CBN Grinding Wheels

[Bill Boehme]

Too cold to go outside, still looking at metals.

Where I can get prices without requesting a quote and dealing with salespeople CPM-15V is 67% higher priced than CPM-10V. It also offers almost twice the wearability so 15V is actually cheaper over the life of the tool. When it comes to shaping or sharpening the alloys, both fall around 30-35% of the machinability of 1% carbon steel which I assume is mild steel. The people that make it say to use CBN or a special ceramic aluminum oxide to shape or sharpen it. I couldn't find the SG wheels to fit standard bench grinders, perhaps a seven inch wheel, no real information. However, using any of the more common aluminum oxides flattens the grit on the wheel or belt and is not the preferred method of sharpening 10V or 15V per the maker.

I haven't looked for other sources but a bit of trivia or maybe something useful to someone that frequents gun shows and such, stellite is used for some machine gun barrels. I think it gives about fifteen times the life of a standard barrel at about fifteen times the cost. A wash in terms of life but saves a lot of labor and of course the barrel doesn't fail in combat. One barrel would be a lifetime supply of stellite, might cut with a water cutter but I don't know.

It is interesting to explore all of this, I even found the steps of how CPM is made. In the end I think the KISS rule applies for me though and quality M-2 may indeed be better than the 10V with the sharpening equipment I have. I think I will still buy CPM when I can, when I get enough tools I'll have to upgrade to CBN wheels!

Hu

Fifteen times the cost for a stellite barrel might possibly mean fifteen times the total cost if it includes labor.

When comparing 10V to 15V, technical data often doesn't translate into discernible differences under real world conditions where things can't be so clearly defined as they are in a controlled test.

When the 15V tools first came out, I asked a person whose initials are D.T. at the SWAT symposium what the big deal was about 15V as compared to 10V since the 15V tools were quite a bit more expensive. He said something to the effect that the 10V tools were more than adequate when doing a cost vs. performance comparison. And, that's all that I'm going to say about that. Talk to D.T. if you want to know more.

FWIW, my favorite bowl gouge is a Sorby half-inch M2 gouge. It has a flute that is highly polished with no milling marks and is a bit more V shaped than the Crown M4 PM bowl gouges. It seems to go a bit longer than the Crown tools between sharpenings, but that is very subjective and not based on any sort of honest testing.

Another favorite of mine for removing lots of wood fast is my ¾" Henry Taylor Kryo bowl gouge. I have it ground with steep wings and about 45° nose angle. It does a great job of holding its edge.

I have four Thompson bowl gouges plus several other Thompson tools. The bowl gouges are nice and hold an edge well, but I don't care for the stair-step milling marks in the flute. D.T. says that they aren't any rougher than any other brand, but that simply is not true. If I were sharpening them on a 43 grit AO wheel maybe I wouldn't mind the the jagged cutting edge, but when using my Tormek to create a final finishing edge, there is a scratch pattern left on the wood. The same issue might exist with a 400 grit grit CBN wheel to create a polished bevel. The resulting sawtooth cutting edge is only a problem if I am working on wood that doesn't sand well because of variation in grain hardness. or if it is punky.

 

[Gerald Lawrence]

Too cold to go outside, still looking at metals.

Where I can get prices without requesting a quote and dealing with salespeople
Hu

I found this on a Facebook forum last night. You can get prices (if you know what you are looking for) in both bulk and singles.
http://www.onlinemetals.com/

Is a very interesting site. Thought I had another site, but cannot find it. That may be Grainger.

 

[john lucas]

Hu check this out. It was posted on Woodcentral.
http://www.et.byu.edu/~sorensen/TMS 2007 D2 Processing.pdf

 

[James Seyfried]

Too cold to go outside, still looking at metals.

Hu

And you live where? I was outside yesterday looking at some cold rolled steel and enjoying the sunshine.

 

[Bill Boehme]

And you live where? I was outside yesterday looking at some cold rolled steel and enjoying the sunshine.

View attachment 8235

It looks like you were sitting on some cold rolling steel.

