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time for a better sharpening system

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Well, a couple of things here. For me, a finer grit wheel probably will produce a finer burr, as in smaller, and more delicate. I still prefer the burr from the 80 grit CBN wheels. It just works better for general use. I would consider a finer grit burr for the really hard and dense woods, but not for most of what I turn. Just not practical, or efficient, and with little to no real advantages. It might be interesting to see the CBN burrs under a micro scope photo, a new wheel, and a broken in one.

I did exchange a couple of e-mails with Allan about burrs and CBN wheels, and if I remember, he does not use a CBN wheel.

Honing does make for a finer/sharper edge, but the question I have is does it really cut better for long enough to make it worth while. I have done minimal sharpening on the Tormek, and found no advantages.

robo hippy
 
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(Quoting Lacer) Simply polishing the top of the tools prior to raising a burr by grinding improves the resulting cut surface dramatically. This also may suggest that a finer grind might also improve burr quality.

An article in Woodturning compared results of dry and wet sharpening for skews and gouges. The author, Robbie Farrance, concluded tools sharpened with a wet grinder (Tormek) were sharper, produced a better surface, and lasted longer than tools sharpened with a dry grinder. http://www.tormek.com/en/leaflet/pdf/wet_or_dry_en.pdf

Apples and oranges, it would seem. One speaks of scrapers, normally used at high pitch angles with large sharpness angles, one of gouges and skews, normally low in presentation and narrow in sharpness angle.

I think the angle that really counts is the skew angle. Broad into the rotation would put the greatest strain on the edge. As the remaining grinding irregularities are broken away, the edge would round - dull - fairly rapidly. Narrower - a shear - would keep a better edge. It would last longer still if it began honed to a finer state.
 

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Scraping by ...

For those who are familiar with cabinet scrapers, and how to draw/turn/roll (terminology depends on which "expert" you talk to) a burr, that is essentially the same thing that I do with my woodturning scrapers. The resulting burr is very strong and long lasting, but it does take some learning to do it right. I use an oval burnishing tool, but any polished steel rod that is harder than the tool being sharpened will do. I think that the tendency for someone first learning is to apply excessive force and cause the burr to roll into a curl. If that happens, it is necessary to start over. It is also possible to create a burr that is far too agressive -- I know, because I have done it far too often. The cure is usually to not use an angle that is more acute than about 75° and/or lighten up with the burnishing tool. BTW, the edge needs to be smooth and sharp before the burr is put on the edge. It is not quite there straight off the bench grinder. Diamond "stones" can be used to get a smooth sharp edge (I use a Tormek, but I still need to remove the wire edge with a diamond hone before putting a burr on the edge. Be careful that the burr is not work hardened. Done properly, a single pass is needed to put a burr on the scraper. Trying to fine-tune it will just result in a weaker burr.

Most of the woodturners who I know call the crumbled metal swarf that results from dry grinding as a burr. At first casual glance it sort of looks like a burr, but its useful life is so brief that after a very brief period of cutting, "scraping" is truly what it does. It makes more sense to me to create a cutting edge that really does create shavings rather than powder. Too bad that they have to suffer the indignity of being called a "scraper" after getting a "proper" burr. :D
 

john lucas

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Bill I have not rolled a bur on my scrapers in the same fashion I do with my cabinet scrapers. For the cabinet scrapers I run the metal "ticketer" over the edge parallel to the flat side. (usually on both sides for a cabinet scraper). This produces a sort of U on the narrow edge. Then I run the metal across the narrow edge forming a T burr. Then I tilt it 5 degrees or so to form the functional burr. I will try that in a modified way this morning and see how it works on my flat scraper. After honing off the old burr I'll draw the metal across the top, then across the bevel to form the burr. Usually I just hone off the old burr and draw the metal across the bevel at the angle I want. I wonder if drawing the metal across the top first will improve the burr.
 

