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Sam Murdoch
04-13-2019, 8:24 PM
Hi All,

Have been pondering an upgrade to my sharpening system for some time now. Was pretty set to give Ken an order for some CBN wheels and maybe an 8" grinder too. I have a Tormek 2000 which has been taking up space on my bench for years. it has never been a satisfying tool and so I have been left to sharpen all my edge tools on my Shaptons. Getting time to renew some edges beyond basic sharpening though and my bench stones will make this a long project. The Tormek too makes this a tedious process.

SO - I turn to you guys for some advice.

1) In the interest of saving $$s will simply getting a CBN for the Tormek be a huge and useful upgrade? Downsides?

2) Again, in the interest of saving $$s but also bench space - I would be happy to have a 1/2 HP 8" grinder with 2 mounted wheels but will that prove to be a more useful tool up than simply replacing the Tormek wheel?

3) GRITS - If I buy one wheel (square edge) is there a need to go beyond 220? Will that provide a chisel edge that can be tweaked with stropping or will I want more polish off the grinder?

4) If I go with a 2 wheel set up what might you recommend please. 1 for general purpose edge tools like knives and axes (80 grit?) and 1 for the edge tools -180 or 220 or 350? I really have no idea how these compare to other systems in regards to grits.

Thank you for any advice and real world experience.

Sam

Derek Cohen
04-13-2019, 9:20 PM
Sam, I went down this path some years ago and wrote about it here: http://www.inthewoodshop.com/WoodworkTechniques/UltimateGrindingSharpeningSetUp.html

It is interesting that CBN wheels have been known to turners for decades, yet a revolution for flat woodworkers. When I discovered them, I moved from a Tormek to a 8” half-speed grinder with 80 and 180 grit CBN wheels, and have not gone back to the Tormek. I would consider a CBN or diamond wheel for the Tormek to be a waste as it remains slow, which is inefficient. I like the way the Tormek holds a blade, both for turning chisels and flat blades, and use this system on the dry grinder.

Going finer than 180 grit, which I consider to be a good all-rounder, is not indicated for chisel/plane grinding since you will still need to go to stones for honing. Lathe chisels are often used off the grinder, and 600 upwards is therefore necessary. Keep in mind that the finer the grit, the greater the heat generated. This is not an issue with the M2 of a lathe chisel, but it is a factor with O1 or similar with bench chisels and plane blades. CBN wheels run pretty cool, but it is still possible to create a lot of heat if you do not make good choices or use good technique.

Ken is a great guy to work with. He gets my recommendation.

Regards from Perth

Derek

Frederick Skelly
04-13-2019, 9:44 PM
You can buy a 1/2 hp low speed Rikon grinder for $110 and install a cbn. That's what I did and it's been a great setup. It's fast to reset or change a bevel angle and I finish on my shapton stones. No regrets.
If you want to mount 2 cbn wheels, I think I'd get the 1 hp version for $230. But I havent personally found a need for a second cbn wheel. A single 180 grit wheel works well for me. YMMV.

And after you get the new grinder and cbn, of course you'll want a tormek-style tool holder (BGM100) and maybe a couple accessories you don't already have. At least, that's what happened to me. (Look at Derek's webpage and setup. It was a great help to me.)

Fred

Sam Murdoch
04-13-2019, 10:57 PM
Thank you both. Just the kind of recommendations I was hoping to receive. Derek - you expressed exactly my reservation about buying a wheel for the Tormek "I would consider a CBN or diamond wheel for the Tormek to be a waste as it remains slow, which is inefficient."

Thanks too, Frederick. 1 wheel will be how I will start. Yup, and some accessories.

8" is OK, not too much of a hollow in chisels?

Sam

Phil Mueller
04-14-2019, 6:21 AM
Sam, I went the 8” slow speed grinder with 180 CBN about a year ago (also from Ken). As others have said, it makes rehabing old irons and changing angles a breeze. Hard to tell scale and I’m afraid it’s a little out of focus, but here’s the hollow on a 1” chisel:

407935

John K Jordan
04-14-2019, 7:24 AM
Sam,

I've use a 1200 grit CBN wheel (from Ken Rizza) on my Tormek for several years now. It leaves a pretty good finish on my spindle gouges and I love not messing with the water and occasionally truing the wheel. It is fantastic to sharpen an existing tool - only takes a few seconds.

