguments.

I'm minded of two quotes "Yes the CBN produces a finer tool edge, but I prefer the more serrated edge from a friable wheel" Mike Mahoney at the Olympia Symposium the year D-Way started selling CBN wheels
and "Dave (eg D-Way) has changed tool sharpening forever, I can get a fine enough skew edge I don't need to hone" Eli Avisera at an all-day class in Bremerton the same year.

Actually there is a third one "As soon as we can afford it, we are getting one of these wheels", my wife, after using one for the first time, at the all-day class from Eli that year.

 

[robo hippy]

You can do a negative angle with the robo rest. If you push the rest past the last stop, and slip the pin through so that it rests on the frame of the rest and not through the tubes, you get about 75 to 80 degrees negative, which is in the range of scraper angles. It may be a bit less on the Oneway compatible version, but I don't have one of those set up in my shop. I will play around with it next week some time. Today, I have to get my sun flower jungle mostly planted.

robo hippy

 

[Richard Findley]

I've been reading this with interest. I've been tempted with a CBN for a while now but not sure I can justify the expense.

The grinder I use is an 8" slow runner which is fitted with its original 120g white wheel. This is now about 5 years old and has only lost about an inch of diameter. The whole set up cost me about £135 which is about 230 dollars. A new CBN wheel (just checked the D-Way site as it seems most popular) would be 185 dollars plus shipping to the UK. A new White would cost me about £40 (70 dollars)

Everyone I have spoken to raves about CBN, apart from one friend of mine who thinks that, although it gives a really nice edge, it doesn't seem to last long. He is the only one, but I trust his judgement as a professional turner with a scientific background.

I know of one pro that says his CBN is beginning to show signs of wear after a couple of years of use.

Just can't decide. Will be in Phoenix so look forward to joining discussions on the topic. Might also like to see that Robo rest too if you're in a booth RH!

Cheers

Richard

 

[Bill Boehme]

I just checked the OptiGrind web site in the UK and you might possibly get a better price than ordering from D-Way over here. A nice feature of their CBN wheels is abrasive on the side.

Here is what they had to say about diamond abrasive wheels:

Diamond is chemically pure carbon. When it is used as a grinding grit it works extremely well with tungsten carbide or glass. With steel, this is a different matter: At comparatively low temperatures the diamond (carbon) forms carbides with some of the ingredients you have in every steel, nickel, chromium. That means the diamond is gone, your diamond grinding wheel is destroyed.
​

 

[robo hippy]

Richard,
I do have a booth there, and will be right next to Doug Thompson. Now isn't that a dangerous set up!!!!

robo hippy

 

[Sergio Villa]

I'm minded of two quotes "Yes the CBN produces a finer tool edge, but I prefer the more serrated edge from a friable wheel" Mike Mahoney at the Olympia Symposium the year D-Way started selling CBN wheels
and "Dave (eg D-Way) has changed tool sharpening forever, I can get a fine enough skew edge I don't need to hone" Eli Avisera at an all-day class in Bremerton the same year.

I do not dispute your quotes of course, but Eli Avisera as you mentioned honed his skews. Honing primarily is done to remove the burr and secondarily to remove other imperfections left by the wheel and thus polish the edge. If you look at a skew just sharpened with a CBN wheel you can notice an heavy burr that can be felt also with a finger. It may vary with the speed of the grinder etc but the burr is there and visible. That burr interferes with the edge and dulls it while using the tool and then is removed by the turning wood but at this point the edge is no longer perfect. It still cuts but is not perfect. In spindle turning, with a perfect edge the skew can easily leave a surface that does not need sanding. The burr interferes with this.

The edge left by the CBN wheel is identical to the one left by a similar grit composite wheel. The difference is in the less heat produced and faster grinding.

 

[Bill Boehme]

.... The edge left by the CBN wheel is identical to the one left by a similar grit composite wheel. The difference is in the less heat produced and faster grinding.

