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
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.
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?
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.
You need a oil bath to use a CBN wheel [It cleans it] :)
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.
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.
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!
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 have used Norton wheels for 40 years on my planer knife grinder.Hard steel needs a soft wheel.Try 32. and 36 Norton wheels
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.
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
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.
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.
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.
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.
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.
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
(https://forestryforum.com/gallery/albums/userpics/21488/Tooth_Face.jpg)
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.
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
(https://forestryforum.com/gallery/albums/userpics/21488/Tooth_Face.jpg)
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 :)
As with most sharp edged tools if you can see the edge its dull, I look but learn more by feel. Frank C.
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.
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
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
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
Ideally, you want that edge to "stand up". When a sharp knife gets dull, its because the edge has laid over to one side or the other. honing should not remove material, just bring the edge back in line with the blade body. since you can't really "hone" the tips of the teeth, you have to grind your profile in such a way that the tip is ground straight across it's full width as Peter says, and that the leading edge of the tip has not rolled back. it is as much art as science to get your sharpener and technique dialed in to the point where you get razor sharp tips every time, but I think you're almost there. Peters right on the money when he says to grind the back to get the tip back to full thickness. the face grind should be just barely enough to remove the burr from grinding the back and establish that "invisible" edge. in your photo, I can't tell whether the edge is standing up or not. if that burr doesn't come off easily with your fingernail, it's not a burr, but overheated edge material left over from grinding the face too heavy. sending it around once more very lightly should clean it up. your determination to get the sharpest possible blade will really pay off, not just in quality and production rate, but in the increased confidence in your ability to consistently cut great lumber.
Quote from: 5quarter on March 25, 2014, 09:48:04 AM
Ideally, you want that edge to "stand up". When a sharp knife gets dull, its because the edge has laid over to one side or the other. honing should not remove material, just bring the edge back in line with the blade body. since you can't really "hone" the tips of the teeth, you have to grind your profile in such a way that the tip is ground straight across it's full width as Peter says, and that the leading edge of the tip has not rolled back. it is as much art as science to get your sharpener and technique dialed in to the point where you get razor sharp tips every time, but I think you're almost there. Peters right on the money when he says to grind the back to get the tip back to full thickness. the face grind should be just barely enough to remove the burr from grinding the back and establish that "invisible" edge. in your photo, I can't tell whether the edge is standing up or not. if that burr doesn't come off easily with your fingernail, it's not a burr, but overheated edge material left over from grinding the face too heavy. sending it around once more very lightly should clean it up. your determination to get the sharpest possible blade will really pay off, not just in quality and production rate, but in the increased confidence in your ability to consistently cut great lumber.
Thanks 5quarter for agreeing with me on this . I won't go into how important it is for Coolant. :)
Yeah Deepwoods that is the one. You can take the specula off and use it like a mini lighted magnifying glass.
Brian
Quote from: Peter Drouin on March 25, 2014, 10:24:34 PM
Thanks 5quarter for agreeing with me on this . I won't go into how important it is for Coolant. :)
If you're using a sharpener with coolant, whether water or oil, you can make a heavier grind than with the Cat Claw without damaging your blade!
Which is why I mentioned take a light grind or you'll burn the blade if you're using the Cat Claw!
Quote from: YellowHammer on 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
YH,
I'll send you a ruby rock so you can try one out.
The type of grind rock that is best for you comes down to a matter of personal preference. This is especially true with the blue and ruby rocks as they are very similar. However, keep in mind that both of these rocks only require a light 'dressing up' as they wear. The tendency is to treat them as a harder rock which is counter to what a ceramic rock requires.
Remember that the objective is only to remove the dull grit; not to entirely re-shape the rock. This can usually be accomplished with a light tapping of the rock with a shaping stone rather than continuous contact which can result in excess grit removal.
Ultimately, any of the dry grind rocks can produce a sharp edge; how hard you grind, and how aggressive you are with shaping them are two major factors that will determine rock life.