However, it wouldn't be much good for reshaping a bevel. For that I use either a 600 grit CBN on a 1/2 speed grinder or for heavy reshaping, an 80 grit CBN wheel. I also have a 220 grit CBN but with the others I don't even use it any more.

Based on my experience and the way I like my edges, I would definitely not be happy with a 220 grit wheel. My choice for two wheels only would be the 600 and one coarser, 180 or coarser. For axes I prefer a 1" belt sander with 80 grit. For knives I really get picky and use a RealSharp belt-based sharpener, two abrasive belts and a honing/polishing belt - I like that far better than even the fine CBN or water wheel on the Tormek.

If mounting two CBN wheels you might be happier with a 1 hp grinder. Some 1/2" bench grinders are a little wimpy on startup. Rizza offers a 1-hp Rikon grinder with two wheels for a reasonable price.

Too bad you don't have more space! Just to rub it in, this is my sharpening station before I added a second Tormek. The other bench grinders and belt sanders are in my little metal working and welding shop. Maybe a bit over-the-top? Nah. :)

407937

Too bad you don't live closer - you could try these for yourself. You might talk to Rizza - he may be willing to exchange wheels if you are not satisfied with what you get.

If you want to try a 600 CBN Tormek wheel I have a spare. I used it for a while before deciding I wanted a finer wheel. I could bring it to you but I won't be up your way until Sept.

JKJ

Sam Murdoch
04-14-2019, 8:31 AM
John - you make me smile - I would need to add a new shop wing dedicated to grinding and edge maintenance to house your set up. :rolleyes: :) Good for you though. Only over the top if they are mostly idle. Not likely - I'm guessing.

In my little space, I would like to add a Viel S-5-M belt sander for reprofiling knives but still trying to get a good set up for my edge woodworking tools, after all these years and shall remain focused. Thanks for the offer to try a 600 CBN. I'll pass as I think Derek, Fred and Phil, have persuaded me that 180 will be fine enough.

Now I will study my options for grinder/wheels combos.

Thanks for sharing.

Sam

Rick Kruger
04-14-2019, 1:27 PM
I have and use a Tormek T8 with a variety grinding wheels, all but one are Tormek. I agree they are slow, but I believe they can give superior results. To improve the speed of creating or reprofiling edges, I use an 80 grit, 1"x 8" Norton 3X grinding wheel (meant for a high speed grinder), fitted with a stainless steel 12mm hub on my Tormek (in the water bath). Works great, speeding things up fairly well. I still want a variable speed Viel belt sander as it would serve that purpose better, but also would have a multitude of other uses in my metal and wood working shops.

I could use another Tormek, so if any of you who are disenchanted with theirs and are willing to sell, I may be interested. If so, please PM me offlist.

Rick

Derek Cohen
04-14-2019, 1:35 PM
Rick, the issue with your set up, compared with a CBN wheel, is that you always have to surface the wheel. Plus, because it wears, your settings change. CBN wheels do not wear appreciably - will last decades - and the settings never need to change.

The Tormek is a fine machine, but outdated in comparison to a dry grinder with CBN wheels.

https://i.postimg.cc/859kvKyy/Sharpening-Station1.jpg


Regards from Perth

Derek

John K Jordan
04-14-2019, 1:44 PM
...Tormek. I agree they are slow, but I believe they can give superior results...
I could use another Tormek, so if any of you who are disenchanted with theirs and are willing to sell, I may be interested. If so, please PM me offlist.


I looked for years for a second Tormek, used, since I didn't want to pay the new price. I finally saw one on Classifieds here.

Even with the 1200 grit CBN I still got a better grind on my tools with the Tormek water wheel so I wanted to set one up with the water again mostly for my smallest spindle gouges. The 1200 CBN sure is quicker and less hassle to use, though. I can get the edge as sharp as with the water wheel but it just takes more honing/polishing. BTW, I use Tormek tool supports on my bench grinders so if I want to reshape a tool I can do it quickly on the grinder then move to the Tormek for the finer sharpening. It turns out the difference between the 8" grinder wheels and 10" Tormek wheel is not significant so going from 8" to 10" doesn't take much time.

