Hi guys,
The Japanese Sun Tiger 800 grit grinding wheel has become available as of today from this German seller:
http://www.fine-tools.com/Tormek.html (http://www.fine-tools.com/Tormek.html)
Note that Japanese grit JIS #800 corresponds to US ANSI #600, and European FEPA #1200, i.e. is somewhat finer than 'finely' graded Tormek #1000.
The main advantage of using a dedicated 800 grit stone over graded Tormek standard SG is that you do not have to grade finer grit from the original 220 grit, and hard grading can untrue the wheel and get the corners out of square (the latter mostly frustrates knife sharpeners).
In 2009 Ionut had said all I could possibly say on this topic, so I just refer to his original post, a fragment of which I quote below:
http://forum.tormek.com/index.php?topic=897.0;nowap (http://forum.tormek.com/index.php?topic=897.0;nowap)
"... the so called 1000 grit in my opinion is far from it. If you compare the scratch patterns between the Tormek wheel graded at 1000 and an actual 1000 stone there is a huge difference, and if you add a magnifier glass everything gets amplified. I've tried hardly to grade the stone to get closer results to the real 1000 I pressed the grader so hard I stalled the motor and the best thing I've done when pressing so hard and for long time was to untrue my wheel.
Using a 4000 Japanese stone the Tormek version SG250 for a secondary micro bevel improved a lot the amount of time the edge remained sharp, but I still was not where I wanted.
I got an aftermarket 800 Japanese stone and now I am tempted to change my occupation from "wooder" to "sharpener". All my bevels now are looking as they were before and the big difference is the edge stays as when I was using the manual version to sharpen my tools.
... with this settings all my search for getting always a perfect sharp edge VERY FAST, is over.
Ionut"
Thanks Wootz for the info about availability of alternative grindstones for Tormek and also for your selection of great Ionut's quote. You have opened very interesting topic. :)
I fully agree that the graded SG Tormek grindstone is not equivalent to real 1000 grindstone. Especially when sharpening fast, using the graded grindstone, we create deep scratches. It is known, that the surface structure of the metal is disturbed to a depth, which is much greater than the depth of the visible scratches.
My understanding, why the edge stays longer sharp when sharpened on finer grindstone is following: deep scratches in the metal surface, caused by low grit stone, can serve as stress risers, which can initiate fatigue cracks or some other defects near the edge surface.
(https://photos-2.dropbox.com/t/2/AABQwxzaaayOx58OpyLP9DVA9tAYn9sHx7dxuChBPbjvBA/12/484370172/jpeg/32x32/1/_/1/2/CRACK.jpg/EOiO4vYDGFggBygH/3HYA8ANl_x709WnSjxfjt6qjwA-IT3PKC25MkBV-3fM?size_mode=5)
The movement of material along slip planes caused the extrusion of the metal surface.
Jan
I remember when Ionut originally posted the topic. As I think highly of Ionut, I purchased one of these wheels. It is indeed less coarse than the ungraded SG wheel. This is both an advantage and a disadvantage. I found it slower than using the SG wheel. Yes, no time is lost by regrading the stone. However, the wheel has no coarse properties.
As I recall, the wheel was slightly oversize. It was a minor nuisance. The wheel also fit the bore very tightly. Changing wheels would not be convenient.
I was one of a number of forum members not keen on grading the grinding wheel. I decided I was not really a position to have an opinion on this until I became more fluent with the stone grader. I have reached the conclusion that if someone really wanted to avoid using the stone grader, the solution is two wheels, each mounted in its own Tormek.
Does the time saved make having two Tormeks cost efficient?
Ken
Jan's post came in as I was preparing mine. What steps can we take to approach the ideal?
One recent modification in my technique is based on a suggestion Stig made. With all stages, I use lighter pressure for the last few seconds. This makes the scratches shallower.
For those of you who like to tinker, I have had good results using valve grinding compound with the leather honing wheel. My initial observations lead me to think that this could substitute for using the stone grader in many situations. VGC cuts more agressively than Tormek honing compound. Please note that it does not leave as polished finish as the Tormek compound. If you want to use both, a spare leather honing wheel is much less expensive than anyone's grinding wheel, and isvery fast to change.
I do not see the 800 grit wheel as a replacement for the SG wheel. I do see possibilities as an auxilliary wheel for advanced users. Consider it when you are working on you second SG.
Ken
Ken, do you have some experience with sharpening HSS using the 800 grit grindstone?
Jan
Jan, sorry. I used the 800 grit on a couple chisels. I was not really impressed, so it has been in the box ever since. I don't work much with high speed steel.
Ken
At 40X magnification, as I've mentioned before, the finely-graded Tormek SG grindstone leaves visible scratches in an edge. Honing on the leather wheel polishes the regions between the scratches.
While Jan likely has a point about these scratches causing fatigue and shortening the life of an edge, they also add a "tooth" to the edge that is an advantage for many cutting and chopping tasks in the kitchen and elsewhere.
I have a mild curiosity about how an edge ground with a dedicated Japanese Water Grindstone would look at 40X. But the price is too high for me to justify satisfying that curiosity.
Herman, I have long had a 4000 grit Japanese water stone and used it sometimes. I say sometimes because I regard it as more of a polishing stone than an actual sharpening stone. The instructions or maybe not them but something I read on the internet suggest that you do not need the leather honing wheel when using this stone. Indeed, it is almost like glass. I am going to order a 40x loupe right now, it is less than $5 on eBarf. Though not scientific quality, it might answer your questions.......................and mine. When it arrives, I will do some photographing and we will see what happens. I have a Canon 100mm macro lens that hopefully will do the job. Be patient as this might take a while.
