Thoughts on the Diamond Wheels vs. Traditional Grindstones

[RichColvin]

Hello Rich
Thanks for posting the pic - worth a thousand words!!   I am trying to find a 1200  Grit diamond wheel  (DE-250).  Apparently a production problem. Anyone heard of any suppliers who are stocking them at this point??

Thanks
George

George,

Sure, no problem.  I took the pic as it made me think of the cars with serious upgrades ... you know, like the Yugo with a V8, 5.7 L Hemi engine it !!

Kind regards,
Rich

[cbwx34]

Hello Rich
Thanks for posting the pic - worth a thousand words!!   
...

And notice that EzyLock setup.

[Jeff Thurwatcher]

My wheels arrived today, haven't used any of them yet. They are heavy.

BTW a bottle of anti-corrosion concentrate comes with each wheel so now I have 5 bottles of it.

[Ken S]

Welcome to posting, Jeff.

Remember to use very light grinding pressure with the diamond wheels. I think you will enjoy using them. I like the continuous cutting sound and feel that does not decline or need to be frequently refreshed. Keep in mind that, like CBN wheels, there is an initial break in period when the wheels cut more aggressively. This is short.

Enjoy.

Ken

An inexpensive children's plastic medicine graduate/spoon from the pharmacy department, graduated in milliliters, simplifies using the ACC.

[Pastor_Zatx]

4. Unlike CBN wheels, these can be used for sharpening high carbon steels.

Why do you say that CBN cannot be used with high carbon steels?

[GKC]

This is a common caveat with CBN and diamond wheels, the concern being that some (merely) high carbon steels are not inherently hard enough or haven't been hardened enough, with the result that they could clog ("gum up") the abrasive array on the surface of the wheels. 

However, I don't find the term "high carbon steel" very useful in this context.  It is true that CBN and diamond wheels excel on high speed steels and the newer super hard steel alloys, which pose no risk of clogging the wheels. But some high carbon tool steels can be quite hard and users report that they do not harm their CBN wheels.  Also, some who have experienced clogging have found that the wheels can be cleaned up by grinding some high speed steel on them.

But as Ken is wont to remind us, the standard Tormek grindstone is excellent at high carbon steel, so you don't need to put your exotic wheels at risk.

Gord 

[Pastor_Zatx]

This is a common caveat with CBN and diamond wheels, the concern being that some (merely) high carbon steels are not inherently hard enough or haven't been hardened enough, with the result that they could clog ("gum up") the abrasive array on the surface of the wheels. 

However, I don't find the term "high carbon steel" very useful in this context.  It is true that CBN and diamond wheels excel on high speed steels and the newer super hard steel alloys, which pose no risk of clogging the wheels. But some high carbon tool steels can be quite hard and users report that they do not harm their CBN wheels.

Also, some who have experienced clogging have found that the wheels can be cleaned up by grinding some high speed steel on them.

But as Ken is wont to remind us, the standard Tormek grindstone is excellent at high carbon steel, so you don't need to put your exotic wheels at risk.

Gord

Thank you for this response. I have an ever-increasing collection of knives that include high-carbon and stainless steels that include 52100, HAP 40, REX 45, D2, M390, S30V, S90V, S110V, CTS-204P, CV20, and others I don't remember at the moment. I've sharpened these with CBN rods and stones without any damage to the sharpening medium so thought it might be something unique to the Tormek CBN wheels. I know that CBN and diamond are sensitive to pressure and heat (though heat is less of a factor with CBN) so I'm careful to avoid both when sharpening these steels.

I'm in the "research" phase of my Tormek purchase and wanted to make sure I didn't buy something in error.

Thank you again.

[RichColvin]

Jason,

Gord is exactly correct.

By the way, I believe this is why Tormek was "late" to the game of replacing their traditional grindstones.  They pursued a diamond wheel approach which works extremely well when kept cool.  CBN is a better alternative if grinding at high speeds or pressures.  Since neither of those apply on the Tormek diamond wheels, it was a smart choice by Tormek.

The notes I have about CBN and diamond wheels on my SharpeningHandbook.info site are :

CBN stone notes

• These are not recommended for tools with high carbon steel. Those and other softer steels can "gum up" the wheel's surface. That said, a person I cannot remember has stated that grinding high speed steel (HSS) on the CBN wheel will clear the "gumming".
• Resins accrued on tools when turning wet woods can also gum up the grit. Trend lapping fluid was recommended (on an AAW forum) by Reed Gray (aka, "Robo hippy") for cleaning the wheel.

Diamond stone notes

• Do not use diamond stones (unless they are cooled - e.g., with water) for tools with ferrous metals. Hot iron molecules can dissolve diamonds, quickly eroding the surface.