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John,
veritas makes a gizmo that has a pivot point and some hard angled insert for rolling a burr on a turning scraper much like a cabinet scraper.

I know a few folks who swear by these. Most folks strike a burr with a slip stone or a diamond hone.
A few folks even use cabinet scrapers on their turnings while on the lathe.

I suspect the rolled burr does a nicer job but is the difference noticeable on our native hardwoods?
 

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Bill I have not rolled a bur on my scrapers in the same fashion I do with my cabinet scrapers. For the cabinet scrapers I run the metal "ticketer" over the edge parallel to the flat side. (usually on both sides for a cabinet scraper). This produces a sort of U on the narrow edge. Then I run the metal across the narrow edge forming a T burr. Then I tilt it 5 degrees or so to form the functional burr. I will try that in a modified way this morning and see how it works on my flat scraper. After honing off the old burr I'll draw the metal across the top, then across the bevel to form the burr. Usually I just hone off the old burr and draw the metal across the bevel at the angle I want. I wonder if drawing the metal across the top first will improve the burr.

John, I only recently began doing it the way that it is done on a cabinet scraper. Before that, I did it the way that is more common of just running the burnishing tool across the beveled edge and tilted about five degrees or so, eyeball estimate. I can't say for sure that doing it like a cabinet scraper makes it last longer, but the one advantage I see is that it creates a slightly smaller "flat" on the bevel. This means removing less metal when regrinding the bevel to prep it for a new burr.
 
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The turned edge of a cabinet scraper makes it into a low angle plane with a REALLY close chipbreaker. I have the Veritas variable angle burnisher, and I keep some scrapers with minimum turned and some with heavily turned edges. Minimum makes a nice surface, while heavier is better at dried glue and leveling a bit of misalignment in wide glueups.

I find the common gooseneck curved scraper useful on static bowls, used from rim to bottom on inside endgrain, or branching round downhill into those areas where a gouge can give uphill tearout. The Veritas spoon scraper is also useful for small pickup areas, and for removing the button left after parting.
http://www.leevalley.com/US/wood/page.aspx?p=32641&cat=1,310,41069

The gooseneck almost demands the burnisher device to get an accurate, predictable turn. http://www.leevalley.com/US/wood/page.aspx?p=32633&cat=1,310,41070 Since it's a three-hand job, I recommend you keep the piece mounted in the chuck as you scrape.
 
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I am puzzled by those who insist that the wire burr from dry grinding is gone in seconds. Maybe the difference between the CBN wheel burr and the Al O wheel burr is huge. I can hog out several 10 inch bowls with my scrapers and they still cut fine, and this is with standard HSS.

If I want a good burnished burr on my scrapers, I first hone off the old burr, then touch up the face on the wheel. Some times I will hone off the burr from the grinder, some times not. I haven't noticed that it makes any difference. I do burnish the top of the scraper, about 5 degrees off the flat, then burnish the face, again, maybe 5 degrees off the bevel angle. I prefer the triangle burnishers. How much of a burr you get is determined by how hard you apply the burnishing tool, and you can get a bigger burr if you take several passes over the surface. The problem most have with the Veritas burnisher, is that they think they really have to armstrong the tool against the burnishing rod. It takes little pressure to raise the burr, and if you push too hard, the burr actually rolls over the top, kind of like a wave breaking. This type of burr can be either very/almost too aggressive, or make it so that you really have to raise the handle to get the thing to cut, which is a pain.

robo hippy
 

Bill Boehme

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..... I can hog out several 10 inch bowls with my scrapers and they still cut fine, and this is with standard HSS.

OK, I've also done that, but was afraid to admit it. There seems to be some sort of stigma attached to doing anything other than cleaning up a surface with a scraper.