Quote from: jeffs55 on January 21, 2016, 06:16:45 AM
The instructions or maybe not them but something I read on the internet suggest that you do not need the leather honing wheel when using this stone.
I believe that's the Tormek recommendation.
That is correct.
Ken
True if using Tormek honing compound.
Japanese Industrial Standards (JIS) 4000 grit is 3 micron particles, and Tormek Honing Compound consists of 1-3 micron particles, effective 3 micron.
However, extra sharpness can be achieved by honing with Chrome Oxide, which is 0.5 micron.
So, after SJ, I hone the blade on the Tormek honing wheel loaded with Green Rouge, and this invariably gives a sharper edge.
For harder steels, I also have to add a few puffs of 100,000# (0.25 micron) diamond spray over the honing wheel already covered with Chrome Oxide.
For example, I could never achieve hair splitting sharpness with SJ 4000 alone, shaving - easy, but as to the hanging hair test, the best I got was 'violin', but even that not always.
After honing with Chrome Oxide, hair splitting is a usual result.
In the "Experiments on Knife Sharpening" by John D. Verhoeven, in the chapter "Experiments with the Tormek machine", honing on the chrome oxide loaded leather wheel produces 0.35 microns edge as shown by scanning electron microscope.
The human hair cuticle is about the same thick, and a blade that sharp whittles a human hair lengthwise.
(Hanging hair test is detailed here http://straightrazorplace.com/srpwiki/index.php/Hanging_Hair_Test,_from_trick_to_probing_method#Controversy.3F (http://straightrazorplace.com/srpwiki/index.php/Hanging_Hair_Test,_from_trick_to_probing_method#Controversy.3F))
Whilst hair splitting sharpness is very super cool, don't get me wrong, unless you are trying to make razors, cell pokers for gene experimentation or just the shear joy and understanding of achieving it, that type of ultra sharpness dulls quickly when suffering everyday use such as with kitchen knives.
With that ultra sharpness the edge is so thin it is comparatively weak compared to a knife that is just good and sharp. The joy of watching the knife slice through a butternut squash under nothing more than its own weight is indeed rewarding but repeatability before it dulls to just really sharp is so ephemeral it's rarely worth the extra effort
"...cell pokers for gene experimentation " ;D bugagaga
Can't argue that, it's definitely not for professional high volume work.
I do the full sequence for collector's knives though.
And sadly true that "repeatability before it dulls to just really sharp is so ephemeral" even with the high-end steels.
Wootz sayeth: "I do the full sequence for collector's pieces though".
I'll bet that if you exacting such care with your work, the result is truly beautiful and impressive!
Quote from: grepper on January 25, 2016, 03:43:48 AM
Wootz sayeth: "I do the full sequence for collector's pieces though".
I'll bet that if you exacting such care with your work, the result is truly beautiful and impressive!
...yeah, and equally impractical.
One of many unnecessaries people do for "shear joy and understanding of achieving it"
Enjoyed your comment, thank you for good laugh
"One of many unnecessaries people do for ""shear joy and understanding of achieving it""
Great craftsmanship generally results in not only personal satisfaction for the craftsman, but also, for those capable of joy and understanding, great beauty. A life void of joy, understanding and beauty is a barren life indeed.
The joy of watching the knife slice through a butternut squash under nothing more than its own weight is indeed rewarding but repeatability before it dulls to just really sharp is so ephemeral it's rarely worth the extra effort
NO knife unless it is of such a weight as to render it unusable by mere mortals will ever slice through a butternut squash of its own weight! Not even after baking it into a pile of slag will your knife slice through this skin under its own weight unless it meets the above criteria.
I understood butternut squash as a due sarcasm on obsession with super sharpness, bringing to mind other sharpness legends, like
- katanas put upright in a stream should be able to cut cleanly through any leaf that floated down to touch the edge;
- the knightly sword should be able to sever a human hair floating in the air;
etc
Well..., huh. I guess my exaggeration therapy was a failure, even though I gave it 110%. :)
Quote from: grepper on January 25, 2016, 07:10:03 AM
Well..., huh. I guess my exaggeration therapy was a failure, even though I gave it 110%. :)
Mate, don't get me wrong, but there is no such thing as 110%
:)
Good humor!
I have a hobby interest in measurement, especially in machine shops. Inspection tools are more accurate than the tools used on the shop floor. The calibration tools used to check the inspection tools are even more accurate, and they are sometimes checked by the National Bureau of Standards. We should all be capable of creating keener edges than are usually required.
Ken
I got both SUN TIGER wheels for my Tormek-7: 800 grit out of necessity, and 4000 grit out of curiosity.
Now that I've had sharpened half a dozen knives on them, can share observations.
The SUN TIGER wheel diameter is 254mm.
The water trough fits almost flash, yet no brushing, no issues here.
I read Ken's concern that the wheel fits the bore very tightly, so as precaution before fitting the wheel I smeared the bore with a lanolin grease, but this was not needed with the wheels I got; I have no difficulty changing them.
The wheels had to be trued a little out of the box, but this is the case with standard wheels as well.
They soak up water slower, about 30 min.
I use KING Nagura stone for smoothing out after truing and for declogging the #4000 stone, and fine side of the Tormek grading stone for #800.
SUN TIGER 800 grit compared to finely graded SG
Note that Japanese grit JIS #800 corresponds to US ANSI #600, and European FEPA #1200, i.e. is somewhat finer than 'finely' graded Tormek #1000.
Sharpening on SUN TIGER wheel is a symphony.