I lived about half my life on the Gulf coast and have spent a couple winters in central Kansas as well as many ski trips to Colorado and New Mexico. The high humidity bone chilling cold along the coast always felt much colder than the much dryer climate even though the actual temperature wasn't as cold. When the RH is hovering around the dew point insulation seems to lose its effectiveness.

 

[Gretch Flo]

And you live where? I was outside yesterday looking at some cold rolled steel and enjoying the sunshine.

View attachment 8235

JIm-I was too busy trying to figure out why I had no water coming out in my tub. Heated the upstairs to 77 and basement to 70 yesterday (just a couple of deg from what it had been inside in the past several days) and finally after 24 hours I had water. Two or 3 outside spigots are still frozen. -14 2 days ago, and maybe -16 tomorrow night. Put 3 large bk plastic bags of shavings around each of those spigots today.
Bill, can I come and visit???? Brrrrrrr, Gretch

 

[Bill Boehme]

\.... Bill, can I come and visit???? Brrrrrrr, Gretch

It's pretty cold here in north Texas. I actually had to put on a long sleeve shirt this morning. We have been having T-shirt weather lately. It's about time for everything to start greening up which will next be followed by a hard freeze. Normally, I would already have the potatoes in the ground, but the weather has been colder than normal.

 

[robo hippy]

Pleasant here, I went out and planted my sun flower forest today..... I will have many happy squirrels, birds and bees again this summer.

robo hippy

 

[hockenbery]

Cold here by our norms. Mid 60s. Today. We covered plants and brought the orchids inside.
Might get to 32-30 tonight. And maybe as low as 25 tomorrow night.
Forecast high of 55 tomorrow. Brrrrrr !

Be in the 70s Saturday

 

[robo hippy]

My brother Paul, might even be wearing shoes down there. He lives in Lorida. Had some clips up of his soft shelled turtles and brown bull heads feeding in his pond.... I need to make it down there some time for the gator hatching. Help them little suckers out of their shells...

robo hippy

 

[john lucas]

Just stuck my head out the door. -3 That's the coldest it's been here in Tenn in about 20 years. I remember it was -11 about that long ago and i slept in a tent in my front yard testing out a sleeping bag that was supposed to go to -25. It worked. I also went out and photographed at Fall Creek Falls state park that day. They had 60 foot icycles that on the cliffs. They started falling and exploding like grenades when they hit the rocks below. We decided to leave after I got a busted lip and my friend got a bloody nose. Glad I'm heading to Pennsicola this morning to warm up. Doing a Demo there Saturday.

 

[Gretch Flo]

Just stuck my head out the door. -3 That's the coldest it's been here in Tenn in about 20 years. I remember it was -11 about that long ago and i slept in a tent in my front yard testing out a sleeping bag that was supposed to go to -25. It worked. I also went out and photographed at Fall Creek Falls state park that day. They had 60 foot icycles that on the cliffs. They started falling and exploding like grenades when they hit the rocks below. We decided to leave after I got a busted lip and my friend got a bloody nose. Glad I'm heading to Pennsicola this morning to warm up. Doing a Demo there Saturday.

-10 this am. My 3 thermometers are all incorrect-not used to this cold. Tonite to be -14. Wind chill -25. Many schools closed. Wood stove keeping the living room a toasty 73. In 9 days I go to annual orthopedic meeting in Sun Valley Id. They have been having 45-50 degree weather and skiing terrible. Predictions are cooler when I am there and not so good for the fly fishing I intend to do (hi's in the lo 30"s) Gretch

 

[Mark Hepburn]

Bill,

From time doing a lot of metal fabrication I hate grit all over me. I hate it more the longer I am away from it too. Makes the CBN have a lot of appeal but I don't have a clue what I really want although the 180 grit all around wheel seems like a fine place to start. I almost had myself talked into the wonder wheel with the radiused sides, side flat grind area, recess, yada, yada. Then I got to thinking, I only flat grind a little once in a blue moon and I'm not using a dovetail chuck, don't know that I ever will.

Slammed the sides of the wallet together after putting the credit card back that was starting to wilt a little from the heat anyway. I remembered back when I bought half a two car garage woodworking shop a couple three years ago there was one of the little one inch belt sanders in there. I don't think either my brother or I have staked a specific claim on it. I'm almost certain one inch belts are cheaper than CBN wheels, especially when I don't know which CBN wheels I want. A close call but I think the buy fever passed me by this time!