Kind regards,
Rich 

[Ken S]

The difference between Tormek and third party grinding wheels is that the Tormek products are specifically designed to work on the Tormek. That is not to say that other products, such as CBN wheels, will not work or work very well with the Tormek. They are just primarily designed for other purposes, generally high speed dry grinding. Look at the vendor's websites. You will often find well done videos showing turning tools being sharpened with high speed dry grinders. These wheels function very well for this intended purpose. I have three CBN wheels and really have no complaints with them. (Mine, unlike some, can be used wet.) I just prefer the Tormek diamond wheels. They are designed to be used wet, and the 12mm bore is by design, not an after thought.

Ken

[GKC]

Ken, I am wondering if you experience different results with your diamond wheels compared to your CBN wheels.

About "designed in" wet use and 12mm bores, I got my 250mm CBNs to use dry, but I now also use them wet with good results.  I don't think of the 12mm bore in the middle of my wheels as any less designed into the wheels than those in a Tormek wheel.  So I don't see the significance of those points.  And as with you (or at least as I take it from your comment in the thread started by Pastor Zatx) I don't mind (and sometimes want) the hollow grind, so I am happy to work on the circumference of the wheel.  And the flat grinding option on the side of the diamond wheels would not be my first choice for flat sharpening tasks when I have them.

So, I keep wondering about results: is there a difference between CBN and diamond in the Tormek application? Maybe no one has done a comparison and the data aren't there.  But it could matter to some, because the 250mm CBNs are about $180 and the diamonds are about $330.

Gord

[RichColvin]

Wootz is probably the best to answer this. 

Kind regards,
Rich

[madeiranlotuseater]

Hi there,

I'm new to this community.

My plane irons and chisels are all A2 steel.  The plane irons some 4.5mm thick.  Obviously repairing nicks in these blades means that a lot of metal needs to be removed.  I've tried the Blackstone but, whilst a fine stone, takes forever to grind away A2.

My question is, will the new Diamond Stones from tormec be up to the job? Never cheap in the first place.  More expensive still when I bought a Blackstone wheel. These diamond ones??? 

[RickKrung]

Hi there,

I'm new to this community.

My plane irons and chisels are all A2 steel.  The plane irons some 4.5mm thick.  Obviously repairing nicks in these blades means that a lot of metal needs to be removed.  I've tried the Blackstone but, whilst a fine stone, takes forever to grind away A2.

My question is, will the new Diamond Stones from tormec be up to the job? Never cheap in the first place.  More expensive still when I bought a Blackstone wheel. These diamond ones???

Welcome to the forum, Charles. 

I have found the Tormek coarse diamond wheel (DC250) wanting when a lot of steel needs to be removed.  When I am faced with needing to remove a lot of metal, I go to a more traditional grindstone, the Norton 3X, which is ceramic alumina designed for heavy metal removal.  While they are designed to be used at high speed on a traditional grinder, but by adapting mounting bushings to 12mm, they can be used on the Tormek at low speed with water cooling.  They function the same as wheel worn down to about 200mm. 

The Norton 3X wheels are available from a number of suppliers.
Lee Valley
http://www.leevalley.com/us/wood/page.aspx?cat=1,43072,43080&p=62012


Sharpening Supplies
https://www.sharpeningsupplies.com/Norton-3X-Blue-Grinding-Wheel-I-Grade-P37.aspx

At around $60 US, they are a very economical alternative.  I received mine used from Ken S.  Ken drilled out a piece of 1/2" PVC pipe, as I recall, to make a bushing that fit the 12mm Tormek shaft, along with the bushings provided with the wheels to fit a 5/8" shaft.  I machined stainless steel bushings that mated the 1" arbor hole with the 12mm Tormek shaft.  The wheels are 1" wide, so need spacers between the inner Tormek spacer on the inside and/or the locking nut on the outside.  Ken used 12mm fender washers.  I machined flanges out of aluminum. 

D-Way Tools sells a bushing kit to adapt 1" arbor hole CBN wheels to 12mm shafts.
http://d-waytools.com/cbn-grinding-wheels/bushing-kits-for-cbn-grinding-wheels/.  These are designed for wheels 1-1/2" wide so you would need to cut then down for the 1" wide Norton wheel. 

Rick

[madeiranlotuseater]

Rick,

Many thanks for your information.  I left my Karl Holtey plane irons in store for two years and the A2 suffered very badly.  So much so that I decided to order two new blades for my 98s. What an expensive mistake.  Fortunately the planes are made in stainless steel.

[Ken S]

Charles,

Are you familiar with these rust erasers? I have a set that I use quite frequently, and thought it might revitalize your Holtey blades.

http://www.leevalley.com/us/garden/page.aspx?p=10509&cat=2,42194,40727

Ken