No shortcomings of graded SG mentioned in the beginning of this post: hard grading can untrue the wheel and get the corners out of square, also, with use, the graded SG gets rough spots where the original grain somewhat opens.
2 thumbs up for SUN TIGER
SUN TIGER 4000 grit compared to SJ
Not that unequivocal.
SUN TIGER is definitely denser, it won't flake on the corners when trued or declogged (while truing SJ often leaves ragged edge), doesn't clog as fast, and won't wear off as quickly.
However, SJ is finer.
SJ leaves perfect mirror surface, and doesn't require deburring/honing afterwards. After SJ I can't feel a burr with the thick of the thumb.
SUN TIGER 4000 leaves a palpable burr that must be honed away, and the resultant bevel is not as shiny.
I'd say SUN TIGER grit is 1000 JIS less than SJ.
As a sidenote, they say SJ grit is 4000, but from my experience with bench stones I'd grade it at 5000.
Good preliminary testing, Wootz.
I really did not use my Tiger wheel enough to fairly comment. At the time, I was sharpening primarily chisels. Being 800 grit, it did not seem to cut as quickly as the SG graded coarse. That's understandable.
In considering the SG-250, it is only fair to remember that until November of 2008, the SG was the only grindstone for the Tormek. It was expected to work with all of the Tormek jigs and different kind of steel.It was expected to sharpen planer blades, including removing nicks. It was expected to reshape and sharpen turning tools, both carbon and high speed steel. It was expected so sharpen tools sized from small carving tools to axes. In conjunction with the leather honing wheel, it was expected to handle the whols sharpening process from grinding through honing and polishing. No dry grinding wheel, bench stone or sanding belt is expected to do so much.
In truth, the SG was not always a speedster at all of these things. Howbever, it did do them. It has also been expected to be long lasting. That's a tall order for any grinding wheel.
I am not surprised that the 800 grit wheel seems a useful adjunct for the Tormek. I have found the two Norton 3X wheels (46 and 80 grit) useful additions. Neither of the 3x wheels will ever be my general purpose wheel. They do help when I have a lot of grinding to do.
The SG grinding wheels are the old reliables which do most of my sharpening.
Ken
Always tempted by more sharpening stonez, I too could have been seduced to buy a dedicated 800 grit or 1000 gritsone, however I have discovered the effortless secret to grading the stone effectivley! The secret is to use cheap diamond sharpening/lapping stones to grade the Tormek wheel and I mean cheap the one I use cost me a few pounds plus I have a couple of lapping plates bought of ebay which again were much less than a tenner.
The diamond sharpening stone that I have has a 200 grit on ones side, Other grits I use are 1200 grit and 3000 grit. I find these give much better, faster and consistent results to the stone grader, very little pressure is used. It really takes very little effort and when changing to the 1200 grit (cause that's what I had) it gives a smooth surface. When I use the grader I always feel a few particles that have not been crushed that leave anoying scratches. Now I dont worry about changing grit when I need to, cause it's no trouble. Really I dont know why tormek stick with the stone grader I almost sold my Tormek because the results were so poor but it's was the stone grader. I'm sure some Tormek experts can use it but I get better results with cheap diamond stones. Most people who need to do some sharpening and have a tormek probably have some diamond stones lying around to give it a try.
Hope that helps someone.
Thank you Titian for sharing your experience and views. :)
For me the whole grading/dressing procedure remains somewhat mysterious.
Your successful usage of the diamond sharpening stone may indicate that you are reliably reaching the necessary depth of dressing cut, while some users of the Tormek stone grader may cut too shallow.
I searched for recommendations concerning the depth of dressing cut and got a few and even more ambiguous results. :(
The best reasoned guidance was to make the depth of dressing cut equal to 10 to 30% of the average grain diameter. For 220 grit stone the average grain diameter is some 0.07 mm and so the recommended depth of dressing cut would be 0.007 to 0.02 mm. To measure such a small changes is beyond our possibilities.
Interesting for me was finding a note that too large depth of dressing cut can result in lower grindstone performance caused by insufficient grains protrusion.
Jan
Fascinating comment, Jan. I had not thought about the depth of the dressing cut. I will now.
Ken
Thank you Ken, it's simply my way of thinking about "Why is it so? ". I am happy if I have inspired you. :)
Jan
As I understand this is that Titan is "polishing" the stone with a 1200 grid diamond stone which will flatten the stone and make a temporary 1000 grid stone.
It may take less time than using the SP-650 but new grids will appear as usual so it's a constant work if you need a very fine stone, as with the SP-650.
We believe the SP-650 works very well and it is design to work with all our stones.
What I have noticed is that many users are a bit to gentle using the stonegrader and therefore it takes longer time. I normally use the stonegrader 15-20 seconds to achieve the grid I want. And I always listen to the stone and visually check the result on my tool before going "All-in".
Best,
Stig
Further to my previous notes on the aftermarket stones for Tormek, a summary of experience sharpening knives on them for the last year.
In one sentence, SUN TIGER's grinding wheels for Tormek are good for conventional carbon and stainless steels, but will not grind high end tool steels, whereas Tormek's have no problem with the latter.
Tormek's Japanese SJ proved better than SUN TIGER's #4000 almost in every aspect; nothing to discuss.
#800 SUN TIGER's grinding ability is limited to mainstream carbon and stainless steels. It cannot grind wear resistant high end tool steels, in particular those with Vanadium content over 4%.
E.g. from my experience it struggled but still ground Latrobe CPM-20CV, and Bohler-Uddeholm M390 and Vanadis-4, but was useless on Vanadis-10, Vancron 40, S290, and CPM S110V.