I mostly use the scraper to refine the curve on the inside of a bowl because for some reason, I can't get a perfectly smooth curve from rim to bottom with a bowl gouge. I took a class from Stewart Batty a few years ago and was in awe of his skill in getting a wonderfully smooth curve in one fluid pass. When he was helping guide my movements I did sort of OK, but otherwise I spend a lot of time getting rid of waves and other noticeable discontinuities near the bottom. They are not always obvious until a gloss finish is applied. Sandpaper is also my friend.

..... The problem most have with the Veritas burnisher, is that they think they really have to armstrong the tool against the burnishing rod. It takes little pressure to raise the burr, and if you push too hard, the burr actually rolls over the top, kind of like a wave breaking...

It is not easy to convey the amount of force to use. When I took a class with Alan Lacer, everybody was asking about the amount of force to apply when creating the burr on a scraper. Words like "light" or "not very much" didn't seem quite adequate, but his suggestion to keep practicing until you get it right is probably about as good as any answer.
 
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It really takes little force to raise a burr. Take a light pass, and feel with your thumb at a right angle to the burr, not parallel as you will slice yourself. If you can feel any burr at all, you can cut with it. I heard one demonstrator claim flat out that it was impossible to raise a burr on a scraper by hand burnishing it. I found out the opposite, and it takes very light pressure. I have no way to figure out pounds per square inch amounts, but considering the small surface of the scraper edge, and the small surface of the burnisher, I would imagine that it could approach hundreds or maybe even thousands of psi if you lean on it.

robo hippy
 
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Grinder opinion

The Woodcraft grinder is well worth it, in my opinion. Also, using the new metal wheels is also a pleasure. The whole rig runs very smoothly and I am quite pleased after upgrading from a wilton grinder that always seemed to be running "bumpy"...as if the shaft were slightly bent. The wobble was not fun. All is much better now.
Sometimes Woodcraft has the slow grinder on sale for about $100, so keep your eyes open.
 

Bill Boehme

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It really takes little force to raise a burr. Take a light pass, and feel with your thumb at a right angle to the burr, not parallel as you will slice yourself.....

Indeed yes. I have accidentally cut myself on a scraper when doing things like tidying up the shop. My safety awareness is up when turning, but then when not actually doing woodworking or turning I have forgotten on more than one occasion that tools can still cut even during their time off.

I would say that it takes very little force, but a lot of pressure to raise a burr, however, I am sure that saying something like that would serve no useful purpose.
 
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To answer the o.p.'s question, no, you don't need to change anything about your sharpening system. There are thousands of turners getting great results from the same setup you have. You might need a new wheel, a picture would allow us to confirm that. As you read through this thread you will notice that there are variations on how to sharpen, and what people call sharp. For my money, an 80 grit wheel, and honing if the grain is not straight suits me. I don't like the jig you use, but thats me. I have a student who made a jig so he could sharpen his tools on a platten sharpener. All of his tools are done to a minimum of 8000 grit, and skews to 16000. You can see a clear reflection in his bevels. He and I both start sanding at the same grits. I think his tools stay sharper longer, but he does assure me that my trip to the grinder is much shorter than his sharpening exercise. My 1745 rpm grinder is quiet and smooth, cheap ones generally are not.
 
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If I were going to upgrade to a better grinder, I would also get the CBN wheel from D-way..........I got the 180 grit, and it puts a super edge on my lathe tools and no dust or replacement as the wheel stays the same diameter.......basically a wheel that will last for years and years for the average user!
 
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Wow thanks for all the replys today I get a new slow speed grinder from wood craft and I just got word that the rest of the accesories from wolverine have arrived. the bad news when you live in Northern Ontario I have 3 hours of driving to go pick them up.
 

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I had the opportunity to try out a CBN sharpening wheel at SWAT this weekend and there is a world of difference between them and traditional wheels -- smooth running, quiet, clean sharp edge, and very little heat. The one that I tried also had CBN abrasive on the side of the wheel.
 