James
Peter and Chuck...That's the nice thing about the CBN sharpener. It really takes the worry out of burning the tips of the teeth. I wonder why Cooks hasn't engineered a coolant option for the cats claw? you'd have the versatility of a drag type sharpener with the cooling ability of a full grind type sharpener.
Quote from: CooksSaw on March 26, 2014, 03:30:05 PM
YH,
I'll send you a ruby rock so you can try one out.
James
That is service! Thanks! I didn't even know you guys offered a ruby rock. I'm looking forward to trying it out.
I've been taking advantage of the advice and latest cold spell to "hone" my sharpening technique ::) and was able to buy one if the little optiscopes at a local drugstore yesterday. I also added some extra light and have a much better view of the corners of the teeth and can now better see the little glint indicating when its still just a little dull.
I appreciate all the advice on the subject, and have to explain that one of the reasons I'm trying to get my sharpening technique dialed in is that as a business, when I turn the mill on, I need to be cranking out the wood full steam and even with the limited sharpening and setting I've been doing I'm seeing a substantial increase in sawing speed and quality.
YH
Yes YH, get your sharpening down that is as important as selling the lumber.
Best of luck with your blades and selling wood. 8) 8) 8) 8) 8) 8) 8)
To me the difference between the blue and ruby ceramic wheels is the color. If sharpening is done right on the cats theirs no need for coolant. Coolant is used when you want to hog off a lot of material to speed up a sharpening process. Frank C.
Quote from: YellowHammer on March 26, 2014, 11:21:11 PM
That is service! Thanks! I didn't even know you guys offered a ruby rock. I'm looking forward to trying it out.
I've been taking advantage of the advice and latest cold spell to "hone" my sharpening technique ::) and was able to buy one if the little optiscopes at a local drugstore yesterday. I also added some extra light and have a much better view of the corners of the teeth and can now better see the little glint indicating when its still just a little dull.
I appreciate all the advice on the subject, and have to explain that one of the reasons I'm trying to get my sharpening technique dialed in is that as a business, when I turn the mill on, I need to be cranking out the wood full steam and even with the limited sharpening and setting I've been doing I'm seeing a substantial increase in sawing speed and quality.
YH
You should receive your rock by Friday.
One other small bit of advice as you're learning to sharpen (especially for others); sharpen until all the dull points (rounded sides) become keen (squared), then very lightly sharpen one more time. That last light grind puts a polished finish on the edge and will help that blade rip through some wood and have customers coming back for repeat business.
James
James, is there a best speed to set the feed to get the sharpest edge with the cats claw.?? Frank C.
I don't know if it's best or not, but I like to set my dial between 3 and 5 with a real light kiss on the blade.
Quote from: bandmiller2 on March 28, 2014, 07:05:32 AM
James, is there a best speed to set the feed to get the sharpest edge with the cats claw.?? Frank C.
Frank,
The best grind is almost always going to come from a slower grind as it hones the edge; the faster the grind the rougher the finish. Both are 'sharp' however the slower grind will produce a keener edge.
Having said that, we have found that sharpening a tooth every two seconds or 30 teeth per minute is a speed that will hone whereas moving up to 50,60 or higher produces a rougher finish. Both will produce sharp blades. Determining whether the performance difference between the two is worth the extra time it takes to sharpen will be up to you.
Hope that helps.
James
Very useful information. I received my ruby rock, and I'm going to experiment a little with both rocks, and feed speeds during the rain tomorrow and try to take some decent pictures of the results.
If I can't be sawing, I can be sharpening.
YH
Quote from: CooksSaw on March 28, 2014, 09:58:22 AM
Quote from: bandmiller2 on March 28, 2014, 07:05:32 AM
James, is there a best speed to set the feed to get the sharpest edge with the cats claw.?? Frank C.