Tormek's finely graded SG has no problem grinding any of them.
Physical make of SUN TIGER's grinding wheels concedes to Tormek's.
SUN TIGER's wheels have pronounced lateral wobbling.
SUN TIGER's are softer and easily chip off, therefore truing any of them you have to take the same precautions you usually take only with Tormek's Japanese SJ.
All that said, last month I ordered another #800 SUN TIGER's grinding wheel as you can't beat the advantage of a dedicated fine stone.
Perhaps it's time for Tormek to seriously consider the profitability of producing a few additional grindstones of various grit.
Hmmmm ...... grit .... that made me hungry for some grits. More later ..... R ;)
Support the idea!
I would ask for a stone good enough for HSS and a grit of 80.
How about a CBN stone?
Rolf
Rolf,
You can get most of what you want. CBN wheels are available for around $300 US. One brand matches Tormek's 250 mm x 50mm size with grits as coarse as 200. Another brand sells 80 or 180 grit wheels slightly narrower (40mm). According to Dave at D Way, his CBN wheels can be used wet or dry. My choice would be to use the wheel wet, and take advantage of the cool, dust and spark free environment.
My first choice would be a Tormek CBN wheel, which is not presently available. I have no inside information, however, I would be surprised if Tormek is not developing one.
I have posted about my choice, Norton 3X 46 and 80 grit wheels 200mm x 25mm. The size is not ideal, however, I know from personal experience that these wheels work very well. The 46 grit made quick work (about five minutes) of reshaping a gouge from jig setting 2 to 4. The gouge remained quite cool during the wet grinding process. The 3X wheels cost around $50 US each, and need a simple homemade adaptor to match Tormek's 12 mm shaft.
Again, not the same as a Tormek wheel, however, for fifty bucks either of these work amazingly well.
Ken
Ken,
thank you very much for all the information.
May I ask which brand has 250 x 50 mm? At D Way I only find one with 38 mm and the wheel will not fit the Tormek shaft.
Rolf
Rolf,
Here is a link.
D-Way can provide a 12mm bushing.
Duty calls. More later.
Ken
http://woodturnerswonders.com/products/tormek-cbn-wheel-600-grit-10-x-2-inch-12mm-arbor
The availability of Tormek-like machines, jigs, and grindstones is a testament to the success of the Tormek brand.
It's a credit to Tormek that they even allow discussion of these products here on their very own message board. Apparently they have confidence in the quality of their own products, which is based on the fact that their products do indeed perform very well. Moreover, when problems do arise Tormek is diligent about making amends and corrections.
Quote from: Ken S on October 28, 2016, 01:34:56 PM
Rolf,
Here is a link.
D-Way can provide a 12mm bushing.
Duty calls. More later.
Ken
http://woodturnerswonders.com/products/tormek-cbn-wheel-600-grit-10-x-2-inch-12mm-arbor
Thank you so much for this info, Ken.
Now I seriously consider getting some from them, and hope, as one of the customer reviews there says, that these CBN wheels will make me love my Tormek even more.
Can you guys think of any potential pitfalls with CBN wheels use on Tormek?
Wootz,
I can't locate it now, however, I remember reading one CBN dealer's claim that he had sold "thousands" of his CBN wheels to Tormek users. As I can't locate the quote now, consider it hearsay evidence, not associated with any particular company.
What puzzles me is that I have not encountered any of these thousands of wheels even though I do occasionally follow the Tormek forum
Drawbacks? Let's call them concerns or considerations:
My first concern would be getting a well made 12mm bushing adaptor, preferably in stainless steel. I would prefer to purchase the adaptor from the same source as the wheel, but, for me, stainless would be the first consideration.
Ideally, I would like a CBN wheel to be the same dimentions, both diameter and thickness, as the Tormek I was using. This may involve compromising on one or both dimensions.
Unfortunately, we don't have much data involving choice of grit. I would hope to only need one CBN wheel. Again, this may involve some thoughtful compromise. My personal choice of grit would be influenced by my oreference to use it wet. I have a belt grinder, another useful tool. I like it, but I spent as much time keeping the ground object cool as in actual grinding. I also dislike all the loose grinding dust.
I would question the CBNdealers about the possibility of rust when using the wheels wet. Dave at D Way has told me his wheels work wet or dry. I did not specifically ask him about any rust issues. (Dave uses his wheels dry on a high speed grinder.)
One of the comments on the Tornado site mentioned a preference to use the wheel wet. No mention of using a magnet with the water trough. As the debris is all metal, I would consider a magnet, either built in or taped/glued on, a real improvement. The T8's removable magnet is ideal. the metal particles are held in place and then can be released.
I would inquire about using honerite with the water. Considering not having to true a constant diameter wheel, I would consider the cost of the honerite a bargain.
I purchased the two 3x wheels I tested. I did this as a forum project, as I have no need for reshaping. I have considered purchasing at least one CBN wheel for forum testing. The constraint for me is the three hundred US dollar price tag. I would think differently if I was an active turneror a professional sharpener.
Do keep us posted if you decide to try a CBN wheel.
Ken
Is there any reason to think that (unlikely but potential) warranty issues with the basic Tormek unit, 2 / 3 / 5 years down the road, might call into question the use of non-Tormek accessories (grinding wheels) ?? R ???