Not in my limited experience using a 180 grit D-Way CBN wheel. In fact I would say that the edge quality was almost as good as one from the Tormek. There was no discernible burr. Do you have the skew lying flat on a tool rest so that there is no bevel pressure against the wheel or are you using something like the Wolverine to sharpen a skew. There will be a big difference because the greater grinding pressure from using a Wolverine jig would definitely result in a burr. I would still hone the edge after sharpening on a CBN wheel, just as I would hone the edge after using the Tormek wheel.

 

[Sergio Villa]

Not in my limited experience using a 180 grit D-Way CBN wheel. In fact I would say that the edge quality was almost as good as one from the Tormek. There was no discernible burr. Do you have the skew lying flat on a tool rest so that there is no bevel pressure against the wheel or are you using something like the Wolverine to sharpen a skew. There will be a big difference because the greater grinding pressure from using a Wolverine jig would definitely result in a burr. I would still hone the edge after sharpening on a CBN wheel, just as I would hone the edge after using the Tormek wheel.

Bill, I (try to) sharpen the skew like Eli Avisera does it: I use the platform to rest my hand an go down and up with the tool making the edges round and not concave. No pressure at all, just the weight of the tool. The CBN wheels leaves a burr in any tool in fact scrapers are often ground on CBN wheels, see Robo.

Any rotating grinding wheel that touches a metal surface leaves on it a burr, irrespective of the direction of rotation. The burr is not an accumulation of metal particles but is due to the pressure of the rotating wheel touching the metal,heat and pressure greatly influence this process but the formation of a burr is inevitable.

Industry spends enormous amount of money in removing burrs from machining activity. You know this.

The edge is related to the grit. The Tormek wheel set on a fine grit is equivalent approximately to a 1000 grit stone, it is lubricated and cooled with water and run at 90 rpm and in spite of this it leaves inevitably a burr. In fact, the burr left by the Tormek on a scraper leaves on the wood a much finer surface than the burr left by the CBN wheel.

 

[robo hippy]

Well, I can raise a burr with any wheel I have ever used, including a 320 grit CBN matrix type wheel, 180 and 80 grit CBN electroplated wheel, and a Tormek both with the coarse wheel and the 'graded' wheel where you could supposedly load it so it was a finer grit. How much of a burr you get depended on the coarseness of the wheel, and how hard you pushed into the wheel. The coarser the wheel and the more sharpening pressure you use, the bigger the burr is. With a very light touch, you might get 'no discernible burr' which to means there is one, but it is pretty tiny. I think the only way to get rid of any burr is to hone it off, or break it off as you turn if you have a fine wire burr. I do know one turner locally who is self taught and is a master spindle turner. She uses a 6 inch, 60 grit grey wheel and doesn't hone. Go figure..... I have been told by a number of people that it is impossible to burnish a burr on high speed steel with a hand burnisher. Well, I can do it, and not because I am using brute strength.

I did try an upside down grind on my scrapers for some turning this afternoon. General impression is that it is not any sharper for a shear cut, and for sure dulls/bends over/breaks off way faster than the right side up burr. I was able to get my rest to about 75 degrees, or 115 degrees depending on how you look at it.

robo hippy

 

[Jeff Deutschle]

When there is debate about tool sharpening at our club, the dry-wheel, non-jig crowd are usually silenced with statements like "I'd rather be turning than sharpening." or "A jig gives you the same geometry every time." The reason I tend to be silenced by these statements is the falseness and stubbornness of the arguments hides the ignorance behind them. There is a saying "Respect fools to avoid noise." I can keep my tools sharp with a quick honing and never leave the lathe. When I do regrind, I don't have to mess with a jig. When using a jig, the geometry does change depending on how long the tool is kept at a given part of the sharpening swing.