JKJ

John K Jordan
04-14-2019, 2:15 PM
Sam, one thing I forgot to mention: a new CBN wheel cuts much more aggressively than one that is "broken in." Reed Grey once said it took about a month of use until the wheel settles down. (This might be a Reed month!) I think it might be because the electroplating method leaves some sharp grit particles standing up higher than the average and until those are broken off with use a given grit might act like a significantly coarser grit. So if your new wheel seems too coarse maybe use it a while before judging. That's what I did before I decided 600 grit on the Tormek was not fine enough for me.

I do use my sharpening things a lot! I prefer the wheels with square corners instead of the radiused and I also insist on wheels with 1" of grit flat on each side - very useful on occasion, lets me easily grind special-purpose tools like this:

407953

I loves my shop! I cleared a spot by the barn a few years back and built a 24x62' building, room for wood, office, welding, machining, maintenance, electronics, animal care, and more.

But my primary interest is woodturning and teaching woodturning. My lathe "alcove":

407954


But now it's getting crowded and I'm planning to add a wing! For example I recently reorganized to put an incubator and hatcher in the shop because the climate control is better for the incubator function. My goal is to hatch peafowl eggs and I'm now raising the first test batch of about 40 chicken eggs in the turning wood storage and maintenance end of the shop.

407951 407952

Besides that, I really want to add a bathroom, shower, and tiny kitchen!

JKJ



John - you make me smile - I would need to add a new shop wing dedicated to grinding and edge maintenance to house your set up. :rolleyes: :) Good for you though. Only over the top if they are mostly idle. Not likely - I'm guessing.

In my little space, I would like to add a Viel S-5-M belt sander for reprofiling knives but still trying to get a good set up for my edge woodworking tools, after all these years and shall remain focused. Thanks for the offer to try a 600 CBN. I'll pass as I think Derek, Fred and Phil, have persuaded me that 180 will be fine enough.

Now I will study my options for grinder/wheels combos.

Thanks for sharing.

Sam

Sam Murdoch
04-14-2019, 4:06 PM
John, sounds like you've got great things going on. Me? I am very much into the lessismore phase of life. Still lots of projects and in the biz too.
Still - Je ne suis jamais seul avec ma solitude.

Thanks for the heads up about the break in period with CBNs.

sam

Derek Cohen
04-14-2019, 7:51 PM
John, do you do any honing after grinding, or is your grinding your final step? I imagine that you can get away with this on lathe chisels after a 1200 grit CBN wheel.

As a predominantly hand tool user, I have always considered the Tormek as a grinder, and not a sharpener (Tormek view it as a sharpener because of the wheel strop). It is not advisable to end on 1200 grit. I finish on waterstones to 13000 or better. Consequently, when using the Tormek, I would keep the wheel at 220 grit and not re-dress it to 1000. What is the point of 1000 - it just grinds too slowly. 220 is slow as well on the Tormek.

180 grit CBN at speed works quickly and leaves a better surface than the 220 grit Tormek. Even the 80 grit CBN off the bench grinder is pretty good. All will be honed on waterstones, so smoother is unnecessary.

Regards from Perth

Derek

Rick Kruger
04-14-2019, 8:32 PM
Derek,

You make the assumption (and I did not specifically state) that the only wheels I have and use are the Tormek matrix grindstones. I have all three grits of the diamond wheels, which do not wear and change diameter, so settings do not change between them. CBN wheels are commonly used on Tormek machines, even in the water bath, with suitable anti-corrosion solution. I don't have any CBN wheels, just the diamond wheels, the two matrix wheels (SG and SB) and the Tormek Japanese waterstone (SJ) wheel, all of these latter wheels do change with truings.

I often prefer the matrix wheels and use them for more routine knife sharpening. For higher end knife steels, the diamond wheels usually produce better results. All of the grindstones can be further refined with the SJ wheel and require little deburring or stropping.

Burr removal is the real key to getting really long lasting sharp edges. Quite a bit of advancement has been made and discussed on the Tormek forum, for any with an open enough mind to take a look.