At least some of the wheels sold were steel. I would check the shaft and bushings more often with them, as I haven't found a weight compared to the Tormek stones. It seems that some changed to aluminum (and others may have always been that way). There are multiple sellers, and some do have the correct diameter wheel, as well as the correct shaft diameter. (I think they may be more across the pond sellers, several of the US ones I saw, show 1/2" arbor)
Now there have been many low post members that popped in and out over the years, and probably more that never registered and just searched and left. How many Tormeks have been sold? Thousands of those wheels sold for them, makes me wonder if Ken branched out to any other forums? A quick Google search, leads me to several posts in a woodworking forum I used to visit. There are discussions about grit, wet or dry (and towel drying), rust, etc. From my limited reading, it seems the while both kinds of woodworkers use them, turners use them more and yet lots more use them on a bench grinder, with the BGM kit.
I doubt a consumable would affect the warranty.
All valid points, and keep me thinking.
What also concerns me is the claimed advantage of a CBN wheel that you won't ever have to true it may turn into headache of bringing the Universal Support in parallel with the wheel surface.
I mean there are quite a few variables you have to bring together to have it true: the shaft and its bushings, the washer, the wheel radius consistency, and square position of the Universal Support in the sleeves. With regular stones we match them all together by truing, but it may be hard to fix the mismatch with CBN wheels.
On the positive note, the make at the Ken's link doesn't seem to need a bushing adaptor for Tormek, and is electroplated i.e. should last forever.
Curiosity killed the cat...
There is much that i do not know about CBN wheels. Using any wheel weighing more than the Tormek wheels would concern me. I don't know enough to know if extra weight would cause a problem, or if, indeed CBN wheels actually weigh more than Tormek wheels.
I have no idea if there might be a warranty issue.
I regularly do google searches, and have found posts from other forums. For the record, I do not belong or post to any other forums. The only exception to this is my very inactive membership in the Yahoo Tormek forum, if that forum is still a going concern.
Without knocking any particular forum, it seemed that many of the posts were made by members who were not Tormek users.
I'll take my chances with our group. We don't know everything, but we are all Tormek users, helpful, and curious.
Ken
This is very interesting topic. Sorry I haven't been active lately but I follow in stealth mode :)
Lately I had a client that claimed he had a problem sharpening a knife with his brand new T-8 and SG250 wheel.
He trued the wheel and nothing happened. I was surprised and puzzled as it is not normal, and asked him to pay me a visit with this knife and some more tools he had to get instruction with.
Looking at the knife and putting it on my SG stone confirmed. Then I told him I suspect this is a ceramic knife. He said he didn't think so but he got it from a fiend and was not 100% sure.
I was happy as this is my first time to deal with ceramic knife. I changed the SG to the SB and started the session.
Very quickly it started to sharpen and looking with the loop it confirmed that this is ceramic.
Guess what? He left home with a brand new SB-250 stone happy to be able to continue to sharpen the rest of his 900 piece collection that include hard steel knives too.
I also had 10 chefs knifes that was so dull I could not cut a lettuce with them. Micro bevel was rounded. Perfect job for the SB-250.
I'm not sure I would like to go for a cheap Tormek stone substitut. In order to do that a real test one to one should be performed by the seller in order to convince me els.
Interesting post, WolfY. You are part of a slowly growing number of members reporting good results with the SB grinding wheel.
Do you use a different technique when sharpening with the SB? Specifically, do you place less pressure on the knife against the SB than when you use the SG? I ask this because I believe we have members who are getting poor results with the SB. I do not believe the problem is with the SB itself, as demonstrated by your successful use. I do believe there is an instruction gap with the SB. Your customer is fortunate. He had the opportunity to observe you skillfully using both the SG and the SB and learn the purpose of the SB. He should have good success sharpening his knife collection because of your instruction.
I agree with you about cheap wheels, which are often not so inexpensive. The only reason I started working with the coarse Norton 3X wheels was because Tormek does not sell coarse wheels. My first has always been to use Tormek products. In this case, I had no Tormek choice. I could have used a BGM-100 and my dry grinder, but that choice includes a lot of heat and dust.
CBN wheels are expensive, and a pair of quality whees sized for the Tormek will probably cost more than a new T8. When used with dry grinders, they are typically used in pairs. 80 and 180 grit is a common combination for turning tools. 600 grit, with a back up of 325 is what Tormek uses with its diamond wheels for the T4. I suspect we will soon be wanting 1000 grit and finer. At that point, some of us will lust after multiple Tormeks so we don't have to change wheels.
We have come a long way from Torgny's simple drill powered one wheel wet grinder. Or have we? I think today's adaptable, more sophisticated machine is a tribute to Torgny.
Quote from: WolfY on October 30, 2016, 10:12:26 AM
Lately I had a client that claimed he had a problem sharpening a knife with his brand new T-8 and SG250 wheel.
A most timely post, Wolfy. I had been trying to sharpen a basic, large kitchen knife all weekend and it just wouldn't do it. It should have been the simplest knife in the box to sharpen, based on my woefully inadequate experience. Just wouldn't do it. The only thing my limited thinking could come up with was that it was just very hard steel. So I just proceeded to grind the snot out of it on the SG, and VOILA .... I finally came out with a decent edge on it.
Is there a simple "litmus" test to determine what kind (hardness) of steel you are dealing with? I am a neophyte in these matters. Would appreciate comments on this. I'm happy to pick up an SB if it is warranted. Lee Valley has FREE SHIPPING on right now. BOO-YAH !!!! Thanks. R
A useful product from a solid manufacturer, purchased through a highly reputable Canadian dealer, with free shipping. Four paws up from Rex!
Add some experience, and you're good to go.
Ken
But do I need it ????? Could this be money better spent on my motorcycle ???
