C.B.N. coated for T7

[Ken S]

This would be an excellent opportunity for those members of the forum who have had good experiences with the planer jig to post. If you have had a good experience with this jig, please post. We want to hear from you.

Ken

[grepper]

I think I rather agree with Ken when he said, "..is the problem the jig or the mismatch of grinding wheel and exotic alloy?"  I'm guessing it's the latter. 

I don't have a planer and so I can't speak for the jig, but I've had similar experience with very hard knives.  Steel even approaching RHC 60 is very difficult to sharpen on the Tormek.  It's not that the jig is working differently, just that the steel is so hard the wheel just has a very hard time cutting it.  You can grind away for a long time with little results.  It can be very frustrating.

CBN is made for hard alloys and will cut stuff AO and the like won't touch.  I suspect, Rob, CBN might be what you have been looking for to do planer blades.  I don't have one, but that is what the wheels are supposed to excel in cutting and what they are made to do.

Search around in Netland and I suspect you will arrive at that same conclusion.  You might contact one of the manufactures and explain the issue and see what they say.  It would be cool if you did, or better yet if you got one so you could let the rest of us know. 

[Rob]

I think we're all agreeing with Ken that there's nothing wrong with the jig.  I've stated this many times.  The jig is brilliantly conceived and engineered.  It positions the blade in exactly the right conditions and then keeps it there throughout the grind.  It protects the necessary precision required for the balance of planar blades really well as that setting is baked into the design.

The problem was never anything to do with the jig, twas always the inability of the grinding to cut the steel successfully.  So you're right, if a grinding wheel existed that didn't require truing while simultaneously cutting more aggressively, then they would probably do it.  CBN does appear to be such a technology if the hyperbole is accurate.  However, it is stunningly expensive when your economic case is cast in a domestic setting because lets say the wheel costs £200.  If I send my planar blades to a service they cost around £25.  So I could get 8 sharpenings done externally before my CBN has paid for itself on those grounds.  Well I haven't sharpened my planar knives 8 times in the last 5 years :-)  Once a year would be about normal and maybe twice if I have a tricky project in oak to do which I am wont to do every now and then.

So for my needs, there is no economy of scale.  In an industrial setting it would be a no brainer.

But that wasn't really where Ken was going...Ken is asking forum members to come up with "good news" about experiences with the planar jig so he can stick it to me for operator error :-) (I'm joking Ken).

Seriously though, he does have a good point because there aren't many of us who use the planar jig so experience is very thin on the ground.  It is possible (I guess) that technique is missing but in fairness to my process I spent 8 hours solid grinding these knives and that was after reading and re-reading the procedures plus all of Ionut's posts and I know for certain I had it setup exactly as designed.  The problem was nowt to do with the jig, the wheel just wont cut my steel.  And we debated this with Jeff at the time and even he (Mr Confident himself) was very reticent to overly promote the efficacy of the jig/wheel combo.  His suggestion was to try the blackstone but counter to that, our very own Ken has got disappointing results in quite well controlled and objective testing where the blackstone didn't remove as much steel as the SG!!

So in summary:  in my own mind the CBN approach sounds very promising indeed but the current cost makes it inaccessible.

[Ken S]

I think this has been an interesting topic. It is obviously about non Tormek products being used on the Tormek. We have expressed doubts and concerns about the present effectiveness of  the Tormek system with coarse grinding and hard steels. Admittedly these are beyond the original scope of the Tormek. However, the scope of the Tormek has widened over the years, without losing sight of its original purpose.

Despite the constructive criticism, I do not see us selling our Tormeks, nor do I expect to see a rush in CBN or Norton 3X grinding wheel sales.  Hopefully Sweden has been reading this topic and has become more aware that the party faithful would like a more efficient means of dealing with heavier grinding and harder steels. I believe this kind of work is within the present scope of the Tormek when supplemented with third party grinding wheels. I believe Tormek will continue evolving and eventually offer its own wheels for these tasks.

Most of us do not require these specialized grinding wheels. I do not believe many of us will actually purchase CBN wheels, although the 3X wheels may prove most effective for some of us. It may be that Tormek may decide that the business interests of the company are more effectively served by using third party products for items of limited demand. That is certainly understandable. As the cost of CBN wheels declines, Tormek may decide to enter the ring. I have no inside information.

It is comforting to know that should the need arise for me to sharpen planer blades or hard steel allows that my Tormek can be adapted to these tasks while still providing the same hallmark cool dust and spark free grinding.

Ken

[Herman Trivilino]

I think the SB grindstone was introduced to address the issue of the harder exotic steels, but it just doesn't do the job as well as cBN.

Ken, I agree that the problem is not the jig. But I don't agree that the sharpening of exotic hard steels is necessarily occasional. What if someone buys the planar blade jig and the only planar blades they own are of the harder steel variety?

Rob, I agree that the problem is the way it's marketed. Have you tried the SB grindstone on these harder planar blades?