Hu

Hey Hu. When you make it down to Houma you can test drive my Dway 180 on that $99 Rikon grinder.

 

[Hu Lowery]

sounds great Mark, apologies to everyone else

Mark,

The main reasons to visit are to drink your coffee and play with your toys!

Sorry guys, minor crisis or three around here, lost track of the thread. I'll do a little catching up but it may be awhile.

I had a handful of specialty metal suppliers bookmarked from old favorites lists, don't know how many are still good though. There were some people called Principle Metals, not sure of the spelling, that had great information on everything.

Hu

 

[Mark Hepburn]

Just stuck my head out the door. -3 That's the coldest it's been here in Tenn in about 20 years. I remember it was -11 about that long ago and i slept in a tent in my front yard testing out a sleeping bag that was supposed to go to -25. It worked. I also went out and photographed at Fall Creek Falls state park that day. They had 60 foot icycles that on the cliffs. They started falling and exploding like grenades when they hit the rocks below. We decided to leave after I got a busted lip and my friend got a bloody nose. Glad I'm heading to Pennsicola this morning to warm up. Doing a Demo there Saturday.

John, you aren't kidding! I drove up to Memphis yesterday with a crew to do a cookout for st. Jude children's hospital. they're opening a new facility and we did a little BBQ for it. Running a bunch of brisket and such on a pit in 17 degree weather is a whole different thing than usual and boy are you lucky to be on the gulf coast!

 

[Mark Wollschlager]

Thanks to Reed for the good article.
I had been running my old woodcraft grinder without guards since the CBN's went on.
Checked the inside guards and saw the screw holes that needed to be ground down.
Cut them down with a cutoff wheel.
Inside guards are re-mounted.
And the 'outlet port' makes a good place for the little box of rare earth magnets to catch grit.

 

[Paul May]

I originally wrote this for Woodturning Design, but right after I submitted it, they folded. It was too long for the AAW Magazine, and I couldn't edit it down far enough for them, so I am posting it on my web site. About 4,000 words. It covers every question I have seen asked on the turning forums.

http://www.robohippy.net/featured-article/

robo hippy

@robo hippy . Hi Reed. I know this is a really old thread but was wondering if this article was still available to read? I am contemplating a CBN wheel for my grinder and would like to know more. Are all wheels of the same grit created equal?
Thanks,
Paul

 

[robo hippy]

Not sure if it is available any more. I dropped my web site not long after I stopped making and selling my grinder and bowl rests. With the wheels, I say if you are getting one, then get a 180 as it will do 90% of all the sharpening you will do. If you get 2, then get a 600. I don't consider the 320 to be enough of a step up. As for quality, I don't really see much difference. I do have almost all D Way tools. They have been friends for a long time. There was some skepticism about the ones where the CBN was bonded onto aluminum, but they have been out for quite a while and I have heard of no issues with them failing. Now, everyone seems to have the wheels for sale. I prefer the 1 hp Rikon to the 1/2 hp Rikon grinders. My other grinders are Baldor, which have a 'real' 3/4 hp motor. Other than that, they may not be the cheap solution, but they are by far the 'best buy' solution. For production work, you will get about 5 years out of them. For most others, many more years than that.

robo hippy

 

[Alan Weinberg]

no way to cut and paste the original article? TIA.

 

[Paul May]

Not sure if it is available any more. I dropped my web site not long after I stopped making and selling my grinder and bowl rests. With the wheels, I say if you are getting one, then get a 180 as it will do 90% of all the sharpening you will do. If you get 2, then get a 600. I don't consider the 320 to be enough of a step up. As for quality, I don't really see much difference. I do have almost all D Way tools. They have been friends for a long time. There was some skepticism about the ones where the CBN was bonded onto aluminum, but they have been out for quite a while and I have heard of no issues with them failing. Now, everyone seems to have the wheels for sale. I prefer the 1 hp Rikon to the 1/2 hp Rikon grinders. My other grinders are Baldor, which have a 'real' 3/4 hp motor. Other than that, they may not be the cheap solution, but they are by far the 'best buy' solution. For production work, you will get about 5 years out of them. For most others, many more years than that.

robo hippy

Thanks so much for the reply Reed. The info helps a lot!