Send money !!! R
You probably don't need it, but at least you can not need it fifty two weeks a year instead of needing something for your motor cycle during the week and a half of Yukon summer. :)
Ken
I don't know the prices compared to Tormek and I have the privilege ;D and obligation ;) to use Tormek original products 8). I'm just picking from the shelf ;D
You are right about the importance of sharpening in clean environment. No client or fun sharpening is worth destruction of our health or safety. So water or other arrangements are crucial.
I used the SB same way I did with the SG. As for pressure I think it depends on so many factors that I can't recommend except for starting with only your hand weight pressure and feel the steel reaction.
I believe after some more usage of the SB I will have more conclusions. Will post them of course. But as for now, I will leave it on the machine and use as much as possible. Loved it.
Rem, when saying " I had been trying to sharpen a basic, large kitchen knife all weekend and it just wouldn't do it.", what do you mean? How do you test and why aren't you satisfied with the results or lack of results?
SG stone will sharpen all kitchen knives with ease. Even VG10 and van/moly. I even sharpened D2 and CPM390 on it.
Maybe your sharpening or honing was not complete? Sometime the knife feels sharp and ppl stop sharpening although another pass will make the burr come up and knife will be ready for honing. Some time there is a tiny micro burr left and it makes the knife "dull". Check those situations.
P.S I would buy the SB and sharpen all the bikers D2 and a like knives in order to finance the SB ;)
WolfY
Go WolfY!
Very good advice.
Ken
Quote from: WolfY on October 30, 2016, 04:49:34 PM
Rem, when saying " I had been trying to sharpen a basic, large kitchen knife all weekend and it just wouldn't do it.", what do you mean? How do you test and why aren't you satisfied with the results or lack of results?
Maybe your sharpening or honing was not complete?
WolfY
I had several knives of similar shape and size. Your basic fairly large kitchen knife. The others came out just fine after I did my normal routine on them. This one, after applying about the same amount of time and technique, was still dull. Just by rubbing my thumb over the edge, I could tell. I did this twice. Then I did it a third time for about 3x the time, and it came out OK.
Two questions at this point: 1. Will having to do this wear down the SG abnormally? 2. Is there some way to tell if you're dealing with very hard steel, other than how it reacts to the stone?
REMember, I'm ignert, so be gentle. RR
RR
1. Will having to do this wear down the SG abnormally?
Basically, No. It will not wear the stone abnormally. That is what it is designed to do.
2. Is there some way to tell if you're dealing with very hard steel, other than how it reacts to the stone?
Basically, No. You could always get a hardness tester, but they are very expensive.
However, if you know the make/model of the knife a little research may provide the steel type and hardness. Most kitchen knives seem to be between Rockwell Hardness C (HRC) 55-60. Knives HRC 60+ such as Shun with SG2 and VG-10 steel are very hard and more difficult to sharpen.
http://forum.tormek.com/index.php?topic=1768.msg8926#msg8926
You're the man, g-man. Thanks for the response. Most helpful.
Maybe I can devise a "RemTest" and calibrate the amount of pain caused when I whack myself in the head with various knife blades.
I'll figure it out. Thanks again. Back to the grind. R ::)
r-man,
Check out post #7 here:
http://www.practicalmachinist.com/vb/general-archive/simple-accurate-hardness-tester-80194/
With enough samples and calibration work you might be able to get a reasonably, or at least usefully accurate official Rem scale of hardness. I'm guessing you don't have a lot of yard work to do these days to consume your time.
For under $100 you can get hardness testing files. The downside with those things is that you must scratch the surface of your knife and use some sort of scale or weight to assure equal pressure when testing. I've never tried those and I have my doubts if it would be worth the trouble. I could of course be mistaken, (That would be a first!) ;)
Quote from: Rem on October 30, 2016, 05:26:02 PM
Two questions at this point: 1. Will having to do this wear down the SG abnormally? 2. Is there some way to tell if you're dealing with very hard steel, other than how it reacts to the stone?
Rem, yes, there is a simple method for quick approximate estimation how hard a steel is. It is a set of test files for hardness detection. Usually it contains 6 files at 40, 45, 50, 55, 60, 65 HRC. It is of course not very precise, but you know immediately when you are going to sharpen very hard steel. :)
The damage of the blade surface by the test scratch is quite negligible. Just 2 mm long thin scratch.
I have this set but do not use it frequently. Once I was not able to flatten a back of a planer blade, so I tested the steel hardness and found it was more than 60 HRC. It calmed me down and I continued resignedly for another ten minutes of grinding the blade's back on the side of the grindstone.
Jan
Jan and g-man ..... great information. Thanks so much. I'm gonna look for one of them there file sets. I've never heard of such, but then I hadn't heard of poutine until just a little while ago. I've had a sheltered life.
Seems a reasonable and (hopefully) inexpensive solution. Thanks again. R (-man)
;D
Quote from: Ken S on October 30, 2016, 01:36:33 PM
...
CBN wheels are expensive, and a pair of quality whees sized for the Tormek will probably cost more than a new T8. When used with dry grinders, they are typically used in pairs. 80 and 180 grit is a common combination for turning tools. 600 grit, with a back up of 325 is what Tormek uses with its diamond wheels for the T4. I suspect we will soon be wanting 1000 grit and finer. At that point, some of us will lust after multiple Tormeks so we don't have to change wheels.
Suppose we forgot monetary considerations for a moment and are talking of pure perfection.
The most accurate result will be obtained using the same Tormek machine and changing CBN wheels of successive grits.
While the quickest result within good tolerances is obtained using severals Tormeks dedicated to each CBN wheel.
Ideally, one should have a full set of grits from the same CBN wheel maker, so that he won't have to adjust Universal Support as wheels are changed; from the available from the WoodTurners Wonders I would pick #200, #600 and #1200.