What I think is really going on is people look to gadgets to solve their problems. It seems a quick and easy thing to get x-brand grinder with y-brand wheels and z-brand jig and you too will be "turning like a pro!" After all, how can you expect to turn like Mr. McGillicuty (or whoever) unless you have their "signature" grind and t-shirt. (The wood can tell the difference and won't behave, you know. )

The thing is, for the vast majority of us this is a hobby not a profession. Time should be spent on really learning what you are doing. I'd rather turn one bowl a week and learn for myself how different grind angles affect the cut than knock out half a dozen and not learn a thing. (But then I am more of a spindle turner, that actually likes to use a skew, and the AAW, this forum, and our local club is really about bowls, bowls, bowls. sigh...)

Consider this. The act of presenting a tool to a spinning piece of wood is very similar to presenting a tool to a spinning abrasive wheel. If you can do the one, you should be able to do the other. If you can only do the one, you may be able to learn something by doing the other.

Anyhoo, this is just the perspective of a dedicated hobbyist

 

[Bill Boehme]

... Any rotating grinding wheel that touches a metal surface leaves on it a burr, irrespective of the direction of rotation. The burr is not an accumulation of metal particles but is due to the pressure of the rotating wheel touching the metal,heat and pressure greatly influence this process but the formation of a burr is inevitable.
....

The edge is related to the grit. The Tormek wheel set on a fine grit is equivalent approximately to a 1000 grit stone, it is lubricated and cooled with water and run at 90 rpm and in spite of this it leaves inevitably a burr. In fact, the burr left by the Tormek on a scraper leaves on the wood a much finer surface than the burr left by the CBN wheel.

Sergio, you are correct that there is always a burr -- even with the Tormek. I try to remove it as much as possible on a skew by flipping the tool from one side to the other and making a feather light pass across the stone just to eliminate the burr as much as possible after the tool has been sharpened.Most of the time I can't see the burr except for maybe a glint in direct sunlight. A quick honing on the leather wheel gets rid of that last remnant of a burr.

About the edge smoothness being related to the grit -- yes, but that is only part of the story -- the difference between applying heavy or light tool pressure is more noticeable than just changing grits. You mentioned that you use an 80 grit CBN wheel so it would not be surprising that the edge is the same as with a matrix wheel. Generally, the 80 grit CBN wheel is for rough shaping and the 180 grit CBN wheel is used for sharpening. Even at 180 grit it removes steel at a surprisingly fast rate compared to other types of abrasives. I think that if you try a 180 grit wheel, the difference in edge smoothness would be quite noticeable.

Well, I can raise a burr with any wheel I have ever used, including a 320 grit CBN matrix type wheel, 180 and 80 grit CBN electroplated wheel, and a Tormek both with the coarse wheel and the 'graded' wheel where you could supposedly load it so it was a finer grit. How much of a burr you get depended on the coarseness of the wheel, and how hard you pushed into the wheel. The coarser the wheel and the more sharpening pressure you use, the bigger the burr is. With a very light touch, you might get 'no discernible burr' which to means there is one, but it is pretty tiny. I think the only way to get rid of any burr is to hone it off, or break it off as you turn if you have a fine wire burr. I do know one turner locally who is self taught and is a master spindle turner. She uses a 6 inch, 60 grit grey wheel and doesn't hone. Go figure..... I have been told by a number of people that it is impossible to burnish a burr on high speed steel with a hand burnisher. Well, I can do it, and not because I am using brute strength...

With the Tormek, given that it runs cool, any discernible burr isn't going to be very useful. The way that I create a burr is first hone off any remnants of a wire edge and then use cabinet scraper burnishing tool to raise a burr. I prefer this type of burr over the type left by a grinder because it is more aggressive and much longer lasting. I create the burr by first pulling the burnisher across the top surface and then across the bevel surface. It takes some practice. If too much pressure is applied it will cause the burr to roll back too far. If the pressure is too light, the burr might not develop. Use only one drag of the tool or else it will cold work the steel (cause it to be brittle). If you haven't tried this before, I think that it would be worth giving it a shot. Who knows, you might even like it.

BTW, those folks who say that you can't use a burnisher to raise a burr might be doing it wrong. It actually takes surprisingly light pressure from the burnishing tool to do it right.