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I had the opportunity to try out a CBN sharpening wheel at SWAT this weekend and there is a world of difference between them and traditional wheels -- smooth running, quiet, clean sharp edge, and very little heat. The one that I tried also had CBN abrasive on the side of the wheel.
That is the Optigrind. http://www.optigrind.com/

I have a 6" one on my portable grinder. Very good.
 
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Harder steel

How do the CBN wheels hold up and work on the Thompson tools? The ad on the links says good for HSS but doesn't mention the harder steel.
 
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Mark,
I've had my CBN for about a year 80 and 180 on a Delta single slow speed, I use Doug's Gouges almost exclusively and I don't see any wear pattern in the wheels. I use the 80 grit about 90% of the time. I have tried and own a large collection of sharpening systems and this is by far my favorite. I like it even better than my 2hp belt grinder with a 8" or 10" contact wheel with 220 grit belt. Does a great job on the kitchen knives though. I even took my grinder with me a few weeks ago when I took a class from Doug Fisher. I have never been impressed with the provided wheels at the two art schools I have been too. Now I've only had it a year so...Long term, I don't have personal experience, I did talk with Dave at D-way about this very issue before I purchased my wheels and I feel confident I'll be happy with them in the long term. One other thing these wheels are 1 1/2' wide and while that doesn't seem like much different than the 1" wheels it is, much easier and Don Geiger is coming out with a new jig that will make putting multiple bevels very easy and repeatable. No I don't get anything from Dave, Doug or Don. Triple D...sounds like the food network.
 

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Mark If I remember correctly Doug told me his tools are hardened to 93 Rockewll so just about any grinder will sharpen them.
 

odie

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Sometimes "thinking" just gets me into trouble, but......

I don't have, nor have ever tried a CBN wheel, so my thoughts are strictly theoretical.......

It seems to me that if honing is being done, the method of metal removal is secondary to this final step, because the cutting edge itself is the working part of the tool.

So......can it be assumed those who are using a CBN wheel (80 or 180), are not honing, and are going direct to the lathe from the CBN wheel? Are any of these CBN users using a slipstone, or diamond cone on the upper edge of the grind only?

Truthfully, it doesn't make a lot of sense to me to expect 80, or 180 grit wheel, no matter what the composition of that wheel is, to produce a cutting edge as sharp as honing with a 600 grit diamond, both top and bottom of the edge.

Since I don't have the CBN wheel, nor do I have access to one, I can't do a simple experiment of testing the edges on a single piece of wood mounted on the lathe.......all other things being exactly the same. That seems like the only way to see if the edge directly from a CBN wheel cuts as well as a tool that has a finely sculpted edge from a diamond hone.......does it not?

ooc
 
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Bill Boehme

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.....So......can it be assumed those who are using a CBN wheel (80 or 180), are not honing, and are going direct to the lathe from the CBN wheel? Are any of these CBN users using a slipstone, or diamond cone on the upper edge of the grind only?

Truthfully, it doesn't make a lot of sense to me to expect 80, or 180 grit wheel, no matter what the composition of that wheel is, to produce a cutting edge as sharp as honing with a 600 grit diamond, both top and bottom of the edge.

Since I don't have the CBN wheel, nor do I have access to one, I can't do a simple experiment of testing the edges on a single piece of wood mounted on the lathe.......all other things being exactly the same. That seems like the only way to see if the edge directly from a CBN wheel cuts as well as a tool that has a finely sculpted edge from a diamond hone.......does it not?

ooc

Odie, I only tried out the CBN wheel for a minute or so, but here is my observation:
Initially, I noticed the very wide smooth surface of the wheels and nice level distribution of grit. When I started grinding a skew, I noticed the sound was much different from using a grinding stone -- it was smooth with none of the rattling sound of a stone. Also, I could not feel any vibration in the tool -- very uncharacteristic of sharpening on a grinder. Finally, There was no trail of sparks so typical of grinders -- well, actually, when I looked really hard, I could see a very faint trail of metal.