I took advantage of the Make Offer button at the WoodTurnersWonders eBay store, and ordered #600 CBN wheel for $225. Allegedly it is purposely made for Tormek T7/8.
Should be close to a finely graded Tormek SG-250 (ANSI #600 corresponds to European 1000 and JIS 800).
If these CBN wheels stand by their claims, switching to them would eliminate the main consumable and in the long run pay back through saving on stones and graders.
Will share impressions in a month or two.
If these CBN wheels stand by their claims, switching to them would eliminate the main consumable and in the long run pay back through saving on stones and graders.
[/quote]
Are the CBN wheels purported to last longer than the equivalent Tormek wheel ?? R
Quote from: wootz on October 31, 2016, 03:06:08 AM
Will share impressions in a month or two.
Looking forward to it.
First, I don't have, and have never used a CBN wheel.
This topic comes up here every so often. They sound promising and I have read many reviews, but I have not purchased one simply due to their cost. There are many reviews and a LOT of information out there, so hop on the 'Net and start researching.
Search Google for things like:
tormek CNB grinding wheel
how long do CBN wheels last
types of CBN grinding wheels
CBN grinding wheel reviews
CNB grinding wheel durability
Here's what I can summarize from what I have read:
Be sure to get the electroplated version. You can also use the side of the wheel. Get the square edged version unless you have a specific need for a rounded edge.
Buy from a reputable dealer in case there are any problems with the manufacturing of the wheel.
Looking FW to wootz's CBN performance review in a month or two.
Pros:
They last a long, long time. Many reviews saying they many never need to replace it. "Why did I wait so long", that type of thing. One review spoke of 20%-50% savings over regular grinding wheels in constant duty, high speed grinding operation. Not sure if this was the electroplated version or not. I would guess the MTBF would be greatly increased in an ultra slow speed application like the Tormek. Occasional reports of the wheel getting dished in the center. Not sure if this was the electroplated version or not. Dished wheel replaced under warranty.
Even with high speed grinding they don't get hot. No need for water.
They are perfectly balanced and flat, and will remain so forever. No need to ever true the wheel.
Grit remains constant. No need to dress the wheel.
The diameter of the wheel will never change. One Kenjig will last forever!
They don't load up, and are non-reactive with steel.
Can be switched for use with both the Tormek and a bench grinder.
Lots of folks use them with the BGM-100.
Cons:
If the wheel is not perfectly in alignment with the control bar of the Tormek, the orientation of the control bar must be changed as the wheel perfectly square and flat and cannot be changed. While there is no need to ever true the wheel, it is at the same time not possible to do so to match the orientation of the control bar.
In the unlikely event of the wheel surface being damaged to the point of unacceptable performance it cannot be trued.
Unlike the Tormek, multiple wheels must be purchased to vary the grit.
When used with a regular bench grinder, there is the usual environmental air born particulate issue.
Cost. They are not inexpensive.
Very well done, Grepper. (I would expect no less from you!)
Like you, I do not have a CBN wheel. However, I do have a DMT diamond flat plate for flattening bench stones. It is a nice product, but, unfortunately, it has been overhyped in reviews. I made the mistake of believing the "flatten every stone in the shop" hype. It does a great job on water stones and India stones (aluminum oxide oil stones). It even finished flattening my grandfather's cupped Crystalon stone, but only with high casualties. Foolishly flattening that one inexpensive stone worn the diamond plate substantially, shortening its useful life considerably. The moral of this story is the flat plate is a great product for water and India stones. But, do not believe all the media hype.
I suspect CBN wheels are probably the same. If "forever" is rationally interpreted as for a long time, we will be happy. Frankly, if any grinding wheel gives several years of good service, I am content with the investment.
I had a specific set of expectations for the 3X wheels. I wanted them to perform OCCASIONAL use reshaping high speed steel turning tools at a reasonable cost. I purchased both 46 and 80 grit wheels for the project and found that just one, either grit, would be sufficient. At a cost of fifty US dollars, I feel the cost is reasonable. These met my need.
I believe at this point, a user should have a definite need in mind to justify the cost of a CBN wheel and that the wheel should be considered a very long term consumable item. A very active turner doing a lot of reshaping might be delighted with a coarser CBN wheel. He might be less happy with a finer wheel, which would be ideal for a knife sharpener. The cost involved should warrant careful thought.
I applaud Wootz for being our fearless pioneer. I look forward to his dispatches from the front.
Go, Wootz!
Ken
Quote from: Ken S on February 04, 2016, 12:42:22 PMGood preliminary testing, Wootz.
I really did not use my Tiger wheel enough to fairly comment. At the time, I was sharpening primarily chisels. Being 800 grit, it did not seem to cut as quickly as the SG graded coarse. That's understandable.
In considering the SG-250, it is only fair to remember that until November of 2008, the SG was the only grindstone for the Tormek. It was expected to work with all of the Tormek jigs and different kind of steel.It was expected to sharpen planer blades, including removing nicks. It was expected to reshape and sharpen turning tools, both carbon and high speed steel. It was expected so sharpen tools sized from small carving tools to axes. In conjunction with the leather honing wheel, it was expected to handle the whols sharpening process from grinding through honing and polishing. No dry grinding wheel, bench stone or sanding belt is expected to do so much.
In truth, the SG was not always a speedster at all of these things. Howbever, it did do them. It has also been expected to be long lasting. That's a tall order for any grinding wheel.
I am not surprised that the 800 grit wheel seems a useful adjunct for the Tormek. I have found the two Norton 3X wheels (46 and 80 grit) useful additions. Neither of the 3x wheels will ever be my general purpose wheel. They do help when I have a lot of grinding to do.