 

[robo hippy]

One interesting thing about the CBN wheels, the 80 grit CBN wheel leaves a much more polished surface than an 80 grit standard wheel. If you use the matrix type with about 3/16 inch of abrasive mix bonded to an aluminum hub (similar to the Woodcraft diamond wheel, not sure if they carry it any more or not), the surface is even more polished. I don't know why this happens. I do go back and forth between sharpening tools on my 80 and 180 grit wheels. I can't really say I notice much of a difference in the performance cutting edges. Minimal at most. This brings us back around to the Mahoney 'I like the more serrated edge because it cuts better'.

There are a lot of myths about the free hand platform sharpening. One is that it wastes more steel, or that you grind off more when compared to jig sharpening. This is just not true. Some of the free hand sharpeners do use a very coarse grinding wheel. This could be part of that. A lot of us tend to way oversharpen, which means instead of one pass to sharpen, we make several. This does waste steel.

Another is the changing geometry/facets/inconsistency of free hand sharpening. My gouge noses never seem to be perfectly centered. The wings never seem to match perfectly. There are tiny facets in the bevel. I had the exact same problems when I used jigs. Point to make here is that the tools do still cut, and cut well. Next time to the wheel, I correct a little, and turn some more.

Finally the part about it is too difficult for a beginner to learn. Well, the exact same set of skills you use to turn, are used to free hand sharpen. Anchor the tool on the tool rest, rub the bevel and cut. You roll and sweep your tool just like you do when cutting wood.

robo hippy

 

[Sergio Villa]

Sergio, you are correct that there is always a burr -- even with the Tormek. I try to remove it as much as possible on a skew by flipping the tool from one side to the other and making a feather light pass across the stone just to eliminate the burr as much as possible after the tool has been sharpened.Most of the time I can't see the burr except for maybe a glint in direct sunlight. A quick honing on the leather wheel gets rid of that last remnant of a burr.

About the edge smoothness being related to the grit -- yes, but that is only part of the story -- the difference between applying heavy or light tool pressure is more noticeable than just changing grits. You mentioned that you use an 80 grit CBN wheel so it would not be surprising that the edge is the same as with a matrix wheel. Generally, the 80 grit CBN wheel is for rough shaping and the 180 grit CBN wheel is used for sharpening. Even at 180 grit it removes steel at a surprisingly fast rate compared to other types of abrasives. I think that if you try a 180 grit wheel, the difference in edge smoothness would be quite noticeable.

I have an 80 grit CBN wheel exactly for the reason you mention: shaping the edge. With two exceptions, scrapers and skew. The reason is that with a diamond hone I usually get a satisfactory edge on the skew, and I rarely use the scrapers for finishing cuts. When I need that special edge I use the Tormek.

PS: another big advantage of shaping with an eight inch wheel and sharpening with a ten inch wheel (Tormek) is that in this way one gets a beautiful and tiny secondary bevel to ride the gouge.
Unfortunately this is not happening on my Tormek because its wheel is approaching the seven inch mark.

 

[hockenbery]

There are a lot of myths about the free hand platform sharpening. One is that it wastes more steel, or that you grind off more when compared to jig sharpening. This is just not true. Some of the free hand sharpeners do use a very coarse grinding wheel. This could be part of that. A lot of us tend to way oversharpen, which means instead of one pass to sharpen, we make several. This does waste steel. Another is the changing geometry/facets/inconsistency of free hand sharpening. My gouge noses never seem to be perfectly centered. The wings never seem to match perfectly. There are tiny facets in the bevel. I had the exact same problems when I used jigs. Point to make here is that the tools do still cut, and cut well. Next time to the wheel, I correct a little, and turn some more. Finally the part about it is too difficult for a beginner to learn. Well, the exact same set of skills you use to turn, are used to free hand sharpen. Anchor the tool on the tool rest, rub the bevel and cut. You roll and sweep your tool just like you do when cutting wood. robo hippy

The big issue is that it takes a long time to learn to sharpen without jigs.
An expert at sharpening probably makes a better edge with less grinding than a novice with a jig.