As far as going directly from the CBN wheel to turning without honing, I think the reason has to do with the absolute flatness of the CBN wheel compared to other sharpen stones. A typical stone is not very flat -- even after being cleaned and dressed it has ridges and valleys. Even though I was using an 80 grit wheel, the surface texture didn't bear any resemblance to the texture of an 80 grit sharpening stone. Because of this, the bevel that I ground while not quite as polished as an edge produced on a Tormek, was a fairly reasonable facsimile. And, the bevel was barely warm -- I didn't bear down on the tool while sharpening -- i was very gentle with the tool and took my time, but still I was a bit surprised about this.

The OptiGrind wheels have a one-inch hole and then they have large adapter bushings to fit them to whatever grinder shaft size needed. OptiGrind is European, but available on this side of the pond since I noticed them advertized in Woodturning Design.

The only problem that I had was a language barrier -- the nice young lady at the booth was from the UK so she was speaking the Queens English and I was speaking Texan. I managed to gather that the OptiGrind wheels were going for something in the vicinity of $180+ so I think that I will stay with my Tormek for the time being.
 

odie

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Odie, I only tried out the CBN wheel for a minute or so, but here is my observation:
Initially, I noticed the very wide smooth surface of the wheels and nice level distribution of grit. When I started grinding a skew, I noticed the sound was much different from using a grinding stone -- it was smooth with none of the rattling sound of a stone. Also, I could not feel any vibration in the tool -- very uncharacteristic of sharpening on a grinder. Finally, There was no trail of sparks so typical of grinders -- well, actually, when I looked really hard, I could see a very faint trail of metal.

As far as going directly from the CBN wheel to turning without honing, I think the reason has to do with the absolute flatness of the CBN wheel compared to other sharpen stones. A typical stone is not very flat -- even after being cleaned and dressed it has ridges and valleys. Even though I was using an 80 grit wheel, the surface texture didn't bear any resemblance to the texture of an 80 grit sharpening stone. Because of this, the bevel that I ground while not quite as polished as an edge produced on a Tormek, was a fairly reasonable facsimile. And, the bevel was barely warm -- I didn't bear down on the tool while sharpening -- i was very gentle with the tool and took my time, but still I was a bit surprised about this.

The OptiGrind wheels have a one-inch hole and then they have large adapter bushings to fit them to whatever grinder shaft size needed. OptiGrind is European, but available on this side of the pond since I noticed them advertized in Woodturning Design.

The only problem that I had was a language barrier -- the nice young lady at the booth was from the UK so she was speaking the Queens English and I was speaking Texan. I managed to gather that the OptiGrind wheels were going for something in the vicinity of $180+ so I think that I will stay with my Tormek for the time being.

Howdy Bill......

You do realize, of course, there is absolutely no vibration when honing by hand with a diamond hone.....:D

If the Optigrind is running smoother, I can see where it would have an advantage over a conventional wheel of the same grit, but in the end we are talking about the difference between 600 grit and 80/180 grit. If the vibration, or smoother function were the factors that lead to the creation a sharp edge, then there would be no reason for various degrees of fine grits available to those who hand sharpen other types of tools.

It's really difficult for me to grasp the concept that the fineness of grits has no bearing on how sharp it is........Maybe someday, I can do the test I mentioned, and have a practical first-hand example for comparison between the two. That would be conclusive, but in the mean time, the diamond hones are giving me the kind of performance that count, and are demonstrable through result.



ooc
 
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As far as going directly from the CBN wheel to turning without honing, I think the reason has to do with the absolute flatness of the CBN wheel compared to other sharpen stones. A typical stone is not very flat -- even after being cleaned and dressed it has ridges and valleys. Even though I was using an 80 grit wheel, the surface texture didn't bear any resemblance to the texture of an 80 grit sharpening stone. Because of this, the bevel that I ground while not quite as polished as an edge produced on a Tormek, was a fairly reasonable facsimile. And, the bevel was barely warm -- I didn't bear down on the tool while sharpening -- i was very gentle with the tool and took my time, but still I was a bit surprised about this.