The SG grinding wheels are the old reliables which do most of my sharpening.
Ken
What are the Norton wheels you describe here that work with the Tormek? These may be the ticket for me to quickly reprofile edges for customers.
A basic internet search on "norton 3x grinding wheel" turns several hits. These have a larger arbor hole, so one has to do some adaptation of the bushings to fit the 12mm Tormek shaft.
There has also been a bit of discussion of these wheels elsewhere on the forum, so search in past messages. Ken has mentioned multiple times he drilled out PVC pipe for the bushings and used fender washers as flange washers, to fill the extra length on the Tormek shaft. I machined bushings from SS and flange washers from aluminum.
At one point, there were commercially available adapters, but I don't know where they were from. Searching forum posts may turn it up.
These wheels are trued using the Tormek truing tool. Again, this has all been discussed in various posts here on the forum. Look around.
Rick
Here is a link for the Norton 3X grinding wheels.
https://www.leevalley.com/en-us/shop/tools/sharpening/wheels-and-wheel-dressers/62012-norton-3x-grinding-wheels
The 3X wheels have both pros and cons. They cut fast. They work wet or dry. (I use them wet with my Tormek. I also have a six inch 46 grit wheel in my dry grinder.) As you can see in the link, they are inexpensive. On the con side, eight inches is the largest diameter. In reality, these eight inch wheels work with the T8 as well as any wheel worn to eight inches (200 mm). Norton supplies a set of reducing bushings from one inch down to 5/8". I cobbled a piece of 5/8" OD plastic pipe and drilled the ID from 7/16" to 12mm or an enlarged 31/64". While not toolmaker accuracy, it is within tolerance for initial rough sharpening.
The 3X wheels are not a perfect choice; they are very workable choices at low cost. They need a finishing wheel like the SG-250 to do the whole job. They will do "the heavy lifting". You don't need both grits. I started with the 80 grit.
Ken
Quote from: Ken S on February 21, 2023, 05:02:59 PMHere is a link for the Norton 3X grinding wheels.
https://www.leevalley.com/en-us/shop/tools/sharpening/wheels-and-wheel-dressers/62012-norton-3x-grinding-wheels
The 3X wheels have both pros and cons. They cut fast. They work wet or dry. (I use them wet with my Tormek. I also have a six inch 46 grit wheel in my dry grinder.) As you can see in the link, they are inexpensive. On the con side, eight inches is the largest diameter. In reality, these eight inch wheels work with the T8 as well as any wheel worn to eight inches (200 mm). Norton supplies a set of reducing bushings from one inch down to 5/8". I cobbled a piece of 5/8" OD plastic pipe and drilled the ID from 7/16" to 12mm or an enlarged 31/64". While not toolmaker accuracy, it is within tolerance for initial rough sharpening.
The 3X wheels are not a perfect choice; they are very workable choices at low cost. They need a finishing wheel like the SG-250 to do the whole job. They will do "the heavy lifting". You don't need both grits. I started with the 80 grit.
Ken
So if I'm understanding that item through Lee Valley comes WITH the adapter necessary to use it on the drive shaft for the Tormek?
No. The Norton wheels have a one inch bore and are supplied with one onch to 3/4" and 5/8" reducing bushings. The wheels are also one inch wide, meaning that they also require additional spacers to fit snugly on the Tormek shaft.
This can be accomplished in two ways. Rick, with machinist skills and tools, turned an adaptor himself. This is the preferred method. Any local machine shop can make up an adaptor for you. Just show them your Tormek and the wheel you want to mount.
My "Plan B" was to drill out a short piece of 5/8" Outside Diameter (OD) plastic water pipe to 12mm with my home shop drill press. Lacking a 12mm drill bit, I actually used a 31/64" bit and reamed out the hole a bit. In hindsight, I should have purchased a 12mm bit. 12mm fender washers provided an inexpensive fix to fill in the gap. My homemade method is adequately accurate for initial grinding, although it probably wouldn't pass muster with Rick.
The 3X wheels are not a perfect solution. The best solution is a Tormek DC-250 coarse diamond wheel. For occasional use, a very inexpensive 3X wheel may prove adequate.
Ken
Quote from: Ken S on February 27, 2023, 06:35:39 PMNo. The Norton wheels have a one inch bore and are supplied with one onch to 3/4" and 5/8" reducing bushings. The wheels are also one inch wide, meaning that they also require additional spacers to fit snugly on the Tormek shaft.
This can be accomplished in two ways. Rick, with machinist skills and tools, turned an adaptor himself. This is the preferred method. Any local machine shop can make up an adaptor for you. Just show them your Tormek and the wheel you want to mount.
My "Plan B" was to drill out a short piece of 5/8" Outside Diameter (OD) plastic water pipe to 12mm with my home shop drill press. Lacking a 12mm drill bit, I actually used a 31/64" bit and reamed out the hole a bit. In hindsight, I should have purchased a 12mm bit. 12mm fender washers provided an inexpensive fix to fill in the gap. My homemade method is adequately accurate for initial grinding, although it probably wouldn't pass muster with Rick.
The 3X wheels are not a perfect solution. The best solution is a Tormek DC-250 coarse diamond wheel. For occasional use, a very inexpensive 3X wheel may prove adequate.
Ken
What is the price I should expect to pay at a machine shop for this? Seems inexpensive enough but I have no idea what labor might truly be at a place like this.
I don't know.I would suggest you talk with a couple machine shops and get estimates. You can always go with the plastic pipe option.
Ken