[Ken S]

Good points, Herman. For someone who regularlyused a planer (and jointer), it would certainly not be an occasional need. If I was in that circumstance, I might try the low cost 3X wheel first, but I would be prepared to purchase a CBN wheel.

I think the marketing people need to go back to the drawing table with customer expectations. While it well known that I anm a Tormek fan, reading the comments about sharpening hard alloy steel planer blades for the times posted does not excite me. Nor does the tactic of subcontracting to a dry grinder.

Ken

[Rob]

I think the SB grindstone was introduced to address the issue of the harder exotic steels, but it just doesn't do the job as well as cBN.

Ken, I agree that the problem is not the jig. But I don't agree that the sharpening of exotic hard steels is necessarily occasional. What if someone buys the planar blade jig and the only planar blades they own are of the harder steel variety?

Rob, I agree that the problem is the way it's marketed. Have you tried the SB grindstone on these harder planar blades?

That's my only weak spot in all of this.  I confess that I bought the blackstone specifically to address the inability of the SG to sharpen my planar knives.  It took 8 hours as I posted above and I'm not exaggerating with that I'm being quite literal.  After about 2 hours I gave up on regarding the SG with the sp650 because it glazed over again in seconds.  Eventually I started using the diamond dresser to true the wheel because it was the only way to keep it cutting.  Now it would glaze after a couple of minutes.  On I struggled for hours until it had got the job sort of done.  By the end of course the wheel was a lower diameter and that threw the jigs settings out.

The procedure was so frustrating that I haven't had the will to try it again with the SB and since the SB is the right wheel for HSS and I began turning at about this time I had a use for it anyway. So I should cycle back and finish the experiment with the blackstone but I'm pretty sure it wont make any difference.  But that's anecdotal and not reasonable.  Finding the time to do it again might be a tad tricky with the family circumstances.

[Ken S]

As promised, here is an answer to the question from D-way tools about rust with CBN wheels:

Ken,
Rust is not a problem with wheel, but the bushing can rust, a little oil on it before installation fixes that.
Should last you a lifetime, I have some I have been using for seven years and are still going.
I am not sure anything is fast with Tormek, but the 180 is the most popular.

Dave Schweitzer

Dave is referring to the bushing which adapts the CBN larger bore to the Tormek 12mm bore. Apparently the bushings are not stainless steel. This seems like a problem, if it is an actual problem, which could be easily and relatively inexpensively remedied with a stainless bushing. Any good local machine shop should be able to fix that.

The second question was asking Dave for a SWAG of CBN wheel life. The third question was, assuming a part time Tormek user would probably only purchase one grit, which would be the most practical.

My sharpening needs have almost no high speed steel at present. I have found that the SG wheel does fine (for me) with the occasional high speed drill bit. I find this topic fascinating, but probably will not be the first to purchase a CBN wheel. (The tormek junkie in me can't quite get past the thrifty old New England Yankee.)

[SharpenADullWitt]

I think this has been an interesting topic. It is obviously about non Tormek products being used on the Tormek. We have expressed doubts and concerns about the present effectiveness of  the Tormek system with coarse grinding and hard steels. Admittedly these are beyond the original scope of the Tormek. However, the scope of the Tormek has widened over the years, without losing sight of its original purpose.

Despite the constructive criticism, I do not see us selling our Tormeks, nor do I expect to see a rush in CBN or Norton 3X grinding wheel sales.  Hopefully Sweden has been reading this topic and has become more aware that the party faithful would like a more efficient means of dealing with heavier grinding and harder steels. I believe this kind of work is within the present scope of the Tormek when supplemented with third party grinding wheels. I believe Tormek will continue evolving and eventually offer its own wheels for these tasks.

Most of us do not require these specialized grinding wheels. I do not believe many of us will actually purchase CBN wheels, although the 3X wheels may prove most effective for some of us. It may be that Tormek may decide that the business interests of the company are more effectively served by using third party products for items of limited demand. That is certainly understandable. As the cost of CBN wheels declines, Tormek may decide to enter the ring. I have no inside information.

It is comforting to know that should the need arise for me to sharpen planer blades or hard steel allows that my Tormek can be adapted to these tasks while still providing the same hallmark cool dust and spark free grinding.

Ken

To me, I see the CBN quite similar to how I see  a bench grinder, which Tormek does sell a kit to use their jigs on.  One thing to possibly speed up initial sharpening/shaping/chip removal, verses taking a while on the Tormek.  The other direction, and I couldn't find the wheel, was a finer grain CBN, compared to the SJ wheel for stuff like the knives some chef friends have (frequent touch ups).  I remember reading about a finer grit CBN somewhere.
Those 3x wheels are great for a lot of metal removal (think punch dressing/sizing for garage/mechanical work) and I would like to try a CBN for that (keeps auto fluids away from the Tormek stone).  I don't think there is any issue with that (no warnings from them yet), as that tech advances, I could even see Tormek, eventually deciding to sell one if it was deemed useful enough. 