Flat counts on non-gouges. For a gouge, you'd have to have a coved stone to get more than one point (line) in contact. Always makes me snicker a bit when people talk about spending grit to get a flat stone so they can grind their gouges. I keep my wheels fairly flat by using the high spots preferentially. Makes them last a lot longer as well.

Why would you be astonished to find that an 80 grit had a lower coefficient of friction than a 150?
 
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I’ve had a D-Way CBN wheel for a few months now and here are my initial impressions.
First, it’s a well machined and balanced steel wheel with a matching set of bushings. This alone is enough to solve about 98% of the vibration and truing issues found with typical plastic bushings found on most traditional wheels. This also may extend the life of your grinder, due to less vibration
Next is its width. Being wider helps in many ways giving the freehand sharpener more room to roll the tool before coming to the edge and making it easier to sharpen larger tools, like skews are just a couple.
The D-Way wheel I own does not have abrasive on the side like the Optigrind mentioned earlier in this thread. That’s my personal choice, if a tool does slip off, there is nothing to catch on the side of the wheel..
The next thing is that the diameter will remain constant. I think this makes it easier to set up jigs and fixtures as well as giving you a much higher level of consistency.
Flatness, it stays flat, there are no ridges or valleys to deal with, again adding to an overall better result.
Clogging, it does not clog, therefore, no need for cleaning or dressing.
It’s cleaner since it does not wear like a traditional wheel, throwing dust as it wears away.. I simply placed a magnet below the wheel to catch the filings.
The wheel cuts cleanly and smoothly, requiring very little pressure and time to achieve a sharp edge..
Obviously I’m happy with my purchase, I only wish I bought one sooner.

I’m not sure where this notion of not needing or wanting to hone if you use a CBN wheel came from. I think it’s a choice like anything else. How sharp is sharp enough for you?
JMHO
 
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I have the D Way, Optigrind, and Cuttermaster (advertised in AAW magazine) wheels. There is little difference in the quality of the wheels, but if there is any, the edge goes to Cuttermaster because their wheels are made to sharpen the milling bits for the CNC machines. These wheels will cut and grind metal from hardened Carbon steel, like our bench chisels and any of the HSS and cryo steels that we use in woodturning. They do not do well with softer carbon steel wheels or non magnetic metals like some stainless, aluminum, brass, copper, etc. You can touch up Carbide, but diamond is much better for that, and I would not use it for carbide. I have also sharpened tantung steel on it as well with no loading problems. You can hone or not, just like standard Al O wheels. CBN is as far above standard wheels as 3 phase converted variable speed lathes are above treadle lathes.

robo hippy
 

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I’m not sure where this notion of not needing or wanting to hone if you use a CBN wheel came from. I think it’s a choice like anything else. How sharp is sharp enough for you?
JMHO

Hi Ed........

Actually, there are quite a few turners who don't hone......not just with CBN wheels, but with other types of grinding wheels and methods, as well.

Your question "How sharp is sharp enough for you?" is a KEY question to consider. Sharper tools cut cleaner than less sharp tools.....but, they need regular maintenance to keep them sharp. This seems to be the main issue, or division between both camps. This is because many turners don't think it's worth the effort to hone and re-hone often, when the super sharp edge only lasts a short while. After all, one can sand their way to a great finish, regardless of the quality of the surface finish they get directly from the tool.

As you say, and you are absolutely correct, it certainly is a choice, or "fork in the road", if you will....... The distinct, and very powerful advantage to getting the best tool finish you can just prior to sanding, is you simply sand less and start at a much higher grit. The less sanding you do, the more true and circular your bowl will be. (Sanding ALWAYS removes more wood from the long grain, than it does with end grain. The same is true for softer and harder irregular grain patterns, grain like ash, burl, uneven spalting, etc.)