Paul

 

[Bill Blasic]

If all you can afford is the 1/2 HP Rikon you can use it with two CBN wheels. It will take a few seconds longer to reach speed but then there is no difference. The difference on the one I have is that once shut off the Rikon 1/2 HP takes almost 13 minutes to stop. I know there was or is a faction that uses 600 grit to 1000 grit CBN wheels for sharpening and I won't argue that they will get the tool sharper but that sharper tool dulls a lot faster. For me the 180 grit CBN wheel gives me the best balance between sharpness and the length of time it stays sharp. I always keep a grinder with at least 1 white wheel for reshaping.

 

[Gord Cameron]

Bill, I have shared your preference for a 180 wheel and a white wheel (mine a Norton 46X grit) for reshaping, but I recently added a 600 grit because I sharpen frequently and I want to remove less steel each time.

I wonder if it is true that sharper edges dull more quickly. I used to suppose that, but in the knife sharpening field the tests show the opposite: that the sharper edge actually lasts longer, or at least cuts more, presumably because it is encountering less resistance. It seems possible that, in the turning context, the sharper edge would give the impression of dulling faster but it has in fact removed more wood--the real test--in the course of getting there.

Anyway, I am quite liking my 600 grit: with one pass I get a new edge without feeling that I am losing much steel--that lets me feel better about going to the wheel frequently.

 

[john lucas]

We need to clear up 2 definitions. There is a more polished edge (600 grit vs 180 grit). Then there is a more acute edge. 40 degree vs 55 degree. A more acute edge is sharper but the edge may be brittle. A more polished edge will hold an edge longer. This us because it takes longer to wear down the finer ragged edge to what we perceive as dull. There was an article in woodturning magazine out of the UK many years ago with high mag photos to show this. I was doing a production run of spindles when I got my 350 cbn wheel so I did a test sharpening alternatively on the 180 and 350. I could tell the edge lasted longer.

 

[Gord Cameron]

We need to clear up 2 definitions. There is a more polished edge (600 grit vs 180 grit). Then there is a more acute edge. 40 degree vs 55 degree. A more acute edge is sharper but the edge may be brittle. A more polished edge will hold an edge longer. This us because it takes longer to wear down the finer ragged edge to what we perceive as dull. There was an article in woodturning magazine out of the UK many years ago with high mag photos to show this. I was doing a production run of spindles when I got my 350 cbn wheel so I did a test sharpening alternatively on the 180 and 350. I could tell the edge lasted longer.

Very interesting, John. When you say "I could tell the edge lasted longer", do you mean the edge sharpened on the 350 grit lasted longer? If so, would you expect that to be extended with a 600 grit wheel?

 

[Bill Blasic]

I only base what I said on the voices of those who have tried the higher grits and have gone back to the 180 grit wheels. I have never used a higher grit wheel on my tools (although there is a 350 grit CBN on one of the grinders available to others to use in my shop). As far as the 180 grit using up a lot of steel when sharpening I have found that not to be the case. I use the Vector Grind Fixture and take off so little when sharpening that I will never wear out any of my gouges. This because my grinder is only used by me and the setting never changes so there is never any adjustment to the setup and one very light pass sharpens the gouge and about every 3 o 4 sharpenings I use the lower 2 holes of the jig to remove the second and third relief cuts. In reality it is never going to be a one shoe fits all as what one person perceives as sharp is not what another may see as sharp. Each and every one of us must find what works best for them. What we all say are just what works for us and are starting or finishing points.

 

[robo hippy]

I am in the 'coarser lasts longer' school. I do like the 600 grit for finish cuts in punky woods, but other than that, the edge just doesn't seem to hold up as well. There was an 'ultimate' sharpening video up on You Tube by Stumpy Nubbs, and they used those strings you cut and measure the amount of pressure it takes for the string to cut. It seemed to be that no matter the initial sharpness, that wore off pretty quickly, but the sharp part tapered off slowly. To me, that would translate as fresh edge for finish cuts. I would sharpen before any finish cut, and the grit is not the determining factor.

robo hippy