I use an Ellsworth jig for my bowl gouges, it is the only tool I sharpen with a jig.
Spindle gouges just the wheel and the top of my thigh for support.
Scrapers, skews, parting tool a platform
Hollowing tools the platform to rest my hand on
Michelson grind the platform to rest my hand on.

Sharpening with a jig is not fool proof. The tool's edge still has to be moved over the wheel.
However sharpening with a jig can be taught and learned in a few minutes and produce consistent results.

I used to sharpen my bowl gouges with just the platform and got good results but I lacked the consistency to keep the grind in the original profile and on occasion I would take off too much in a spot. This required several minutes to reshape the gouge to the target profile. The jig made every sharpening the correct profile and saved the corrective grinding that I would have to do every so often. The corrective grinding is what removes more steel than the jig.

Jigs are really fast to use. But it is a choice.

Al

 

[DOCworks]

As with everything woodturning........results are the ONLY thing that matters. Everything else is secondary to that. (The only reason I find it necessary to repeat these words, is it's very apparent that the woodturning community bogs itself down in things that don't positively effect the outcome, instead of what really matters......and, that is results.)

Odie, I think that your statement is correct, but I don't think you believe it unless others outcome is done your way. Otherwise you wouldn't have gone on about the easy wood tools. They can start with 40 grit (I'm kidding guys) and work to the same finish as anyone else, although there will be a lot more dust. I don't care for the easy wood tools (except for certain situations) and use "traditional" tools from Doug T. I have and use Norton 3x, SG and 4 CBN wheels for D-Way. I have balanced and used the white wheels, gray wheels and the Nortons AND I have a tormeck (a very expensive dust collector). I believe if you had put "in my opinion" in your title it would have been a better statement rather than giving the accretion that you have compared fully the wheels in question. I have. I love the Norton 3X's best bang for the buck. The SG's put a beautiful edge on a tool, but are more expensive AND the big issue I have with them is this if they are out of balance you can't fix them. They have a 5/8" hole so all you can do is get the wobble out, but even if you get the wheel perfectly round it will still have vibration. The 3X has a 1" hole and you can work with that. You will say well you should have sent it back....thanks, I didn't think of that. The CBLs are expensive, but I don't have to balance them, they don't have wobble, I don't have to surface them AND I don't have matrix dust in my shop or lungs. This is a big issue with me since my diving accident in '86', blew out my left lung, I had to even quit smoking.

While I like and respect your opinion; on this I think you are wrong.

I do think you are spot on about sharpening! This is a skill that we don't not give enough attention, respect or education too. While I think your process is wonderful for you, I don't want to spend as much time with a hone. So I start with 180 grit sandpaper instead of 220.

One more point I would like to make is this, I am very picky about my tools and how they are sharpened and as more and more turners are getting the CBN wheels I feel less of a need to take my grinder with me. We have a group that meets every Wednesday night out at Danny H's house and since the purchase of the CBN all I have to take is my "special" Don Geiger arm and varigrind and my tools are sharpened just like at home. Same with our clubs grinder. Now I'm not suggesting everyone one needs to buy one, I'm not, but I am pointing out a often overlooked benefit.

CBN wheels while not perfect...there is someone out there selling a version for around $125 which is very close to your SG wheel...you can have mine after you pry my gun out of the other hand. ;-)

 

[Odie]