Think about this: If you want nice clean, sharp, even corners between one surface and another, and you want detail grooves that don't get wide and narrow, deep and shallow over the full circumference of your turning........Then it is NECESSARY to start with a tool finish that requires the least amount of sanding.

(Common sense, eh? :D)

ooc
 
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Bill Boehme

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... Why would you be astonished to find that an 80 grit had a lower coefficient of friction than a 150?

I'm not sure if the question was directed towards me or someone else. I didn't mention anything connected to your question and if someone else did, I must have missed it.

Actually, there are quite a few turners who don't hone......not just with CBN wheels, but with other types of grinding wheels and methods, as well. ...... If you want nice clean, sharp, even corners between one surface and another, and you want detail grooves that don't get wide and narrow, deep and shallow over the full circumference of your turning........Then it is NECESSARY to start with a tool finish that requires the least amount of sanding....

I agree fully with your observation.

My one minute of playing with the OptiGrind CBN wheel was interesting, but not something that I felt compelled to get.
 
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The less sanding you do, the more true and circular your bowl will be. (Sanding ALWAYS removes more wood from the long grain, than it does with end grain. The same is true for softer and harder irregular grain patterns, grain like ash, burl, uneven spalting, etc.)

Think about this: If you want nice clean, sharp, even corners between one surface and another, and you want detail grooves that don't get wide and narrow, deep and shallow over the full circumference of your turning........Then it is NECESSARY to start with a tool finish that requires the least amount of sanding.

(Common sense, eh? :D)

Well, once again, surface depends more on presentation than preparation of the edge. Back to that blade whose keenness you verify by palpating across the edge, because you'd be diving for the bandaids if you slid your finger along it.

There are also ways of sanding which do not depend on forcing the paper into the piece. Support the sander on the rest, as you do with other tools, and let the work come to it. Not only will you avoid the end/face grain differential, but you will not plunge into soft spots. If you get things round by letting them rotate against a fixed tool, doesn't make a lot of difference whether that tool is slicing, scraping, or sanding.

Common sense.

You won't have to be surprised it takes less pressure to warm the paper with 120 than with 80, either.
 

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Well, once again, surface depends more on presentation than preparation of the edge. Back to that blade whose keenness you verify by palpating across the edge, because you'd be diving for the bandaids if you slid your finger along it.

There are also ways of sanding which do not depend on forcing the paper into the piece. Support the sander on the rest, as you do with other tools, and let the work come to it. Not only will you avoid the end/face grain differential, but you will not plunge into soft spots. If you get things round by letting them rotate against a fixed tool, doesn't make a lot of difference whether that tool is slicing, scraping, or sanding.

Common sense.

You won't have to be surprised it takes less pressure to warm the paper with 120 than with 80, either.

You are almost right, MM!.........:D

Surface preparation is the combination of the two.

Sharp edge plus proper use of tools will result in the best surface preparation. I guess I thought that would have been a given, and most people here would have that figured out......without the need to mention that tool control was also part of the equation........

Correct about the sanding. There too, it is something that gets better with experience. (.....AND, if you don't have sharp tools, you are going to get A LOT of experience sanding! Heh,heh,heh! ;))

ooc
 
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You are almost right, MM!.........:D

Surface preparation is the combination of the two.

Sharp edge plus proper use of tools will result in the best surface preparation. I guess I thought that would have been a given, and most people here would have that figured out......without the need to mention that tool control was also part of the equation........

Hmmmmm. It's preparation and presentation of the edge, grammatically. Guess you didn't figure that out? Which means you missed the point that, of the two, edge presentation trumps edge preparation in production of a good surface. Explains why people can grind with an 80 grit and cut to a 220 grit ready surface. Proper presentation also means less resistance, which translates to better tool control. Point of agreement.
 
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