So, ultimately, with the advent of the Tormek diamond wheels and the ease of use of CBN wheels on Tormek machines, it isn't nearly as outdated as some might think.

Rick

Rick Kruger
04-14-2019, 8:38 PM
I also use the Tormek supports and jigs on my 8" Rikon low speed grinder for some of those fast steel removal and reshaping tasks. Works great. I have, but have not set up yet, the same supports on a buffer that will have paper wheels for deburring and polishing using diamond pastes at the 0.5-0.2 micron level. These techniques have been advanced and shared on the Tormek forum, primarily by an outfit in Australia, Knife Grinders (http://knifegrinders.com.au/).

Rick

John K Jordan
04-14-2019, 9:31 PM
John, sounds like you've got great things going on. Me? I am very much into the lessismore phase of life. Still lots of projects and in the biz too.
Still - Je ne suis jamais seul avec ma solitude.

Thanks for the heads up about the break in period with CBNs.

sam

I think of being alone not as loneliness but as quietness and peacefulness, with the fullness of introspection, contemplation, creative exploration, or simply being, all on the other end of the spectrum from things like the assault by sporting events or TV, of which I refuse to participate.

My wife is interested in the less and suggests that 43 animals is enough. I agree and have already given away a high pedigreed llama before it is born (due in about a week). I do, however, very much enjoy experiencing certain frantic busyness, such as watching the beehives in action. The guineas are entertaining too.

JKJ

John K Jordan
04-14-2019, 11:00 PM
I always hone/strop after grinding. Some detail follows. I can go with the "grinding" vs "sharpening" terminology.

I might call using either the 600 or 1200 grit CBN wheel "finish grinding". I grind with coarser wheels on the bench grinder for rough shaping, sticking to the 80 grit these days. I go directly from the 80 grit to 600 or 1200 - don't think I've used my 220 grit CBN for a couple of years - I don't see the point of using a wheel too fine for shaping quickly and too coarse for honing/polishing quickly.

I think that due to the violent nature of sticking a sharp tool into rapidly spinning wood in woodturning the sharpening can be different from hand tools - it's a waste of time to spend too much time with very fine stones since the microscopically perfect edge you might put on a dovetail chisel would probably be gone almost immediately when turning. Also, most tool edges have compound curves which is not easy to dress by hand with very fine, flat stones.

For my lathe spindle gouges I grind on the 1200 grit CBN wheel on the Tormek. I use the honing compound on the Tormek 8" leather wheel for the spindle and other curved gouges. I use Tormek's leather profiled honing wheel for inside the flute. This gives removes the grinding burr and gives a polished edge in just a few seconds, perfect for detailed work on the lathe. When using the Tormek with water wheel I really liked dressing it with the fine side of the stone then polishing on the leather wheels.

Note that grinding/sharpening spindle gouges with even a very fine Tormek wheel only takes a few seconds since very little metal is removed, an extra 30 seconds if I need to I set up the jig. (To save on setup time I keep six spindle gouges with identical grinds and only have to set up the jig once to do all six.)

For my lathe skew chisels with straight edges I grind on a 600 grit CBN wheel on a bench grinder use a piece of MDF with honing/polishing stick/compound rubbed into a surface resawn expose a bit of roughness. I use this to touch up bench chisels too after sharpening with a series of ceramic stones. Skews with curved edges are done the same way but with a little coordinated arm waving. Note that my chisel sharpening and use is pretty crude compared to the neander norm. When a lathe skew chisel goes dull I first strop on the MDF surface a time or two then when that loses effectiveness I touch up the edge with the Eze-Lap diamond hones and MDF strop a few times before going back to the grinder.

For the lathe negative rake scrapers and traditional lathe scrapers I grind with the 600 grit Tormek wheel then hone off the grinding burr with an extra fine Eze-Lap diamond hone (the blue handled one) before turning a cutting burr with a burnisher.

For curved hand scrapers I grind the edge with the 600 grit Tormek wheel then continue as with the NRS.

For plane irons I do the best I can with the Tormek and stones. Again, my standards are low compared to the community of plane lovers. But I rarely use planes except on doors and decks.