Odie, I think that your statement is correct, but I don't think you believe it unless others outcome is done your way. Otherwise you wouldn't have gone on about the easy wood tools. They can start with 40 grit (I'm kidding guys) and work to the same finish as anyone else, although there will be a lot more dust. I don't care for the easy wood tools (except for certain situations) and use "traditional" tools from Doug T. I have and use Norton 3x, SG and 4 CBN wheels for D-Way. I have balanced and used the white wheels, gray wheels and the Nortons AND I have a tormeck (a very expensive dust collector). I believe if you had put "in my opinion" in your title it would have been a better statement rather than giving the accretion that you have compared fully the wheels in question. I have. I love the Norton 3X's best bang for the buck. The SG's put a beautiful edge on a tool, but are more expensive AND the big issue I have with them is this if they are out of balance you can't fix them. They have a 5/8" hole so all you can do is get the wobble out, but even if you get the wheel perfectly round it will still have vibration. The 3X has a 1" hole and you can work with that. You will say well you should have sent it back....thanks, I didn't think of that. The CBLs are expensive, but I don't have to balance them, they don't have wobble, I don't have to surface them AND I don't have matrix dust in my shop or lungs. This is a big issue with me since my diving accident in '86', blew out my left lung, I had to even quit smoking.

While I like and respect your opinion; on this I think you are wrong.

I do think you are spot on about sharpening! This is a skill that we don't not give enough attention, respect or education too. While I think your process is wonderful for you, I don't want to spend as much time with a hone. So I start with 180 grit sandpaper instead of 220.

One more point I would like to make is this, I am very picky about my tools and how they are sharpened and as more and more turners are getting the CBN wheels I feel less of a need to take my grinder with me. We have a group that meets every Wednesday night out at Danny H's house and since the purchase of the CBN all I have to take is my "special" Don Geiger arm and varigrind and my tools are sharpened just like at home. Same with our clubs grinder. Now I'm not suggesting everyone one needs to buy one, I'm not, but I am pointing out a often overlooked benefit.

CBN wheels while not perfect...there is someone out there selling a version for around $125 which is very close to your SG wheel...you can have mine after you pry my gun out of the other hand. ;-)

Howdy Doc.......

Well, yes......I absolutely do believe what I said. I base my opinions on what my results are, and I am not unaware of other opinions. Is there anything that rivals the importance of results? I feel there isn't, but no matter.....I'm willing to concede that my opinions, aren't accepted universally in the woodturning community. Clarification: When I mention results, what I speak of is results on the finished turning......not results in the grinding process.

Another person said something that I wholeheartedly agree with.......the grinding is only a method of removing metal. Many turners take their tools directly to the work from the grinder, but if an edge that cuts as cleanly as possible is the objective, grinding is only a step in the overall process.

I'm using a SG 80gt wheel, and it grinds cleanly and quickly with a minimum of heat......but the edge I require is not the result of what I get with the SG. For me, I hone on both sides, so the initial grinding is secondary. This same thing would apply, if I had a CBN.

One point that is particularly valid.....in my belief......is the CBN, or diamond, will wear, and a matrix wheel will cut as well when it's worn down, as when it was new.......I think that is an important thought, but maybe not so much for someone who doesn't turn frequently.......When the latter is the case, then the CBN might last a lifetime.

ooc

 

[Mark Mandell]

There appears to be something of a misconception operating here which is that CBN wheels are for "grinding" a tool's profile, they aren't. They are for "sharpening" an edge. Just because they are mounted on a grinder does not change their nature.

This is more than a semantic distinction. In the broadest sense, anything that uses abrasive to remove metal is grinding, whether with a 40 grit wheel or a 4000 grit waterstone honing slip. For a turner, any rotating abrasive wheel in under 100 grit works well for shaping the cutting profile of a tool. Some professional turners I've met prefer a fresh 80-grit edge and opine that the edge produced cuts wood fibers well enough to start sanding with 220 papers; others prefer to hone to a polished edge as do wood carvers. CBN wheels in the higher grits will serve to bridge the divide between the two "schools" when working with the harder alloy steels as a light touch, a kiss if you will, on a 180 CBN will freshen the tool's edge, removing very little metal, taking 15 seconds to do. A quick swipe on the inside flute with a fine abrasive like a carver's slip will remove any wire edge and provide a micro back bevel for the freshly sharpened edge.

