Opinions on Rocks/Stones for a Cats Claw Sharpener

YellowHammer · March 20, 2014, 09:55:48 PM

I'm kind of getting the hang of my Cats Claw sharpener, and I've been using the blue rocks from Cooks. I've been sharpening a lot, catching up on a stockpile of dulls, and am significantly wearing down my rock. I've got a couple spares, but it got me thinking at what options were available, and started searching old posts for info.
Is there a better choice than what I'm using? Something that cuts faster or lasts longer? What about the Ruby from suffolk? I've read that some folks prefer that. Or should I try a black rock from Cooks or WM? What about a CBN on a dry grinder, how long does it last?
I have found a lot of choices out there, all claim to have advantages, I just want to avoid having to buy one of all of them to try out.
Thanks,
YH

GF · March 20, 2014, 10:03:58 PM

I used to use the blue stones from Cooks they are pretty good. Seems like they wear pretty quick and lose there shape. I tried a ruby stone from Suffolks and was really impressed with it. It holds it shape a lot longer and last a lot longer, and does not discolor the tooth tips like a hard stone normally does. Just last month I bought three more ruby stones from Suffolk, and I dont think I will go back to the blue stones. I think if you try the ruby you will like it much better. Just my two cents.

Delawhere Jack · March 20, 2014, 10:58:34 PM

Quote from: YellowHammer on March 20, 2014, 09:55:48 PM
.. and am significantly wearing down my rock.

How are they wearing down? From grinding bands, or from having to be re-profiled?

I find that the largest portion of wear on my stones comes from having to re-profiling them. Usually they need re-profiling because the edge of the rock that grinds the face of the tooth gets rounded over. The portions that contact the gullet and the back of the tooth are barely worn at all. Is this what you are encountering?

bandmiller2 · March 21, 2014, 07:11:35 AM

I use the blue and ruby ceramic stones and like both. If your wearing them down fast your dressing them too much, just an occasional swipe with the abrasive block. I have a diamond grit dresser and only use it to shape the wheel and rarely after that. Light cuts and you will get good band life and long wheel life. Frank C.

Peter Drouin · March 21, 2014, 07:14:08 AM

You need a oil bath to use a CBN wheel [It cleans it]

petefrom bearswamp · March 21, 2014, 08:18:44 AM

I have been using the CBN wheel from Diagrind in Ireland, but it is on my older drag WM sharpener.
I cool/lube with some old light weight hydraulic oil I had kicking around.
I assume from reading the above that the Cooks sharpener has no cooling/lube apparatus?
Had a ruby stone from Suffolk a few years ago but it was out of round and I junked it.

ely · March 21, 2014, 09:05:45 AM

I use the blue ones from cooks saw and I have had good luck with them so far. I used one pretty much up in about a month back in 04 when I first got the cat claw, then I purchased two new blue rocks and I still have one new one left today.
after I figured out how to run the sharpener I barely use any rock to speak of... and I also rarely reshape the rock like I used to. if you are using that much blue rock you are grinding way too aggressively. and if you grind aggressive you certainly will not like the black rock from cooks, as I understand they are way softer than the blue.
im pretty happy with the blue , but I may try the ruby rocks in the future, I hate to miss out on a good thing.

Chuck White · March 21, 2014, 09:23:08 AM

The Cat Claw sharpener is a dry grinder, no water, no oil, nothing is used to cool the grind, just don't grind to heavy or you'll burn your blade!

I have used the blue rocks on my Cat Claw since day one!

In fact when the sharpener arrived, it had a blue rock installed and shaped to sharpen my Wood-Mizer 10° blades!

I get a lot of sharpening with each rock that I install, so I can't complain.

Basically, I shape a new rock when installed, then just clean it up lightly, just to get the crud out of the surface of it!

I got my Cat Claw in June of '09 and have used and replaced 3 rocks, so I feel that I've gotten good life from the blue rocks!

I really like the blue rocks, I only wish I could find something comparable locally, only because it would save me on shipping!

losttheplot · March 21, 2014, 11:27:39 AM

How many sharpenings should a person be getting from a rock ?

I'm still on my first one, and so far have 118 and I would expect to get somewhere close to 150.

I used up quite a bit getting the hang of using it, and I often send the band around more than once.

I find I need to clean the rock often or else the tips of the teeth get burnt.

The outfit that I used to use for sharpening has a cat claw, they have enlarged the shroud that covers the rock and are using the bigger brown rocks from wood-mizer.

LTP.

36 coupe · March 21, 2014, 07:08:16 PM

I have used Norton wheels for 40 years on my planer knife grinder.Hard steel needs a soft wheel.Try 32. and 36 Norton wheels

Chuck White · March 21, 2014, 08:52:42 PM

Quote from: losttheplot on March 21, 2014, 11:27:39 AM
How many sharpenings should a person be getting from a rock ?

I'm still on my first one, and so far have 118 and I would expect to get somewhere close to 150.

I used up quite a bit getting the hang of using it, and I often send the band around more than once.

I find I need to clean the rock often or else the tips of the teeth get burnt.

The outfit that I used to use for sharpening has a cat claw, they have enlarged the shroud that covers the rock and are using the bigger brown rocks from wood-mizer.

LTP.

I don't know how many sharpenings you'll get from one rock, there are so many variables!

I can tell you that I have sawn over 300,000 board feet of lumber with my resharpened blades and I'm now on my 4th rock.