[Ken S]

I agree that CBN wheels will eventually be available in more and finer grits. I suspect this will be sooner rather than later, if not already.

I bought my six inch dry grinder from Sears in 1972. Admittedly it is no Baldor, but it has served my home needs well. One side has an 80 grit white wheel which has not been used since I bought my Tormek. The other wheel is a 3X 46 grit. I bought it to remove major mushrooming from two splitting wedges for a friend. It really does the job, and with a chunky splitting wedge head overheating is not a problem.

I tried this wheel with the Tormek and was pleased enough to purchase two eight inch 3x wheels. (46 and 80 grit. Either one would suffice,) Used this way, they offer the benefits of Tormek's water cooled dust and spark free grinding with much of the speed of dry grinding. Since there is no Tormek wheel of this coarseness, this is a workable low cost option for things like reshaping turning tools or the initial rough sharpening of planer blades with nicks.

Ken

[SharpenADullWitt]

Ken, is the Craftsman a square frame grinder? (right time period)

If so, don't knock those, as they were US made and by forums I have been on, quite comparable, even better cost/value to a Baldor, and I have one of each.

[Ken S]

SADW, that's the one! 3450 RPM, half a horse power, built in flex light. As I recall, it was$29.95 on sale from 49.95. I bought two, one for my father-in-law. My son-in-law uses it now. Both are still in service since 1972. not a bad service record.

Ken

[grepper]

There are CBN emulsions for belts and leather wheels are available from a variety of sources.  Here is an example of one source.

0.1 micron – 80 micron
http://www.jendeindustries.com/products/sharpening-products/marble-basins/product/198-cbn-emulsions-from-ken-schwartz

Here's another:
4 Micron: 4,000 grit
1.5 Micron: 13,000 grit
.5 Micron: 60,000 grit
.1 Micron: 160,000 grit
http://www.kmesharp.com/cbnemulsions.html

Spray on too:
http://www.oldawan.com/sharpening-supplies/cubic-boron-nitride-cbn-sprays/

[grepper]

I agree that CBN wheels will eventually be available in more and finer grits. I suspect this will be sooner rather than later, if not already.

Now available in Super Fine 350/400 grit and Fine 170/200 grit (ASTME)

https://www.woodturnerscatalog.com/p/97/5784/Raptor-8%22-CBN-Fine-Sharpening-Wheel-with-Arbor-Bushing

[Ken S]

Interesting post, Grepper. A couple things caught my eye:

"Warning: Grinding non-heat treated steel such as carbon steel, aluminum and other soft metals will cause irreparable damage to the CBN wheel."

While the CBN wheels might be the greatest thing since sliced bread for harder steels, I am not ready to discard my SG wheel for carbon steel, which is the bulk of my sharpening. The new EZYlock quick change shaft has certainly made multi wheels practical. Cost may be a constraint, but switching on a Tormek certainly presents no difficulty.

The other thought is the need for a common or at least translated chart of stone coarseness or fineness. When I see "superfine" represented as 350/400 and "fine" as 170/200, we definitely have apples and oranges with numbers. I routinely try to denote measurements in both "English" and metric. I wish coarseness was expressed that way. When Tormek's 200 grit of the SG when graded coarse is considered coarse and 1000 is considered fine, to be followed by the leather honing wheel, given the mystical grit number of 6000, there is confusion.

Most of the websites I have seen for CBN wheels do not seem quite ready for prime time for Tormek when it comes to bore bushings. Even D-way, which seems the most Tormek friendly, doesn't quite hit the mark. I like the eight or ten inch option they offer. The 1 1/2" (40mm) width is closest to the Tormek. It is identical with the width of the SG200 wheel for the T4. I think they are almost there, but would prefer a stainless 12mm bushing to prevent rust. In fact, when the industry decides to get serious about providing CBN wheels for Tormek, I would like to see the wheels made with 12mm bores requiring no bushing, just like Tormek's wheels.

I hope Allen Simpson chimes in. His tool and diemaker background would be invaluable in this discussion. I can see the value of a CBN wheel for someone who sharpens planer and jointer blades or who does a lot of turning. It would be nice if one grit would suffice. This one wheel approach may not be practical. I am questioning, not pronouncing. Again, we must balance speed with smoothness of finish with consideration of cost.

I know a veteran Tormek user who finishes his planer blades with a small microbevel ground with the SJ 250  4000 grit Jananese wheel. That might not be practical for day to day working, but, for high quality work, it would be sweet.

Some have questioned using high speed wheels with the Tormek. I may be in the minority, but it seems like a nice balance to me. The coarser grit wheels cut faster, keeping the time involved to a reasonable amount. I especially like not having to perform routine maintenance on the wheel. The slower speed and water cooling of the Tormek keeps everything well controlled, cool and free of metal grinding debris.

Ken