The point here is time away from the lathe. People who turn for a living know that spending 5 minutes first grinding and then honing a tool's cutting edge is a waste of 4 minutes. It may be philosophically satisfying to know your tool has been "ground" like a surgeon's scalpel, but once you start sanding the wood surface with anything less than 2000 grit paper, the distinction is lost.

CBN wheels, when properly used for sharpening high alloy steels, will "wear in" but should never wear out. They are not, however, used to replace a good quality matrix wheel for shaping a tool's profile. Both wheels have a place in a woodturner's shop provided they are used for their strengths.

BTW: Diamond wheels should not be used on tooling other than carbide cutters. Just as a CBN wheel will be ruined by contamination if used on anything less that M2 HSS, even V15 and 2060 alloys will smear on a diamond wheel rendering it worthless for sharpening carbide.

 

[Sergio Villa]

The point here is time away from the lathe. People who turn for a living know that spending 5 minutes first grinding and then honing a tool's cutting edge is a waste of 4 minutes.

...a waste of four minutes....man, what a life!

How many people here (or there) turn "for a living"? I bet very few. The majority turn for pleaure, fan, relaxation, express their desire to make beautiful and/or utility objects and eventually make some mony perhaps to cover the expenses. Satisfaction of a well don object is what count for many, I believe.

PS: even the few that "turn for a living" in reality make or hope to make their money teaching, selling tools often reinventing the same thing many times, trying to sell DVD, and other gadgets to the majority of people who turns for pleasure.

 

[Mark Mandell]

please

...a waste of four minutes....man, what a life!

How many people here (or there) turn "for a living"? I bet very few. The majority turn for pleaure, fan, relaxation, express their desire to make beautiful and/or utility objects and eventually make some mony perhaps to cover the expenses. Satisfaction of a well don object is what count for many, I believe.

PS: even the few that "turn for a living" in reality make or hope to make their money teaching, selling tools often reinventing the same thing many times, trying to sell DVD, and other gadgets to the majority of people who turns for pleasure.

Sergio, by all means, if you wish to spend your time in the shop honing and polishing your tools, please feel free to do so. Likewise, if you believe that putting a gleaming razor-sharp edge on your gouge will make you a better turner or improve the "final result" of what you do on the lathe, go for it,Dude, and may the Force be with you!!!

 

[robo hippy]

"One point that is particularly valid.....in my belief......is the CBN, or diamond, will wear, and a matrix wheel will cut as well when it's worn down, as when it was new.......I think that is an important thought, but maybe not so much for someone who doesn't turn frequently.......When the latter is the case, then the CBN might last a lifetime."

Odie, I think this is a misconception. My 80 grit CBN wheel does not cut as fast as it did when brand new. They do break in a lot over the first month or 4 depending on how much you use them. Since then, it's cutting ability has not diminished at all, and it still will cut faster than a standard 80 grit wheel. The 180 grit wheel cuts much faster than a 120 grit standard wheel when new, and still cuts faster now that it is broken in. They soften up to a point, and then stop. The boron abrasives will take far more abuse than any other wheel. This is why you never have to dress these wheels. I am thinking that it will be a long race to see who dies first, me or my CBN wheels. You will be surprised if you take one for a spin.

robo hippy

 

[Bart Leetch]

"I didn't expect I wouldn't see any disagreement. I don't own any Easywood tools either, so does this mean I can't have a valid opinion about them, either? Saying you disagree is one thing, but let's introduce a little more conceptual thinking to the mix, ok?"

Ok some conceptual thinking.
Said in a gentle quiet voice.

So you have a bad heart I think we can take care of that by replacing it with this mechanical heart.

What kind of testing have you done & is there anything that compares to it in actual use Hands on if you please & if so how does it compare?

We don't have anything to compare it to we just believe it works.

What experience & success rate have you had with this mechanical heart doctor?

Well we've never actually used one before but we're pretty sure it will save your life.

What is you own experience in the field of heart surgery & mechanical heart replacement Doctor?

Oh I don't have any experience in heart surgery & mechanical heart replacement I'm a plumber.

But I did read about this heart on the internet & that's why I believe it will work.