Frank,
The best grind is almost always going to come from a slower grind as it hones the edge; the faster the grind the rougher the finish. Both are 'sharp' however the slower grind will produce a keener edge.
Having said that, we have found that sharpening a tooth every two seconds or 30 teeth per minute is a speed that will hone whereas moving up to 50,60 or higher produces a rougher finish. Both will produce sharp blades. Determining whether the performance difference between the two is worth the extra time it takes to sharpen will be up to you.
Hope that helps.
James
Just to add a note to James' post.
Good info indeed, but we all must remember that grinding s l o w we need to be less aggressive with our grind or we'll end up burning the band!
I've been using the advice from everybody to do a little sharpening between rainstorms and sawing jobs. Here are a few pictures I thought would be interesting. I took these viewing through my optiscope.
The first picture is of a tooth showing the glint of an unsharpened end corner of the tooth.
(https://forestryforum.com/gallery/albums/userpics/21488/image%7E42.jpg)
The second picture is of a tapered tooth, with a slightly tapered or rounded edge of tooth.
(https://forestryforum.com/gallery/albums/userpics/21488/image%7E43.jpg)
They finally, I got to this, a nice shaped chisel edge
(https://forestryforum.com/gallery/albums/userpics/21488/image%7E45.jpg)
YH
much better results! are those first 2 pics of teeth that have already been around the sharpener? are you using the new wheel James sent? how's it working out?
When you start looking at the fine details your results will greatly improve.
Your on it now YH 8)
Ayup, with any tooth or bit its the corners that are most important and dull first. Frank C.
Quote from: bandmiller2 on April 01, 2014, 08:13:32 AM
Ayup, with any tooth or bit its the corners that are most important and dull first. Frank C.
smiley_thumbsup
I need to get me one of them thar magnifiers ;)
Quote from: 5quarter on April 01, 2014, 01:18:04 AM
are those first 2 pics of teeth that have already been around the sharpener? are you using the new wheel James sent? how's it working out?
Yes the first 2 pics are of teeth that had already gone around.
The first picture was after the first pass, and if you look, it also shows a slightly burned tip.
The second photo was after the second pass, and the third photo was after the third pass.
I have been using the Ruby rock, and it does seem to have subtle differences, but I want to get a little more seat time with it before I say anything...but it certainly sharpens blades well, at least as well as the blue rocks.
The magnifiers work great, I think I paid 8 bucks at the local drugstore for,it.
YH
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 switch to a finer grit wheel if I saw marks like that on saw teeth.Try Norton wheels 32a and 36a.These numbers refer to wheel type.
(https://forestryforum.com/gallery/albums/userpics/21488/Tooth_Face.jpg)
After looking at the photos I wonder if the face of the tooth is exactly 90 degrees from the body of the saw.Hard to see on a thin blade.When I sharpen large rip circular blades I find a 5 degree bevel on the tooth face makes a saw cut faster and stay sharp longer..The scratches I see say that the wheels have too coarse a grit.Band saw teeth are induction hardened.Hard steel calls for soft grinding wheels and light grinding.I think you should do a light grind AFTER setting.Also only the tip of the tooth should be set.Setting the whole tooth make a saw run hard.Takes more pressure to hand feed a table saw.
Quote from: 36 coupe on April 03, 2014, 08:37:39 AM
After looking at the photos I wonder if the face of the tooth is exactly 90 degrees from the body of the saw.Hard to see on a thin blade.When I sharpen large rip circular blades I find a 5 degree bevel on the tooth face makes a saw cut faster and stay sharp longer..The scratches I see say that the wheels have too coarse a grit. Band saw teeth are induction hardened.Hard steel calls for soft grinding wheels and light grinding.I think you should do a light grind AFTER setting.Also only the tip of the tooth should be set.Setting the whole tooth make a saw run hard.Takes more pressure to hand feed a table saw.
The scratches going across the teeth are also caused by a
fast feed.
Slow the feed down a little, grind lightly and the scratches will decrease!