YellowHammer · March 21, 2014, 10:05:02 PM

Quote from: ely on March 21, 2014, 09:05:45 AM
I use the blue ones from cooks saw and I have had good luck with them so far. I used one pretty much up in about a month

That's pretty much what has happened to me. I have been doing a lot of learning and experimenting and my rock is suffering. Tim Cook and I had a good phone conversation, (turns out his brother only lives a little ways away) and he gave me some excellent tips. In the end, I ordered some new rocks from them, but then started wondering about what other folks were using, and if anything is better. Since I'm still going up the learning curve I don't have a feel for how long the rock should last. Also, since people use the Cats Claw to sharpen bands commercially, or otherwise more that I would ever do, I am curious what you guys use. By the way, I would never have believed how good a Cats Claw sharpened and set blade cuts, even if its not a SuperSharp profile.

Speaking of learning, I have to generally take 2 to 3 times around to get a clean, sharp band. Is this normal?
Thanks for all the input and advice,
YH

customsawyer · March 22, 2014, 04:46:31 AM

I use the ruby rocks from Suffolk. I send my blade around 3 times unless it has hit a nail or some such as that then I will send it around 4-6 times to clean up the damaged teeth.

bandmiller2 · March 22, 2014, 07:46:01 AM

Hammer, my bands go once around the mulberry bush unless they have hit something. If a band is replaced before it gets dull once will touch them up to perfection. Of course others mileage may vary. Frank C.

5quarter · March 22, 2014, 08:05:14 PM

Yellowhammer...One the one hand, if you are having to make multiple passes around the grinder, you may be running your blades too dull. on the other hand, you may not be getting a sharp blade until the 2nd or 3rd pass because your grind is too light to get a squared edge on your tips. I'm in the multiple light grinds camp myself. I noticed some time ago that my freshly sharpened blades were not as sharp as they should be. I got out a large, 8x magnifying glass to really examine the tips. sure enough, I was not squaring the outside edges of the blade tips on the first pass. a second pass made all the difference in the tip profile. Just my observations.

backwoods sawyer · March 23, 2014, 12:39:03 AM

I agree with having good magnification as being the deciding factor on how many passes it needs to make, and take a close look at all surfaces, use plenty of light as well.

Peter Drouin · March 23, 2014, 08:58:08 AM

The outside top point will have a shiny spot on it if not sharp. Needs to be as sharp as a pin. I find you can't cut frozen hemlock flat unless it's perfectly sharp.
This year was a bear with the cold.

YellowHammer · March 23, 2014, 08:13:26 PM

I'm thinking of getting one of the magnifying lenses on an arm to make it easier to see the details. Here is a closup picture of a tooth that seems to be about as sharp as I can get it. So I used the Cooks blue rock for this, and noticed that the grit of the rock leaves little grind marks in the tooth. I assume these are normal and OK. Also, I notice a little burr on the very tip of the tooth left over from the grind rock. On a knife, this burr would be removed with a finer grit stone or by honing, but I'm thinking that a final, light polishing pass might remove it. On the other hand, I don't even know if matters in a real sawing situation.
YH

bandmiller2 · March 23, 2014, 08:29:00 PM

The log takes care of those little burrs. I have one of those rigs the doctor looks in your ear with, magnifies and lights the tooth. Frank C.

Peter Drouin · March 23, 2014, 08:54:34 PM

Quote from: YellowHammer on March 23, 2014, 08:13:26 PM
I'm thinking of getting one of the magnifying lenses on an arm to make it easier to see the details. Here is a closup picture of a tooth that seems to be about as sharp as I can get it. So I used the Cooks blue rock for this, and noticed that the grit of the rock leaves little grind marks in the tooth. I assume these are normal and OK. Also, I notice a little burr on the very tip of the tooth left over from the grind rock. On a knife, this burr would be removed with a finer grit stone or by honing, but I'm thinking that a final, light polishing pass might remove it. On the other hand, I don't even know if matters in a real sawing situation.
YH

I would not look at the face just the top of the tooth, Can't see it in the pic. I use a halogen light hanging from the ceiling 2' away from the blade. For me, more light is good, It will make the shiny spot shine.
For me, grind the back of the tooth to get the thickness of the blade back then the face to get it sharp. The blade will where the corners back all the way to the back of the tooth. So you can grind the face all the way back till you get the thickness back or the easy way is to grind the back of the tooth down and the gullet too [ to keep the tooth height] and get the face at the same time.
My blades are 55 thousand, My blades will not be sharp till I get that 55 back.
I hope I helped

bandmiller2 · March 24, 2014, 08:09:12 AM

As with most sharp edged tools if you can see the edge its dull, I look but learn more by feel. Frank C.

LeeB · March 25, 2014, 02:09:39 AM

If you use the articulated magnifying glass with a light, make some kind of cover for it. The dust and filings will settle on it and have scratched up beyond use in no time.

YellowHammer · March 25, 2014, 07:40:54 AM

Quote from: LeeB on March 25, 2014, 02:09:39 AM
If you use the articulated magnifying glass with a light, make some kind of cover for it. The dust and filings will settle on it and have scratched up beyond use in no time.

Good point. I'm going to start looking for one of those magnifying ohthalmoscopes like Bandmiller2 uses.
YH

jclvsall · March 25, 2014, 08:44:56 AM

this is the otoscope that we use. Great little bugger. AAA battery lasts forever with the LED.

Search Amazon for "dr mom otoscope" I can't post a link on here correctly.

Brian

DeepWoods · March 25, 2014, 09:43:00 AM

Is this the one? Amazon had several versions at various prices. I use a lighted magnifying glass to see the tooth profile to determine how sharp an edge I grind. Usually at least a couple times around, maybe three if needed.

http://www.amazon.com/Original-Doctor-Mom-Otoscope-otoscopes/dp/B000ITD3RA/ref=sr_1_4?ie=UTF8&qid=1395754322&sr=8-4&keywords=dr+mom+otoscope