Chip carving knives in good shape are sharpened differently (http://mychipcarving.com/product_info.php/sharpening-kit-p-77) when needed then stropped on pigs leather glued to wood. This method works amazingly well when following the My Chip Carving instructions. Carving gouges are usually stropped.

That's about the extent of my sharpening except for knives.

BTW, my honing/polishing of lathe tools might be a little different compared to what I read most people do. Most seem to use the tool directly from the grinder, not even removing the grinder burr. For one thing, those who turn bowls from green wood are happy with less since the wood cuts so easily compared to hard, dry woods. (Love ebony, lignum vitae, gidgee, dogwood, "iron wood", rock maple, etc) Another thing: a grinder burr is quickly knocked off on the lathe. (I disagree with working this way on principle. A clean cut with a polished edge on good wood needs very little sanding.) I like to turn a lot of smaller things with detail, using tools and techniques different than what's used for big bowls.

408001 408003 408005

BTW2, I don't really see the point of using CBN on the Tormek if diamond is available. But at high speeds CBN shines compared to diamond.

JKJ


John, do you do any honing after grinding, or is your grinding your final step? I imagine that you can get away with this on lathe chisels after a 1200 grit CBN wheel.

As a predominantly hand tool user, I have always considered the Tormek as a grinder, and not a sharpener (Tormek view it as a sharpener because of the wheel strop). It is not advisable to end on 1200 grit. I finish on waterstones to 13000 or better. Consequently, when using the Tormek, I would keep the wheel at 220 grit and not re-dress it to 1000. What is the point of 1000 - it just grinds too slowly. 220 is slow as well on the Tormek.

180 grit CBN at speed works quickly and leaves a better surface than the 220 grit Tormek. Even the 80 grit CBN off the bench grinder is pretty good. All will be honed on waterstones, so smoother is unnecessary.

Regards from Perth

Derek

Sam Murdoch
04-15-2019, 9:07 AM
In the "For what it's worth" department - this is the advice I received from WoddTurners Wonders on the subject -

"Our advise is that if you have a means of rough shaping a tool, then buy a fine grit CBN like a 350 or 600. The finish on both will be far superior than you can ever get with a stone wheel. Later, you can augment with the 180 or even an 80 if you need to do a lot of material removal."

Realizing that "grinding" is not my main objective here (though I did suggest the possibility in my 1st post) - I don't do rough shaping on tools but rather reconditioning edges that need more work than some bench stones can achieve. I do have chisels that get used in the field and get dinged by the odd hidden saboteur. These definitely could use some light grinding - otherwise I am looking to set up for edge maintenance on my edge tools. From the CBN to my bench stones and strop for sharp.

If I were to buy just one wheel for now (and an 8" - 1/2 speed) - is the consensus that the 180 CBN is fine enough? 350 now with a 180 later, even better? I don't want to bother Ken with swapping out wheels that I regret buying. The price doesn't change with the higher grit so in this regards $$s is not a consideration - simply achieving the best results.

Thanks again.

Sam

Derek Cohen
04-15-2019, 10:05 AM
Sam, John is discussing the CBN wheels he uses a turner, not as a flat woodworker. While his information is interesting and valuable, it serves to confuse the issues for a newby to CBN, such as yourself. If you are aiming for a single wheel, get the 180 grit. I use it 90% of the time, with a 80 grit the other 10%. At some stage I will get another grinder and add a 350 grit, but this will be for lathe chisels only. Most turners work from the grinder. Bench chisels and planes blades are finished on stones.

Regards from Perth

Derek

Sam Murdoch
04-15-2019, 10:12 AM
Sam, John is discussing the CBN wheels he uses a turner, not as a flat woodworker. While his information is interesting and valuable, it serves to confuse the issues for a newby to CBN, such as yourself. If you are aiming for a single wheel, get the 180 grit. I use it 90% of the time, with a 80 grit the other 10%. At some stage I will get another grinder and add a 350 grit, but this will be for lathe chisels only. Most turners work from the grinder. Bench chisels and planes blades are finished on stones.

Regards from Perth

Derek

Thanks Derek - I admit to getting a bit of a burr on the matter. :)

Sam